| Message ID | 20201206215554.350230-1-trix@redhat.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
| Series | [RFC] fpga: dfl: a prototype uio driver | expand |
On Sun, Dec 06, 2020 at 01:55:54PM -0800, trix@redhat.com wrote: > From: Tom Rix <trix@redhat.com> > > >From [PATCH 0/2] UIO support for dfl devices > https://lore.kernel.org/linux-fpga/1602828151-24784-1-git-send-email-yilun.xu@intel.com/ > > Here is an idea to have uio support with no driver override. > > This makes UIO the primary driver interface because every feature > will have one and makes the existing platform driver interface > secondary. There will be a new burden for locking write access when > they compete. > > Example shows finding the fpga's temperture. Hi Tom: Thanks for the idea and detailed illustrate with the patch. I see it abandons the driver_override and expose all the DFL devices to userspace by UIO. I'd like to see if we could get some more comments on it. Thanks, Yilun > > Signed-off-by: Tom Rix <trix@redhat.com> > --- > drivers/fpga/dfl-fme-main.c | 9 +++- > drivers/fpga/dfl-uio.c | 96 +++++++++++++++++++++++++++++++++++++ > drivers/fpga/dfl.c | 44 ++++++++++++++++- > drivers/fpga/dfl.h | 9 ++++ > uio.c | 56 ++++++++++++++++++++++ > 5 files changed, 212 insertions(+), 2 deletions(-) > create mode 100644 drivers/fpga/dfl-uio.c > create mode 100644 uio.c > > diff --git a/drivers/fpga/dfl-fme-main.c b/drivers/fpga/dfl-fme-main.c > index 037dc4f946f0..3323e90a18c4 100644 > --- a/drivers/fpga/dfl-fme-main.c > +++ b/drivers/fpga/dfl-fme-main.c > @@ -709,12 +709,18 @@ static int fme_probe(struct platform_device *pdev) > if (ret) > goto dev_destroy; > > - ret = dfl_fpga_dev_ops_register(pdev, &fme_fops, THIS_MODULE); > + ret = dfl_fpga_dev_feature_init_uio(pdev, DFH_TYPE_FIU); > if (ret) > goto feature_uinit; > > + ret = dfl_fpga_dev_ops_register(pdev, &fme_fops, THIS_MODULE); > + if (ret) > + goto feature_uinit_uio; > + > return 0; > > +feature_uinit_uio: > + dfl_fpga_dev_feature_uinit_uio(pdev, DFH_TYPE_FIU); > feature_uinit: > dfl_fpga_dev_feature_uinit(pdev); > dev_destroy: > @@ -726,6 +732,7 @@ exit: > static int fme_remove(struct platform_device *pdev) > { > dfl_fpga_dev_ops_unregister(pdev); > + dfl_fpga_dev_feature_uinit_uio(pdev, DFH_TYPE_FIU); > dfl_fpga_dev_feature_uinit(pdev); > fme_dev_destroy(pdev); > > diff --git a/drivers/fpga/dfl-uio.c b/drivers/fpga/dfl-uio.c > new file mode 100644 > index 000000000000..7610ee0b19dc > --- /dev/null > +++ b/drivers/fpga/dfl-uio.c > @@ -0,0 +1,96 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* > + * prototype dfl uio driver > + * > + * Copyright Tom Rix 2020 > + */ > +#include <linux/module.h> > +#include "dfl.h" > + > +static irqreturn_t dfl_uio_handler(int irq, struct uio_info *info) > +{ > + return IRQ_HANDLED; > +} > + > +static int dfl_uio_mmap(struct uio_info *info, struct vm_area_struct *vma) > +{ > + int ret = -ENODEV; > + return ret; > +} > + > +static int dfl_uio_open(struct uio_info *info, struct inode *inode) > +{ > + int ret = -ENODEV; > + struct dfl_feature *feature = container_of(info, struct dfl_feature, uio); > + if (feature->dev) > + mutex_lock(&feature->lock); > + > + ret = 0; > + return ret; > +} > + > +static int dfl_uio_release(struct uio_info *info, struct inode *inode) > +{ > + int ret = -ENODEV; > + struct dfl_feature *feature = container_of(info, struct dfl_feature, uio); > + if (feature->dev) > + mutex_unlock(&feature->lock); > + > + ret = 0; > + return ret; > +} > + > +static int dfl_uio_irqcontrol(struct uio_info *info, s32 irq_on) > +{ > + int ret = -ENODEV; > + return ret; > +} > + > +int dfl_uio_add(struct dfl_feature *feature) > +{ > + struct uio_info *uio = &feature->uio; > + struct resource *res = > + &feature->dev->resource[feature->resource_index]; > + int ret = 0; > + > + uio->name = kasprintf(GFP_KERNEL, "dfl-uio-%llx", feature->id); > + if (!uio->name) { > + ret = -ENOMEM; > + goto exit; > + } > + > + uio->version = "0.1"; > + uio->mem[0].memtype = UIO_MEM_PHYS; > + uio->mem[0].addr = res->start & PAGE_MASK; > + uio->mem[0].offs = res->start & ~PAGE_MASK; > + uio->mem[0].size = (uio->mem[0].offs + resource_size(res) > + + PAGE_SIZE - 1) & PAGE_MASK; > + /* How are nr_irqs > 1 handled ??? */ > + if (feature->nr_irqs == 1) > + uio->irq = feature->irq_ctx[0].irq; > + uio->handler = dfl_uio_handler; > + //uio->mmap = dfl_uio_mmap; > + uio->open = dfl_uio_open; > + uio->release = dfl_uio_release; > + uio->irqcontrol = dfl_uio_irqcontrol; > + > + ret = uio_register_device(&feature->dev->dev, uio); > + if (ret) > + goto err_register; > + > +exit: > + return ret; > +err_register: > + kfree(uio->name); > + goto exit; > +} > +EXPORT_SYMBOL_GPL(dfl_uio_add); > + > +int dfl_uio_remove(struct dfl_feature *feature) > +{ > + uio_unregister_device(&feature->uio); > + kfree(feature->uio.name); > + return 0; > +} > +EXPORT_SYMBOL_GPL(dfl_uio_remove); > + > diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c > index 1305be48037d..af2cd3d1b5f6 100644 > --- a/drivers/fpga/dfl.c > +++ b/drivers/fpga/dfl.c > @@ -603,6 +603,7 @@ static int dfl_feature_instance_init(struct platform_device *pdev, > } > > feature->ops = drv->ops; > + mutex_init(&feature->lock); > > return ret; > } > @@ -663,10 +664,51 @@ exit: > } > EXPORT_SYMBOL_GPL(dfl_fpga_dev_feature_init); > > +int dfl_fpga_dev_feature_init_uio(struct platform_device *pdev, int dfh_type) { > + struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev); > + struct dfl_feature *feature; > + int ret; > + > + dfl_fpga_dev_for_each_feature(pdata, feature) { > + if (dfh_type == DFH_TYPE_FIU) { > + if (feature->id == FEATURE_ID_FIU_HEADER || > + feature->id == FEATURE_ID_AFU) > + continue; > + > + ret = dfl_uio_add(feature); > + if (ret) > + goto exit; > + } > + } > + > + return 0; > +exit: > + dfl_fpga_dev_feature_uinit_uio(pdev, dfh_type); > + return ret; > +} > +EXPORT_SYMBOL_GPL(dfl_fpga_dev_feature_init_uio); > + > +int dfl_fpga_dev_feature_uinit_uio(struct platform_device *pdev, int dfh_type) { > + struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev); > + struct dfl_feature *feature; > + int ret = 0; > + > + dfl_fpga_dev_for_each_feature(pdata, feature) { > + if (dfh_type == DFH_TYPE_FIU) { > + if (feature->id == FEATURE_ID_FIU_HEADER || > + feature->id == FEATURE_ID_AFU) > + continue; > + > + ret |= dfl_uio_remove(feature); > + } > + } > + return ret; > +} > +EXPORT_SYMBOL_GPL(dfl_fpga_dev_feature_uinit_uio); > + > static void dfl_chardev_uinit(void) > { > int i; > - > for (i = 0; i < DFL_FPGA_DEVT_MAX; i++) > if (MAJOR(dfl_chrdevs[i].devt)) { > unregister_chrdev_region(dfl_chrdevs[i].devt, > diff --git a/drivers/fpga/dfl.h b/drivers/fpga/dfl.h > index a85d1cd7a130..fde0fc902d4d 100644 > --- a/drivers/fpga/dfl.h > +++ b/drivers/fpga/dfl.h > @@ -26,6 +26,7 @@ > #include <linux/platform_device.h> > #include <linux/slab.h> > #include <linux/uuid.h> > +#include <linux/uio_driver.h> > #include <linux/fpga/fpga-region.h> > > /* maximum supported number of ports */ > @@ -232,6 +233,7 @@ struct dfl_feature_irq_ctx { > * struct dfl_feature - sub feature of the feature devices > * > * @dev: ptr to pdev of the feature device which has the sub feature. > + * @uio: uio interface for feature. > * @id: sub feature id. > * @index: unique identifier for an sub feature within the feature device. > * It is possible that multiply sub features with same feature id are > @@ -248,6 +250,8 @@ struct dfl_feature_irq_ctx { > */ > struct dfl_feature { > struct platform_device *dev; > + struct uio_info uio; > + struct mutex lock; /* serialize dev and uio */ > u64 id; > int index; > int resource_index; > @@ -360,6 +364,11 @@ void dfl_fpga_dev_feature_uinit(struct platform_device *pdev); > int dfl_fpga_dev_feature_init(struct platform_device *pdev, > struct dfl_feature_driver *feature_drvs); > > +int dfl_fpga_dev_feature_init_uio(struct platform_device *pdev, int dfh_type); > +int dfl_fpga_dev_feature_uinit_uio(struct platform_device *pdev, int dfh_type); > +int dfl_uio_add(struct dfl_feature *feature); > +int dfl_uio_remove(struct dfl_feature *feature); > + > int dfl_fpga_dev_ops_register(struct platform_device *pdev, > const struct file_operations *fops, > struct module *owner); > diff --git a/uio.c b/uio.c > new file mode 100644 > index 000000000000..50210aab4822 > --- /dev/null > +++ b/uio.c > @@ -0,0 +1,56 @@ > +#include <stdlib.h> > +#include <stdio.h> > +#include <unistd.h> > +#include <sys/mman.h> > +#include <sys/types.h> > +#include <sys/stat.h> > +#include <fcntl.h> > +#include <errno.h> > +#include <stdint.h> > + > +int main() > +{ > + int fd; > + uint64_t *ptr; > + unsigned page_size=sysconf(_SC_PAGESIZE); > + struct stat sb; > + > + /* > + * this is fid 1, thermal mgt > + * ex/ > + * # cat /sys/class/hwmon/hwmon3/temp1_input > + * 39000 > + */ > + fd = open("/dev/uio0", O_RDONLY|O_SYNC); > + if (fd < 0) { > + perror("uio open:"); > + return errno; > + } > + > + ptr = (uint64_t *) mmap(NULL, page_size, PROT_READ, MAP_SHARED, fd, 0); > + if (!ptr) { > + perror("uio mmap:"); > + } else { > + > + /* from dfl-fme-main.c : > + * > + * #define FME_THERM_RDSENSOR_FMT1 0x10 > + * #define FPGA_TEMPERATURE GENMASK_ULL(6, 0) > + * > + * case hwmon_temp_input: > + * v = readq(feature->ioaddr + FME_THERM_RDSENSOR_FMT1); > + * *val = (long)(FIELD_GET(FPGA_TEMPERATURE, v) * 1000); > + * break; > + */ > + uint64_t v = ptr[2]; > + v &= (1 << 6) -1; > + v *= 1000; > + printf("Temperature %d\n", v); > + > + munmap(ptr, page_size); > + } > + if (close(fd)) > + perror("uio close:"); > + > + return errno; > +} > -- > 2.18.4
> Subject: Re: [RFC] fpga: dfl: a prototype uio driver > > On Sun, Dec 06, 2020 at 01:55:54PM -0800, trix@redhat.com wrote: > > From: Tom Rix <trix@redhat.com> > > > > >From [PATCH 0/2] UIO support for dfl devices > > https://lore.kernel.org/linux-fpga/1602828151-24784-1-git-send-email- > yilun.xu@intel.com/ > > > > Here is an idea to have uio support with no driver override. > > > > This makes UIO the primary driver interface because every feature > > will have one and makes the existing platform driver interface > > secondary. There will be a new burden for locking write access when > > they compete. > > > > Example shows finding the fpga's temperture. > > Hi Tom: > > Thanks for the idea and detailed illustrate with the patch. I see it > abandons the driver_override and expose all the DFL devices to userspace > by UIO. I'd like to see if we could get some more comments on it. This allows concurrent access from both userspace and kernel space driver to the same feature device? conflicts? Hao > > Thanks, > Yilun > > > > > Signed-off-by: Tom Rix <trix@redhat.com> > > --- > > drivers/fpga/dfl-fme-main.c | 9 +++- > > drivers/fpga/dfl-uio.c | 96 +++++++++++++++++++++++++++++++++++++ > > drivers/fpga/dfl.c | 44 ++++++++++++++++- > > drivers/fpga/dfl.h | 9 ++++ > > uio.c | 56 ++++++++++++++++++++++ > > 5 files changed, 212 insertions(+), 2 deletions(-) > > create mode 100644 drivers/fpga/dfl-uio.c > > create mode 100644 uio.c > > > > diff --git a/drivers/fpga/dfl-fme-main.c b/drivers/fpga/dfl-fme-main.c > > index 037dc4f946f0..3323e90a18c4 100644 > > --- a/drivers/fpga/dfl-fme-main.c > > +++ b/drivers/fpga/dfl-fme-main.c > > @@ -709,12 +709,18 @@ static int fme_probe(struct platform_device > *pdev) > > if (ret) > > goto dev_destroy; > > > > - ret = dfl_fpga_dev_ops_register(pdev, &fme_fops, THIS_MODULE); > > + ret = dfl_fpga_dev_feature_init_uio(pdev, DFH_TYPE_FIU); > > if (ret) > > goto feature_uinit; > > > > + ret = dfl_fpga_dev_ops_register(pdev, &fme_fops, THIS_MODULE); > > + if (ret) > > + goto feature_uinit_uio; > > + > > return 0; > > > > +feature_uinit_uio: > > + dfl_fpga_dev_feature_uinit_uio(pdev, DFH_TYPE_FIU); > > feature_uinit: > > dfl_fpga_dev_feature_uinit(pdev); > > dev_destroy: > > @@ -726,6 +732,7 @@ exit: > > static int fme_remove(struct platform_device *pdev) > > { > > dfl_fpga_dev_ops_unregister(pdev); > > + dfl_fpga_dev_feature_uinit_uio(pdev, DFH_TYPE_FIU); > > dfl_fpga_dev_feature_uinit(pdev); > > fme_dev_destroy(pdev); > > > > diff --git a/drivers/fpga/dfl-uio.c b/drivers/fpga/dfl-uio.c > > new file mode 100644 > > index 000000000000..7610ee0b19dc > > --- /dev/null > > +++ b/drivers/fpga/dfl-uio.c > > @@ -0,0 +1,96 @@ > > +/* SPDX-License-Identifier: GPL-2.0 */ > > +/* > > + * prototype dfl uio driver > > + * > > + * Copyright Tom Rix 2020 > > + */ > > +#include <linux/module.h> > > +#include "dfl.h" > > + > > +static irqreturn_t dfl_uio_handler(int irq, struct uio_info *info) > > +{ > > + return IRQ_HANDLED; > > +} > > + > > +static int dfl_uio_mmap(struct uio_info *info, struct vm_area_struct *vma) > > +{ > > + int ret = -ENODEV; > > + return ret; > > +} > > + > > +static int dfl_uio_open(struct uio_info *info, struct inode *inode) > > +{ > > + int ret = -ENODEV; > > + struct dfl_feature *feature = container_of(info, struct dfl_feature, > uio); > > + if (feature->dev) > > + mutex_lock(&feature->lock); > > + > > + ret = 0; > > + return ret; > > +} > > + > > +static int dfl_uio_release(struct uio_info *info, struct inode *inode) > > +{ > > + int ret = -ENODEV; > > + struct dfl_feature *feature = container_of(info, struct dfl_feature, > uio); > > + if (feature->dev) > > + mutex_unlock(&feature->lock); > > + > > + ret = 0; > > + return ret; > > +} > > + > > +static int dfl_uio_irqcontrol(struct uio_info *info, s32 irq_on) > > +{ > > + int ret = -ENODEV; > > + return ret; > > +} > > + > > +int dfl_uio_add(struct dfl_feature *feature) > > +{ > > + struct uio_info *uio = &feature->uio; > > + struct resource *res = > > + &feature->dev->resource[feature->resource_index]; > > + int ret = 0; > > + > > + uio->name = kasprintf(GFP_KERNEL, "dfl-uio-%llx", feature->id); > > + if (!uio->name) { > > + ret = -ENOMEM; > > + goto exit; > > + } > > + > > + uio->version = "0.1"; > > + uio->mem[0].memtype = UIO_MEM_PHYS; > > + uio->mem[0].addr = res->start & PAGE_MASK; > > + uio->mem[0].offs = res->start & ~PAGE_MASK; > > + uio->mem[0].size = (uio->mem[0].offs + resource_size(res) > > + + PAGE_SIZE - 1) & PAGE_MASK; > > + /* How are nr_irqs > 1 handled ??? */ > > + if (feature->nr_irqs == 1) > > + uio->irq = feature->irq_ctx[0].irq; > > + uio->handler = dfl_uio_handler; > > + //uio->mmap = dfl_uio_mmap; > > + uio->open = dfl_uio_open; > > + uio->release = dfl_uio_release; > > + uio->irqcontrol = dfl_uio_irqcontrol; > > + > > + ret = uio_register_device(&feature->dev->dev, uio); > > + if (ret) > > + goto err_register; > > + > > +exit: > > + return ret; > > +err_register: > > + kfree(uio->name); > > + goto exit; > > +} > > +EXPORT_SYMBOL_GPL(dfl_uio_add); > > + > > +int dfl_uio_remove(struct dfl_feature *feature) > > +{ > > + uio_unregister_device(&feature->uio); > > + kfree(feature->uio.name); > > + return 0; > > +} > > +EXPORT_SYMBOL_GPL(dfl_uio_remove); > > + > > diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c > > index 1305be48037d..af2cd3d1b5f6 100644 > > --- a/drivers/fpga/dfl.c > > +++ b/drivers/fpga/dfl.c > > @@ -603,6 +603,7 @@ static int dfl_feature_instance_init(struct > platform_device *pdev, > > } > > > > feature->ops = drv->ops; > > + mutex_init(&feature->lock); > > > > return ret; > > } > > @@ -663,10 +664,51 @@ exit: > > } > > EXPORT_SYMBOL_GPL(dfl_fpga_dev_feature_init); > > > > +int dfl_fpga_dev_feature_init_uio(struct platform_device *pdev, int > dfh_type) { > > + struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev- > >dev); > > + struct dfl_feature *feature; > > + int ret; > > + > > + dfl_fpga_dev_for_each_feature(pdata, feature) { > > + if (dfh_type == DFH_TYPE_FIU) { > > + if (feature->id == FEATURE_ID_FIU_HEADER || > > + feature->id == FEATURE_ID_AFU) > > + continue; > > + > > + ret = dfl_uio_add(feature); > > + if (ret) > > + goto exit; > > + } > > + } > > + > > + return 0; > > +exit: > > + dfl_fpga_dev_feature_uinit_uio(pdev, dfh_type); > > + return ret; > > +} > > +EXPORT_SYMBOL_GPL(dfl_fpga_dev_feature_init_uio); > > + > > +int dfl_fpga_dev_feature_uinit_uio(struct platform_device *pdev, int > dfh_type) { > > + struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev- > >dev); > > + struct dfl_feature *feature; > > + int ret = 0; > > + > > + dfl_fpga_dev_for_each_feature(pdata, feature) { > > + if (dfh_type == DFH_TYPE_FIU) { > > + if (feature->id == FEATURE_ID_FIU_HEADER || > > + feature->id == FEATURE_ID_AFU) > > + continue; > > + > > + ret |= dfl_uio_remove(feature); > > + } > > + } > > + return ret; > > +} > > +EXPORT_SYMBOL_GPL(dfl_fpga_dev_feature_uinit_uio); > > + > > static void dfl_chardev_uinit(void) > > { > > int i; > > - > > for (i = 0; i < DFL_FPGA_DEVT_MAX; i++) > > if (MAJOR(dfl_chrdevs[i].devt)) { > > unregister_chrdev_region(dfl_chrdevs[i].devt, > > diff --git a/drivers/fpga/dfl.h b/drivers/fpga/dfl.h > > index a85d1cd7a130..fde0fc902d4d 100644 > > --- a/drivers/fpga/dfl.h > > +++ b/drivers/fpga/dfl.h > > @@ -26,6 +26,7 @@ > > #include <linux/platform_device.h> > > #include <linux/slab.h> > > #include <linux/uuid.h> > > +#include <linux/uio_driver.h> > > #include <linux/fpga/fpga-region.h> > > > > /* maximum supported number of ports */ > > @@ -232,6 +233,7 @@ struct dfl_feature_irq_ctx { > > * struct dfl_feature - sub feature of the feature devices > > * > > * @dev: ptr to pdev of the feature device which has the sub feature. > > + * @uio: uio interface for feature. > > * @id: sub feature id. > > * @index: unique identifier for an sub feature within the feature device. > > * It is possible that multiply sub features with same feature id are > > @@ -248,6 +250,8 @@ struct dfl_feature_irq_ctx { > > */ > > struct dfl_feature { > > struct platform_device *dev; > > + struct uio_info uio; > > + struct mutex lock; /* serialize dev and uio */ > > u64 id; > > int index; > > int resource_index; > > @@ -360,6 +364,11 @@ void dfl_fpga_dev_feature_uinit(struct > platform_device *pdev); > > int dfl_fpga_dev_feature_init(struct platform_device *pdev, > > struct dfl_feature_driver *feature_drvs); > > > > +int dfl_fpga_dev_feature_init_uio(struct platform_device *pdev, int > dfh_type); > > +int dfl_fpga_dev_feature_uinit_uio(struct platform_device *pdev, int > dfh_type); > > +int dfl_uio_add(struct dfl_feature *feature); > > +int dfl_uio_remove(struct dfl_feature *feature); > > + > > int dfl_fpga_dev_ops_register(struct platform_device *pdev, > > const struct file_operations *fops, > > struct module *owner); > > diff --git a/uio.c b/uio.c > > new file mode 100644 > > index 000000000000..50210aab4822 > > --- /dev/null > > +++ b/uio.c > > @@ -0,0 +1,56 @@ > > +#include <stdlib.h> > > +#include <stdio.h> > > +#include <unistd.h> > > +#include <sys/mman.h> > > +#include <sys/types.h> > > +#include <sys/stat.h> > > +#include <fcntl.h> > > +#include <errno.h> > > +#include <stdint.h> > > + > > +int main() > > +{ > > + int fd; > > + uint64_t *ptr; > > + unsigned page_size=sysconf(_SC_PAGESIZE); > > + struct stat sb; > > + > > + /* > > + * this is fid 1, thermal mgt > > + * ex/ > > + * # cat /sys/class/hwmon/hwmon3/temp1_input > > + * 39000 > > + */ > > + fd = open("/dev/uio0", O_RDONLY|O_SYNC); > > + if (fd < 0) { > > + perror("uio open:"); > > + return errno; > > + } > > + > > + ptr = (uint64_t *) mmap(NULL, page_size, PROT_READ, MAP_SHARED, > fd, 0); > > + if (!ptr) { > > + perror("uio mmap:"); > > + } else { > > + > > + /* from dfl-fme-main.c : > > + * > > + * #define FME_THERM_RDSENSOR_FMT1 0x10 > > + * #define FPGA_TEMPERATURE GENMASK_ULL(6, 0) > > + * > > + * case hwmon_temp_input: > > + * v = readq(feature->ioaddr + > FME_THERM_RDSENSOR_FMT1); > > + * *val = (long)(FIELD_GET(FPGA_TEMPERATURE, v) * 1000); > > + * break; > > + */ > > + uint64_t v = ptr[2]; > > + v &= (1 << 6) -1; > > + v *= 1000; > > + printf("Temperature %d\n", v); > > + > > + munmap(ptr, page_size); > > + } > > + if (close(fd)) > > + perror("uio close:"); > > + > > + return errno; > > +} > > -- > > 2.18.4
On Sun, Dec 06, 2020 at 01:55:54PM -0800, trix@redhat.com wrote: > From: Tom Rix <trix@redhat.com> > > >From [PATCH 0/2] UIO support for dfl devices > https://lore.kernel.org/linux-fpga/1602828151-24784-1-git-send-email-yilun.xu@intel.com/ Why is this here? > > Here is an idea to have uio support with no driver override. > > This makes UIO the primary driver interface because every feature > will have one and makes the existing platform driver interface > secondary. There will be a new burden for locking write access when > they compete. > > Example shows finding the fpga's temperture. > > Signed-off-by: Tom Rix <trix@redhat.com> > --- > drivers/fpga/dfl-fme-main.c | 9 +++- > drivers/fpga/dfl-uio.c | 96 +++++++++++++++++++++++++++++++++++++ > drivers/fpga/dfl.c | 44 ++++++++++++++++- > drivers/fpga/dfl.h | 9 ++++ > uio.c | 56 ++++++++++++++++++++++ > 5 files changed, 212 insertions(+), 2 deletions(-) > create mode 100644 drivers/fpga/dfl-uio.c > create mode 100644 uio.c > > diff --git a/drivers/fpga/dfl-fme-main.c b/drivers/fpga/dfl-fme-main.c > index 037dc4f946f0..3323e90a18c4 100644 > --- a/drivers/fpga/dfl-fme-main.c > +++ b/drivers/fpga/dfl-fme-main.c > @@ -709,12 +709,18 @@ static int fme_probe(struct platform_device *pdev) > if (ret) > goto dev_destroy; > > - ret = dfl_fpga_dev_ops_register(pdev, &fme_fops, THIS_MODULE); > + ret = dfl_fpga_dev_feature_init_uio(pdev, DFH_TYPE_FIU); > if (ret) > goto feature_uinit; > > + ret = dfl_fpga_dev_ops_register(pdev, &fme_fops, THIS_MODULE); > + if (ret) > + goto feature_uinit_uio; > + > return 0; > > +feature_uinit_uio: > + dfl_fpga_dev_feature_uinit_uio(pdev, DFH_TYPE_FIU); > feature_uinit: > dfl_fpga_dev_feature_uinit(pdev); > dev_destroy: > @@ -726,6 +732,7 @@ exit: > static int fme_remove(struct platform_device *pdev) > { > dfl_fpga_dev_ops_unregister(pdev); > + dfl_fpga_dev_feature_uinit_uio(pdev, DFH_TYPE_FIU); > dfl_fpga_dev_feature_uinit(pdev); > fme_dev_destroy(pdev); > > diff --git a/drivers/fpga/dfl-uio.c b/drivers/fpga/dfl-uio.c > new file mode 100644 > index 000000000000..7610ee0b19dc > --- /dev/null > +++ b/drivers/fpga/dfl-uio.c > @@ -0,0 +1,96 @@ > +/* SPDX-License-Identifier: GPL-2.0 */ > +/* > + * prototype dfl uio driver > + * > + * Copyright Tom Rix 2020 > + */ > +#include <linux/module.h> > +#include "dfl.h" > + > +static irqreturn_t dfl_uio_handler(int irq, struct uio_info *info) > +{ > + return IRQ_HANDLED; > +} > + > +static int dfl_uio_mmap(struct uio_info *info, struct vm_area_struct *vma) > +{ > + int ret = -ENODEV; > + return ret; Did you run this through checkpatch? Does the code make sense? > +} > + > +static int dfl_uio_open(struct uio_info *info, struct inode *inode) > +{ > + int ret = -ENODEV; > + struct dfl_feature *feature = container_of(info, struct dfl_feature, uio); > + if (feature->dev) > + mutex_lock(&feature->lock); > + > + ret = 0; > + return ret; Same here, does this make sense? And wait, you are having userspace grab a kernel lock? What could go wrong? :( > +} > + > +static int dfl_uio_release(struct uio_info *info, struct inode *inode) > +{ > + int ret = -ENODEV; > + struct dfl_feature *feature = container_of(info, struct dfl_feature, uio); > + if (feature->dev) > + mutex_unlock(&feature->lock); > + > + ret = 0; > + return ret; > +} > + > +static int dfl_uio_irqcontrol(struct uio_info *info, s32 irq_on) > +{ > + int ret = -ENODEV; > + return ret; > +} > + > +int dfl_uio_add(struct dfl_feature *feature) > +{ > + struct uio_info *uio = &feature->uio; > + struct resource *res = > + &feature->dev->resource[feature->resource_index]; > + int ret = 0; > + > + uio->name = kasprintf(GFP_KERNEL, "dfl-uio-%llx", feature->id); > + if (!uio->name) { > + ret = -ENOMEM; > + goto exit; > + } > + > + uio->version = "0.1"; > + uio->mem[0].memtype = UIO_MEM_PHYS; > + uio->mem[0].addr = res->start & PAGE_MASK; > + uio->mem[0].offs = res->start & ~PAGE_MASK; > + uio->mem[0].size = (uio->mem[0].offs + resource_size(res) > + + PAGE_SIZE - 1) & PAGE_MASK; > + /* How are nr_irqs > 1 handled ??? */ > + if (feature->nr_irqs == 1) > + uio->irq = feature->irq_ctx[0].irq; > + uio->handler = dfl_uio_handler; > + //uio->mmap = dfl_uio_mmap; ??? I don't understand what this patch is trying to show... thanks, greg k-h
On 12/6/20 10:24 PM, Wu, Hao wrote: >> Subject: Re: [RFC] fpga: dfl: a prototype uio driver >> >> On Sun, Dec 06, 2020 at 01:55:54PM -0800, trix@redhat.com wrote: >>> From: Tom Rix <trix@redhat.com> >>> >>> >From [PATCH 0/2] UIO support for dfl devices >>> https://lore.kernel.org/linux-fpga/1602828151-24784-1-git-send-email- >> yilun.xu@intel.com/ >>> Here is an idea to have uio support with no driver override. >>> >>> This makes UIO the primary driver interface because every feature >>> will have one and makes the existing platform driver interface >>> secondary. There will be a new burden for locking write access when >>> they compete. >>> >>> Example shows finding the fpga's temperture. >> Hi Tom: >> >> Thanks for the idea and detailed illustrate with the patch. I see it >> abandons the driver_override and expose all the DFL devices to userspace >> by UIO. I'd like to see if we could get some more comments on it. > This allows concurrent access from both userspace and kernel space driver > to the same feature device? conflicts? Yes conflicts, that is why a lock is needed and the unpleasant part of this idea. Another way is split them and have uio for the unclaimed feature id's Tom > > Hao > >> Thanks, >> Yilun >> >>> Signed-off-by: Tom Rix <trix@redhat.com> >>> --- >>> drivers/fpga/dfl-fme-main.c | 9 +++- >>> drivers/fpga/dfl-uio.c | 96 +++++++++++++++++++++++++++++++++++++ >>> drivers/fpga/dfl.c | 44 ++++++++++++++++- >>> drivers/fpga/dfl.h | 9 ++++ >>> uio.c | 56 ++++++++++++++++++++++ >>> 5 files changed, 212 insertions(+), 2 deletions(-) >>> create mode 100644 drivers/fpga/dfl-uio.c >>> create mode 100644 uio.c >>> >>> diff --git a/drivers/fpga/dfl-fme-main.c b/drivers/fpga/dfl-fme-main.c >>> index 037dc4f946f0..3323e90a18c4 100644 >>> --- a/drivers/fpga/dfl-fme-main.c >>> +++ b/drivers/fpga/dfl-fme-main.c >>> @@ -709,12 +709,18 @@ static int fme_probe(struct platform_device >> *pdev) >>> if (ret) >>> goto dev_destroy; >>> >>> - ret = dfl_fpga_dev_ops_register(pdev, &fme_fops, THIS_MODULE); >>> + ret = dfl_fpga_dev_feature_init_uio(pdev, DFH_TYPE_FIU); >>> if (ret) >>> goto feature_uinit; >>> >>> + ret = dfl_fpga_dev_ops_register(pdev, &fme_fops, THIS_MODULE); >>> + if (ret) >>> + goto feature_uinit_uio; >>> + >>> return 0; >>> >>> +feature_uinit_uio: >>> + dfl_fpga_dev_feature_uinit_uio(pdev, DFH_TYPE_FIU); >>> feature_uinit: >>> dfl_fpga_dev_feature_uinit(pdev); >>> dev_destroy: >>> @@ -726,6 +732,7 @@ exit: >>> static int fme_remove(struct platform_device *pdev) >>> { >>> dfl_fpga_dev_ops_unregister(pdev); >>> + dfl_fpga_dev_feature_uinit_uio(pdev, DFH_TYPE_FIU); >>> dfl_fpga_dev_feature_uinit(pdev); >>> fme_dev_destroy(pdev); >>> >>> diff --git a/drivers/fpga/dfl-uio.c b/drivers/fpga/dfl-uio.c >>> new file mode 100644 >>> index 000000000000..7610ee0b19dc >>> --- /dev/null >>> +++ b/drivers/fpga/dfl-uio.c >>> @@ -0,0 +1,96 @@ >>> +/* SPDX-License-Identifier: GPL-2.0 */ >>> +/* >>> + * prototype dfl uio driver >>> + * >>> + * Copyright Tom Rix 2020 >>> + */ >>> +#include <linux/module.h> >>> +#include "dfl.h" >>> + >>> +static irqreturn_t dfl_uio_handler(int irq, struct uio_info *info) >>> +{ >>> + return IRQ_HANDLED; >>> +} >>> + >>> +static int dfl_uio_mmap(struct uio_info *info, struct vm_area_struct *vma) >>> +{ >>> + int ret = -ENODEV; >>> + return ret; >>> +} >>> + >>> +static int dfl_uio_open(struct uio_info *info, struct inode *inode) >>> +{ >>> + int ret = -ENODEV; >>> + struct dfl_feature *feature = container_of(info, struct dfl_feature, >> uio); >>> + if (feature->dev) >>> + mutex_lock(&feature->lock); >>> + >>> + ret = 0; >>> + return ret; >>> +} >>> + >>> +static int dfl_uio_release(struct uio_info *info, struct inode *inode) >>> +{ >>> + int ret = -ENODEV; >>> + struct dfl_feature *feature = container_of(info, struct dfl_feature, >> uio); >>> + if (feature->dev) >>> + mutex_unlock(&feature->lock); >>> + >>> + ret = 0; >>> + return ret; >>> +} >>> + >>> +static int dfl_uio_irqcontrol(struct uio_info *info, s32 irq_on) >>> +{ >>> + int ret = -ENODEV; >>> + return ret; >>> +} >>> + >>> +int dfl_uio_add(struct dfl_feature *feature) >>> +{ >>> + struct uio_info *uio = &feature->uio; >>> + struct resource *res = >>> + &feature->dev->resource[feature->resource_index]; >>> + int ret = 0; >>> + >>> + uio->name = kasprintf(GFP_KERNEL, "dfl-uio-%llx", feature->id); >>> + if (!uio->name) { >>> + ret = -ENOMEM; >>> + goto exit; >>> + } >>> + >>> + uio->version = "0.1"; >>> + uio->mem[0].memtype = UIO_MEM_PHYS; >>> + uio->mem[0].addr = res->start & PAGE_MASK; >>> + uio->mem[0].offs = res->start & ~PAGE_MASK; >>> + uio->mem[0].size = (uio->mem[0].offs + resource_size(res) >>> + + PAGE_SIZE - 1) & PAGE_MASK; >>> + /* How are nr_irqs > 1 handled ??? */ >>> + if (feature->nr_irqs == 1) >>> + uio->irq = feature->irq_ctx[0].irq; >>> + uio->handler = dfl_uio_handler; >>> + //uio->mmap = dfl_uio_mmap; >>> + uio->open = dfl_uio_open; >>> + uio->release = dfl_uio_release; >>> + uio->irqcontrol = dfl_uio_irqcontrol; >>> + >>> + ret = uio_register_device(&feature->dev->dev, uio); >>> + if (ret) >>> + goto err_register; >>> + >>> +exit: >>> + return ret; >>> +err_register: >>> + kfree(uio->name); >>> + goto exit; >>> +} >>> +EXPORT_SYMBOL_GPL(dfl_uio_add); >>> + >>> +int dfl_uio_remove(struct dfl_feature *feature) >>> +{ >>> + uio_unregister_device(&feature->uio); >>> + kfree(feature->uio.name); >>> + return 0; >>> +} >>> +EXPORT_SYMBOL_GPL(dfl_uio_remove); >>> + >>> diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c >>> index 1305be48037d..af2cd3d1b5f6 100644 >>> --- a/drivers/fpga/dfl.c >>> +++ b/drivers/fpga/dfl.c >>> @@ -603,6 +603,7 @@ static int dfl_feature_instance_init(struct >> platform_device *pdev, >>> } >>> >>> feature->ops = drv->ops; >>> + mutex_init(&feature->lock); >>> >>> return ret; >>> } >>> @@ -663,10 +664,51 @@ exit: >>> } >>> EXPORT_SYMBOL_GPL(dfl_fpga_dev_feature_init); >>> >>> +int dfl_fpga_dev_feature_init_uio(struct platform_device *pdev, int >> dfh_type) { >>> + struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev- >>> dev); >>> + struct dfl_feature *feature; >>> + int ret; >>> + >>> + dfl_fpga_dev_for_each_feature(pdata, feature) { >>> + if (dfh_type == DFH_TYPE_FIU) { >>> + if (feature->id == FEATURE_ID_FIU_HEADER || >>> + feature->id == FEATURE_ID_AFU) >>> + continue; >>> + >>> + ret = dfl_uio_add(feature); >>> + if (ret) >>> + goto exit; >>> + } >>> + } >>> + >>> + return 0; >>> +exit: >>> + dfl_fpga_dev_feature_uinit_uio(pdev, dfh_type); >>> + return ret; >>> +} >>> +EXPORT_SYMBOL_GPL(dfl_fpga_dev_feature_init_uio); >>> + >>> +int dfl_fpga_dev_feature_uinit_uio(struct platform_device *pdev, int >> dfh_type) { >>> + struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev- >>> dev); >>> + struct dfl_feature *feature; >>> + int ret = 0; >>> + >>> + dfl_fpga_dev_for_each_feature(pdata, feature) { >>> + if (dfh_type == DFH_TYPE_FIU) { >>> + if (feature->id == FEATURE_ID_FIU_HEADER || >>> + feature->id == FEATURE_ID_AFU) >>> + continue; >>> + >>> + ret |= dfl_uio_remove(feature); >>> + } >>> + } >>> + return ret; >>> +} >>> +EXPORT_SYMBOL_GPL(dfl_fpga_dev_feature_uinit_uio); >>> + >>> static void dfl_chardev_uinit(void) >>> { >>> int i; >>> - >>> for (i = 0; i < DFL_FPGA_DEVT_MAX; i++) >>> if (MAJOR(dfl_chrdevs[i].devt)) { >>> unregister_chrdev_region(dfl_chrdevs[i].devt, >>> diff --git a/drivers/fpga/dfl.h b/drivers/fpga/dfl.h >>> index a85d1cd7a130..fde0fc902d4d 100644 >>> --- a/drivers/fpga/dfl.h >>> +++ b/drivers/fpga/dfl.h >>> @@ -26,6 +26,7 @@ >>> #include <linux/platform_device.h> >>> #include <linux/slab.h> >>> #include <linux/uuid.h> >>> +#include <linux/uio_driver.h> >>> #include <linux/fpga/fpga-region.h> >>> >>> /* maximum supported number of ports */ >>> @@ -232,6 +233,7 @@ struct dfl_feature_irq_ctx { >>> * struct dfl_feature - sub feature of the feature devices >>> * >>> * @dev: ptr to pdev of the feature device which has the sub feature. >>> + * @uio: uio interface for feature. >>> * @id: sub feature id. >>> * @index: unique identifier for an sub feature within the feature device. >>> * It is possible that multiply sub features with same feature id are >>> @@ -248,6 +250,8 @@ struct dfl_feature_irq_ctx { >>> */ >>> struct dfl_feature { >>> struct platform_device *dev; >>> + struct uio_info uio; >>> + struct mutex lock; /* serialize dev and uio */ >>> u64 id; >>> int index; >>> int resource_index; >>> @@ -360,6 +364,11 @@ void dfl_fpga_dev_feature_uinit(struct >> platform_device *pdev); >>> int dfl_fpga_dev_feature_init(struct platform_device *pdev, >>> struct dfl_feature_driver *feature_drvs); >>> >>> +int dfl_fpga_dev_feature_init_uio(struct platform_device *pdev, int >> dfh_type); >>> +int dfl_fpga_dev_feature_uinit_uio(struct platform_device *pdev, int >> dfh_type); >>> +int dfl_uio_add(struct dfl_feature *feature); >>> +int dfl_uio_remove(struct dfl_feature *feature); >>> + >>> int dfl_fpga_dev_ops_register(struct platform_device *pdev, >>> const struct file_operations *fops, >>> struct module *owner); >>> diff --git a/uio.c b/uio.c >>> new file mode 100644 >>> index 000000000000..50210aab4822 >>> --- /dev/null >>> +++ b/uio.c >>> @@ -0,0 +1,56 @@ >>> +#include <stdlib.h> >>> +#include <stdio.h> >>> +#include <unistd.h> >>> +#include <sys/mman.h> >>> +#include <sys/types.h> >>> +#include <sys/stat.h> >>> +#include <fcntl.h> >>> +#include <errno.h> >>> +#include <stdint.h> >>> + >>> +int main() >>> +{ >>> + int fd; >>> + uint64_t *ptr; >>> + unsigned page_size=sysconf(_SC_PAGESIZE); >>> + struct stat sb; >>> + >>> + /* >>> + * this is fid 1, thermal mgt >>> + * ex/ >>> + * # cat /sys/class/hwmon/hwmon3/temp1_input >>> + * 39000 >>> + */ >>> + fd = open("/dev/uio0", O_RDONLY|O_SYNC); >>> + if (fd < 0) { >>> + perror("uio open:"); >>> + return errno; >>> + } >>> + >>> + ptr = (uint64_t *) mmap(NULL, page_size, PROT_READ, MAP_SHARED, >> fd, 0); >>> + if (!ptr) { >>> + perror("uio mmap:"); >>> + } else { >>> + >>> + /* from dfl-fme-main.c : >>> + * >>> + * #define FME_THERM_RDSENSOR_FMT1 0x10 >>> + * #define FPGA_TEMPERATURE GENMASK_ULL(6, 0) >>> + * >>> + * case hwmon_temp_input: >>> + * v = readq(feature->ioaddr + >> FME_THERM_RDSENSOR_FMT1); >>> + * *val = (long)(FIELD_GET(FPGA_TEMPERATURE, v) * 1000); >>> + * break; >>> + */ >>> + uint64_t v = ptr[2]; >>> + v &= (1 << 6) -1; >>> + v *= 1000; >>> + printf("Temperature %d\n", v); >>> + >>> + munmap(ptr, page_size); >>> + } >>> + if (close(fd)) >>> + perror("uio close:"); >>> + >>> + return errno; >>> +} >>> -- >>> 2.18.4
On 12/7/20 12:02 AM, Greg KH wrote: > On Sun, Dec 06, 2020 at 01:55:54PM -0800, trix@redhat.com wrote: >> From: Tom Rix <trix@redhat.com> >> >> >From [PATCH 0/2] UIO support for dfl devices >> https://lore.kernel.org/linux-fpga/1602828151-24784-1-git-send-email-yilun.xu@intel.com/ > Why is this here? As reference, Yilun's work has precedence for a uio driver and this rfc is trying to address what i believe is a sticking point of the driver override. This rfc is some code i hacked out to show the idea and move uio support along. I would like to see uio support for at least the unclaimed feature id's because this would make it easier for them to be developed. >> Here is an idea to have uio support with no driver override. >> >> This makes UIO the primary driver interface because every feature >> will have one and makes the existing platform driver interface >> secondary. There will be a new burden for locking write access when >> they compete. >> >> Example shows finding the fpga's temperture. >> >> Signed-off-by: Tom Rix <trix@redhat.com> >> --- >> drivers/fpga/dfl-fme-main.c | 9 +++- >> drivers/fpga/dfl-uio.c | 96 +++++++++++++++++++++++++++++++++++++ >> drivers/fpga/dfl.c | 44 ++++++++++++++++- >> drivers/fpga/dfl.h | 9 ++++ >> uio.c | 56 ++++++++++++++++++++++ >> 5 files changed, 212 insertions(+), 2 deletions(-) >> create mode 100644 drivers/fpga/dfl-uio.c >> create mode 100644 uio.c >> >> diff --git a/drivers/fpga/dfl-fme-main.c b/drivers/fpga/dfl-fme-main.c >> index 037dc4f946f0..3323e90a18c4 100644 >> --- a/drivers/fpga/dfl-fme-main.c >> +++ b/drivers/fpga/dfl-fme-main.c >> @@ -709,12 +709,18 @@ static int fme_probe(struct platform_device *pdev) >> if (ret) >> goto dev_destroy; >> >> - ret = dfl_fpga_dev_ops_register(pdev, &fme_fops, THIS_MODULE); >> + ret = dfl_fpga_dev_feature_init_uio(pdev, DFH_TYPE_FIU); >> if (ret) >> goto feature_uinit; >> >> + ret = dfl_fpga_dev_ops_register(pdev, &fme_fops, THIS_MODULE); >> + if (ret) >> + goto feature_uinit_uio; >> + >> return 0; >> >> +feature_uinit_uio: >> + dfl_fpga_dev_feature_uinit_uio(pdev, DFH_TYPE_FIU); >> feature_uinit: >> dfl_fpga_dev_feature_uinit(pdev); >> dev_destroy: >> @@ -726,6 +732,7 @@ exit: >> static int fme_remove(struct platform_device *pdev) >> { >> dfl_fpga_dev_ops_unregister(pdev); >> + dfl_fpga_dev_feature_uinit_uio(pdev, DFH_TYPE_FIU); >> dfl_fpga_dev_feature_uinit(pdev); >> fme_dev_destroy(pdev); >> >> diff --git a/drivers/fpga/dfl-uio.c b/drivers/fpga/dfl-uio.c >> new file mode 100644 >> index 000000000000..7610ee0b19dc >> --- /dev/null >> +++ b/drivers/fpga/dfl-uio.c >> @@ -0,0 +1,96 @@ >> +/* SPDX-License-Identifier: GPL-2.0 */ >> +/* >> + * prototype dfl uio driver >> + * >> + * Copyright Tom Rix 2020 >> + */ >> +#include <linux/module.h> >> +#include "dfl.h" >> + >> +static irqreturn_t dfl_uio_handler(int irq, struct uio_info *info) >> +{ >> + return IRQ_HANDLED; >> +} >> + >> +static int dfl_uio_mmap(struct uio_info *info, struct vm_area_struct *vma) >> +{ >> + int ret = -ENODEV; >> + return ret; > Did you run this through checkpatch? > > Does the code make sense? > >> +} >> + >> +static int dfl_uio_open(struct uio_info *info, struct inode *inode) >> +{ >> + int ret = -ENODEV; >> + struct dfl_feature *feature = container_of(info, struct dfl_feature, uio); >> + if (feature->dev) >> + mutex_lock(&feature->lock); >> + >> + ret = 0; >> + return ret; > Same here, does this make sense? > > And wait, you are having userspace grab a kernel lock? What could go > wrong? :( > Yes, this is the bad part of this idea. Tom >> +} >> + >> +static int dfl_uio_release(struct uio_info *info, struct inode *inode) >> +{ >> + int ret = -ENODEV; >> + struct dfl_feature *feature = container_of(info, struct dfl_feature, uio); >> + if (feature->dev) >> + mutex_unlock(&feature->lock); >> + >> + ret = 0; >> + return ret; >> +} >> + >> +static int dfl_uio_irqcontrol(struct uio_info *info, s32 irq_on) >> +{ >> + int ret = -ENODEV; >> + return ret; >> +} >> + >> +int dfl_uio_add(struct dfl_feature *feature) >> +{ >> + struct uio_info *uio = &feature->uio; >> + struct resource *res = >> + &feature->dev->resource[feature->resource_index]; >> + int ret = 0; >> + >> + uio->name = kasprintf(GFP_KERNEL, "dfl-uio-%llx", feature->id); >> + if (!uio->name) { >> + ret = -ENOMEM; >> + goto exit; >> + } >> + >> + uio->version = "0.1"; >> + uio->mem[0].memtype = UIO_MEM_PHYS; >> + uio->mem[0].addr = res->start & PAGE_MASK; >> + uio->mem[0].offs = res->start & ~PAGE_MASK; >> + uio->mem[0].size = (uio->mem[0].offs + resource_size(res) >> + + PAGE_SIZE - 1) & PAGE_MASK; >> + /* How are nr_irqs > 1 handled ??? */ >> + if (feature->nr_irqs == 1) >> + uio->irq = feature->irq_ctx[0].irq; >> + uio->handler = dfl_uio_handler; >> + //uio->mmap = dfl_uio_mmap; > ??? > > I don't understand what this patch is trying to show... > thanks, > > greg k-h >
Hi Tom: On Mon, Dec 07, 2020 at 05:07:05AM -0800, Tom Rix wrote: > > On 12/7/20 12:02 AM, Greg KH wrote: > > On Sun, Dec 06, 2020 at 01:55:54PM -0800, trix@redhat.com wrote: > >> From: Tom Rix <trix@redhat.com> > >> > >> >From [PATCH 0/2] UIO support for dfl devices > >> https://lore.kernel.org/linux-fpga/1602828151-24784-1-git-send-email-yilun.xu@intel.com/ > > Why is this here? > > As reference, Yilun's work has precedence for a uio driver and this rfc is trying to address what i believe is a sticking point of the driver override. This rfc is some code i hacked out to show the idea and move uio support along. I would like to see uio support for at least the unclaimed feature id's because this would make it easier for them to be developed. I see there is concern about sharing DFL devices for both UIO and kernel drivers. Even if a lock could be created to serialize the accesses of both interfaces, they could potentially impact each other without notice on hardware level. Maybe it is better we split the uio driver for unclaimed features. But how we could know it is an unclaimed feature, may be for simplicity we list the feature ids in device id table for dfl uio driver? We should change the code of dfl uio when we want to use uio for a new dfl device, is that acceptable? Thanks, Yilun > > >> Here is an idea to have uio support with no driver override. > >> > >> This makes UIO the primary driver interface because every feature > >> will have one and makes the existing platform driver interface > >> secondary. There will be a new burden for locking write access when > >> they compete. > >> > >> Example shows finding the fpga's temperture. > >> > >> Signed-off-by: Tom Rix <trix@redhat.com> > >> --- > >> drivers/fpga/dfl-fme-main.c | 9 +++- > >> drivers/fpga/dfl-uio.c | 96 +++++++++++++++++++++++++++++++++++++ > >> drivers/fpga/dfl.c | 44 ++++++++++++++++- > >> drivers/fpga/dfl.h | 9 ++++ > >> uio.c | 56 ++++++++++++++++++++++ > >> 5 files changed, 212 insertions(+), 2 deletions(-) > >> create mode 100644 drivers/fpga/dfl-uio.c > >> create mode 100644 uio.c > >> > >> diff --git a/drivers/fpga/dfl-fme-main.c b/drivers/fpga/dfl-fme-main.c > >> index 037dc4f946f0..3323e90a18c4 100644 > >> --- a/drivers/fpga/dfl-fme-main.c > >> +++ b/drivers/fpga/dfl-fme-main.c > >> @@ -709,12 +709,18 @@ static int fme_probe(struct platform_device *pdev) > >> if (ret) > >> goto dev_destroy; > >> > >> - ret = dfl_fpga_dev_ops_register(pdev, &fme_fops, THIS_MODULE); > >> + ret = dfl_fpga_dev_feature_init_uio(pdev, DFH_TYPE_FIU); > >> if (ret) > >> goto feature_uinit; > >> > >> + ret = dfl_fpga_dev_ops_register(pdev, &fme_fops, THIS_MODULE); > >> + if (ret) > >> + goto feature_uinit_uio; > >> + > >> return 0; > >> > >> +feature_uinit_uio: > >> + dfl_fpga_dev_feature_uinit_uio(pdev, DFH_TYPE_FIU); > >> feature_uinit: > >> dfl_fpga_dev_feature_uinit(pdev); > >> dev_destroy: > >> @@ -726,6 +732,7 @@ exit: > >> static int fme_remove(struct platform_device *pdev) > >> { > >> dfl_fpga_dev_ops_unregister(pdev); > >> + dfl_fpga_dev_feature_uinit_uio(pdev, DFH_TYPE_FIU); > >> dfl_fpga_dev_feature_uinit(pdev); > >> fme_dev_destroy(pdev); > >> > >> diff --git a/drivers/fpga/dfl-uio.c b/drivers/fpga/dfl-uio.c > >> new file mode 100644 > >> index 000000000000..7610ee0b19dc > >> --- /dev/null > >> +++ b/drivers/fpga/dfl-uio.c > >> @@ -0,0 +1,96 @@ > >> +/* SPDX-License-Identifier: GPL-2.0 */ > >> +/* > >> + * prototype dfl uio driver > >> + * > >> + * Copyright Tom Rix 2020 > >> + */ > >> +#include <linux/module.h> > >> +#include "dfl.h" > >> + > >> +static irqreturn_t dfl_uio_handler(int irq, struct uio_info *info) > >> +{ > >> + return IRQ_HANDLED; > >> +} > >> + > >> +static int dfl_uio_mmap(struct uio_info *info, struct vm_area_struct *vma) > >> +{ > >> + int ret = -ENODEV; > >> + return ret; > > Did you run this through checkpatch? > > > > Does the code make sense? > > > >> +} > >> + > >> +static int dfl_uio_open(struct uio_info *info, struct inode *inode) > >> +{ > >> + int ret = -ENODEV; > >> + struct dfl_feature *feature = container_of(info, struct dfl_feature, uio); > >> + if (feature->dev) > >> + mutex_lock(&feature->lock); > >> + > >> + ret = 0; > >> + return ret; > > Same here, does this make sense? > > > > And wait, you are having userspace grab a kernel lock? What could go > > wrong? :( > > > Yes, this is the bad part of this idea. > > Tom > > > >> +} > >> + > >> +static int dfl_uio_release(struct uio_info *info, struct inode *inode) > >> +{ > >> + int ret = -ENODEV; > >> + struct dfl_feature *feature = container_of(info, struct dfl_feature, uio); > >> + if (feature->dev) > >> + mutex_unlock(&feature->lock); > >> + > >> + ret = 0; > >> + return ret; > >> +} > >> + > >> +static int dfl_uio_irqcontrol(struct uio_info *info, s32 irq_on) > >> +{ > >> + int ret = -ENODEV; > >> + return ret; > >> +} > >> + > >> +int dfl_uio_add(struct dfl_feature *feature) > >> +{ > >> + struct uio_info *uio = &feature->uio; > >> + struct resource *res = > >> + &feature->dev->resource[feature->resource_index]; > >> + int ret = 0; > >> + > >> + uio->name = kasprintf(GFP_KERNEL, "dfl-uio-%llx", feature->id); > >> + if (!uio->name) { > >> + ret = -ENOMEM; > >> + goto exit; > >> + } > >> + > >> + uio->version = "0.1"; > >> + uio->mem[0].memtype = UIO_MEM_PHYS; > >> + uio->mem[0].addr = res->start & PAGE_MASK; > >> + uio->mem[0].offs = res->start & ~PAGE_MASK; > >> + uio->mem[0].size = (uio->mem[0].offs + resource_size(res) > >> + + PAGE_SIZE - 1) & PAGE_MASK; > >> + /* How are nr_irqs > 1 handled ??? */ > >> + if (feature->nr_irqs == 1) > >> + uio->irq = feature->irq_ctx[0].irq; > >> + uio->handler = dfl_uio_handler; > >> + //uio->mmap = dfl_uio_mmap; > > ??? > > > > I don't understand what this patch is trying to show... > > thanks, > > > > greg k-h > >
On 12/9/20 12:56 AM, Xu Yilun wrote: > Hi Tom: > > On Mon, Dec 07, 2020 at 05:07:05AM -0800, Tom Rix wrote: >> On 12/7/20 12:02 AM, Greg KH wrote: >>> On Sun, Dec 06, 2020 at 01:55:54PM -0800, trix@redhat.com wrote: >>>> From: Tom Rix <trix@redhat.com> >>>> >>>> >From [PATCH 0/2] UIO support for dfl devices >>>> https://lore.kernel.org/linux-fpga/1602828151-24784-1-git-send-email-yilun.xu@intel.com/ >>> Why is this here? >> As reference, Yilun's work has precedence for a uio driver and this rfc is trying to address what i believe is a sticking point of the driver override. This rfc is some code i hacked out to show the idea and move uio support along. I would like to see uio support for at least the unclaimed feature id's because this would make it easier for them to be developed. > I see there is concern about sharing DFL devices for both UIO and kernel > drivers. Even if a lock could be created to serialize the accesses of > both interfaces, they could potentially impact each other without notice > on hardware level. > > Maybe it is better we split the uio driver for unclaimed features. But > how we could know it is an unclaimed feature, may be for simplicity we > list the feature ids in device id table for dfl uio driver? We should > change the code of dfl uio when we want to use uio for a new dfl device, > is that acceptable? No entry in the device id table would mean there would never be a conflict, so this is good. This set could be expanded if the platform device driver was checked, and then uio could also used whose platform drivers were disabled in the configury. There would be this problem: on the module case, disabling uio per feature so the platform driver kmod could be used. I think we could do your the device id table suggestion now since it is simple and will help almost all developers. Tom > > Thanks, > Yilun > >>>> Here is an idea to have uio support with no driver override. >>>> >>>> This makes UIO the primary driver interface because every feature >>>> will have one and makes the existing platform driver interface >>>> secondary. There will be a new burden for locking write access when >>>> they compete. >>>> >>>> Example shows finding the fpga's temperture. >>>> >>>> Signed-off-by: Tom Rix <trix@redhat.com> >>>> --- >>>> drivers/fpga/dfl-fme-main.c | 9 +++- >>>> drivers/fpga/dfl-uio.c | 96 +++++++++++++++++++++++++++++++++++++ >>>> drivers/fpga/dfl.c | 44 ++++++++++++++++- >>>> drivers/fpga/dfl.h | 9 ++++ >>>> uio.c | 56 ++++++++++++++++++++++ >>>> 5 files changed, 212 insertions(+), 2 deletions(-) >>>> create mode 100644 drivers/fpga/dfl-uio.c >>>> create mode 100644 uio.c >>>> >>>> diff --git a/drivers/fpga/dfl-fme-main.c b/drivers/fpga/dfl-fme-main.c >>>> index 037dc4f946f0..3323e90a18c4 100644 >>>> --- a/drivers/fpga/dfl-fme-main.c >>>> +++ b/drivers/fpga/dfl-fme-main.c >>>> @@ -709,12 +709,18 @@ static int fme_probe(struct platform_device *pdev) >>>> if (ret) >>>> goto dev_destroy; >>>> >>>> - ret = dfl_fpga_dev_ops_register(pdev, &fme_fops, THIS_MODULE); >>>> + ret = dfl_fpga_dev_feature_init_uio(pdev, DFH_TYPE_FIU); >>>> if (ret) >>>> goto feature_uinit; >>>> >>>> + ret = dfl_fpga_dev_ops_register(pdev, &fme_fops, THIS_MODULE); >>>> + if (ret) >>>> + goto feature_uinit_uio; >>>> + >>>> return 0; >>>> >>>> +feature_uinit_uio: >>>> + dfl_fpga_dev_feature_uinit_uio(pdev, DFH_TYPE_FIU); >>>> feature_uinit: >>>> dfl_fpga_dev_feature_uinit(pdev); >>>> dev_destroy: >>>> @@ -726,6 +732,7 @@ exit: >>>> static int fme_remove(struct platform_device *pdev) >>>> { >>>> dfl_fpga_dev_ops_unregister(pdev); >>>> + dfl_fpga_dev_feature_uinit_uio(pdev, DFH_TYPE_FIU); >>>> dfl_fpga_dev_feature_uinit(pdev); >>>> fme_dev_destroy(pdev); >>>> >>>> diff --git a/drivers/fpga/dfl-uio.c b/drivers/fpga/dfl-uio.c >>>> new file mode 100644 >>>> index 000000000000..7610ee0b19dc >>>> --- /dev/null >>>> +++ b/drivers/fpga/dfl-uio.c >>>> @@ -0,0 +1,96 @@ >>>> +/* SPDX-License-Identifier: GPL-2.0 */ >>>> +/* >>>> + * prototype dfl uio driver >>>> + * >>>> + * Copyright Tom Rix 2020 >>>> + */ >>>> +#include <linux/module.h> >>>> +#include "dfl.h" >>>> + >>>> +static irqreturn_t dfl_uio_handler(int irq, struct uio_info *info) >>>> +{ >>>> + return IRQ_HANDLED; >>>> +} >>>> + >>>> +static int dfl_uio_mmap(struct uio_info *info, struct vm_area_struct *vma) >>>> +{ >>>> + int ret = -ENODEV; >>>> + return ret; >>> Did you run this through checkpatch? >>> >>> Does the code make sense? >>> >>>> +} >>>> + >>>> +static int dfl_uio_open(struct uio_info *info, struct inode *inode) >>>> +{ >>>> + int ret = -ENODEV; >>>> + struct dfl_feature *feature = container_of(info, struct dfl_feature, uio); >>>> + if (feature->dev) >>>> + mutex_lock(&feature->lock); >>>> + >>>> + ret = 0; >>>> + return ret; >>> Same here, does this make sense? >>> >>> And wait, you are having userspace grab a kernel lock? What could go >>> wrong? :( >>> >> Yes, this is the bad part of this idea. >> >> Tom >> >> >>>> +} >>>> + >>>> +static int dfl_uio_release(struct uio_info *info, struct inode *inode) >>>> +{ >>>> + int ret = -ENODEV; >>>> + struct dfl_feature *feature = container_of(info, struct dfl_feature, uio); >>>> + if (feature->dev) >>>> + mutex_unlock(&feature->lock); >>>> + >>>> + ret = 0; >>>> + return ret; >>>> +} >>>> + >>>> +static int dfl_uio_irqcontrol(struct uio_info *info, s32 irq_on) >>>> +{ >>>> + int ret = -ENODEV; >>>> + return ret; >>>> +} >>>> + >>>> +int dfl_uio_add(struct dfl_feature *feature) >>>> +{ >>>> + struct uio_info *uio = &feature->uio; >>>> + struct resource *res = >>>> + &feature->dev->resource[feature->resource_index]; >>>> + int ret = 0; >>>> + >>>> + uio->name = kasprintf(GFP_KERNEL, "dfl-uio-%llx", feature->id); >>>> + if (!uio->name) { >>>> + ret = -ENOMEM; >>>> + goto exit; >>>> + } >>>> + >>>> + uio->version = "0.1"; >>>> + uio->mem[0].memtype = UIO_MEM_PHYS; >>>> + uio->mem[0].addr = res->start & PAGE_MASK; >>>> + uio->mem[0].offs = res->start & ~PAGE_MASK; >>>> + uio->mem[0].size = (uio->mem[0].offs + resource_size(res) >>>> + + PAGE_SIZE - 1) & PAGE_MASK; >>>> + /* How are nr_irqs > 1 handled ??? */ >>>> + if (feature->nr_irqs == 1) >>>> + uio->irq = feature->irq_ctx[0].irq; >>>> + uio->handler = dfl_uio_handler; >>>> + //uio->mmap = dfl_uio_mmap; >>> ??? >>> >>> I don't understand what this patch is trying to show... >>> thanks, >>> >>> greg k-h >>>
diff --git a/drivers/fpga/dfl-fme-main.c b/drivers/fpga/dfl-fme-main.c index 037dc4f946f0..3323e90a18c4 100644 --- a/drivers/fpga/dfl-fme-main.c +++ b/drivers/fpga/dfl-fme-main.c @@ -709,12 +709,18 @@ static int fme_probe(struct platform_device *pdev) if (ret) goto dev_destroy; - ret = dfl_fpga_dev_ops_register(pdev, &fme_fops, THIS_MODULE); + ret = dfl_fpga_dev_feature_init_uio(pdev, DFH_TYPE_FIU); if (ret) goto feature_uinit; + ret = dfl_fpga_dev_ops_register(pdev, &fme_fops, THIS_MODULE); + if (ret) + goto feature_uinit_uio; + return 0; +feature_uinit_uio: + dfl_fpga_dev_feature_uinit_uio(pdev, DFH_TYPE_FIU); feature_uinit: dfl_fpga_dev_feature_uinit(pdev); dev_destroy: @@ -726,6 +732,7 @@ exit: static int fme_remove(struct platform_device *pdev) { dfl_fpga_dev_ops_unregister(pdev); + dfl_fpga_dev_feature_uinit_uio(pdev, DFH_TYPE_FIU); dfl_fpga_dev_feature_uinit(pdev); fme_dev_destroy(pdev); diff --git a/drivers/fpga/dfl-uio.c b/drivers/fpga/dfl-uio.c new file mode 100644 index 000000000000..7610ee0b19dc --- /dev/null +++ b/drivers/fpga/dfl-uio.c @@ -0,0 +1,96 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * prototype dfl uio driver + * + * Copyright Tom Rix 2020 + */ +#include <linux/module.h> +#include "dfl.h" + +static irqreturn_t dfl_uio_handler(int irq, struct uio_info *info) +{ + return IRQ_HANDLED; +} + +static int dfl_uio_mmap(struct uio_info *info, struct vm_area_struct *vma) +{ + int ret = -ENODEV; + return ret; +} + +static int dfl_uio_open(struct uio_info *info, struct inode *inode) +{ + int ret = -ENODEV; + struct dfl_feature *feature = container_of(info, struct dfl_feature, uio); + if (feature->dev) + mutex_lock(&feature->lock); + + ret = 0; + return ret; +} + +static int dfl_uio_release(struct uio_info *info, struct inode *inode) +{ + int ret = -ENODEV; + struct dfl_feature *feature = container_of(info, struct dfl_feature, uio); + if (feature->dev) + mutex_unlock(&feature->lock); + + ret = 0; + return ret; +} + +static int dfl_uio_irqcontrol(struct uio_info *info, s32 irq_on) +{ + int ret = -ENODEV; + return ret; +} + +int dfl_uio_add(struct dfl_feature *feature) +{ + struct uio_info *uio = &feature->uio; + struct resource *res = + &feature->dev->resource[feature->resource_index]; + int ret = 0; + + uio->name = kasprintf(GFP_KERNEL, "dfl-uio-%llx", feature->id); + if (!uio->name) { + ret = -ENOMEM; + goto exit; + } + + uio->version = "0.1"; + uio->mem[0].memtype = UIO_MEM_PHYS; + uio->mem[0].addr = res->start & PAGE_MASK; + uio->mem[0].offs = res->start & ~PAGE_MASK; + uio->mem[0].size = (uio->mem[0].offs + resource_size(res) + + PAGE_SIZE - 1) & PAGE_MASK; + /* How are nr_irqs > 1 handled ??? */ + if (feature->nr_irqs == 1) + uio->irq = feature->irq_ctx[0].irq; + uio->handler = dfl_uio_handler; + //uio->mmap = dfl_uio_mmap; + uio->open = dfl_uio_open; + uio->release = dfl_uio_release; + uio->irqcontrol = dfl_uio_irqcontrol; + + ret = uio_register_device(&feature->dev->dev, uio); + if (ret) + goto err_register; + +exit: + return ret; +err_register: + kfree(uio->name); + goto exit; +} +EXPORT_SYMBOL_GPL(dfl_uio_add); + +int dfl_uio_remove(struct dfl_feature *feature) +{ + uio_unregister_device(&feature->uio); + kfree(feature->uio.name); + return 0; +} +EXPORT_SYMBOL_GPL(dfl_uio_remove); + diff --git a/drivers/fpga/dfl.c b/drivers/fpga/dfl.c index 1305be48037d..af2cd3d1b5f6 100644 --- a/drivers/fpga/dfl.c +++ b/drivers/fpga/dfl.c @@ -603,6 +603,7 @@ static int dfl_feature_instance_init(struct platform_device *pdev, } feature->ops = drv->ops; + mutex_init(&feature->lock); return ret; } @@ -663,10 +664,51 @@ exit: } EXPORT_SYMBOL_GPL(dfl_fpga_dev_feature_init); +int dfl_fpga_dev_feature_init_uio(struct platform_device *pdev, int dfh_type) { + struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev); + struct dfl_feature *feature; + int ret; + + dfl_fpga_dev_for_each_feature(pdata, feature) { + if (dfh_type == DFH_TYPE_FIU) { + if (feature->id == FEATURE_ID_FIU_HEADER || + feature->id == FEATURE_ID_AFU) + continue; + + ret = dfl_uio_add(feature); + if (ret) + goto exit; + } + } + + return 0; +exit: + dfl_fpga_dev_feature_uinit_uio(pdev, dfh_type); + return ret; +} +EXPORT_SYMBOL_GPL(dfl_fpga_dev_feature_init_uio); + +int dfl_fpga_dev_feature_uinit_uio(struct platform_device *pdev, int dfh_type) { + struct dfl_feature_platform_data *pdata = dev_get_platdata(&pdev->dev); + struct dfl_feature *feature; + int ret = 0; + + dfl_fpga_dev_for_each_feature(pdata, feature) { + if (dfh_type == DFH_TYPE_FIU) { + if (feature->id == FEATURE_ID_FIU_HEADER || + feature->id == FEATURE_ID_AFU) + continue; + + ret |= dfl_uio_remove(feature); + } + } + return ret; +} +EXPORT_SYMBOL_GPL(dfl_fpga_dev_feature_uinit_uio); + static void dfl_chardev_uinit(void) { int i; - for (i = 0; i < DFL_FPGA_DEVT_MAX; i++) if (MAJOR(dfl_chrdevs[i].devt)) { unregister_chrdev_region(dfl_chrdevs[i].devt, diff --git a/drivers/fpga/dfl.h b/drivers/fpga/dfl.h index a85d1cd7a130..fde0fc902d4d 100644 --- a/drivers/fpga/dfl.h +++ b/drivers/fpga/dfl.h @@ -26,6 +26,7 @@ #include <linux/platform_device.h> #include <linux/slab.h> #include <linux/uuid.h> +#include <linux/uio_driver.h> #include <linux/fpga/fpga-region.h> /* maximum supported number of ports */ @@ -232,6 +233,7 @@ struct dfl_feature_irq_ctx { * struct dfl_feature - sub feature of the feature devices * * @dev: ptr to pdev of the feature device which has the sub feature. + * @uio: uio interface for feature. * @id: sub feature id. * @index: unique identifier for an sub feature within the feature device. * It is possible that multiply sub features with same feature id are @@ -248,6 +250,8 @@ struct dfl_feature_irq_ctx { */ struct dfl_feature { struct platform_device *dev; + struct uio_info uio; + struct mutex lock; /* serialize dev and uio */ u64 id; int index; int resource_index; @@ -360,6 +364,11 @@ void dfl_fpga_dev_feature_uinit(struct platform_device *pdev); int dfl_fpga_dev_feature_init(struct platform_device *pdev, struct dfl_feature_driver *feature_drvs); +int dfl_fpga_dev_feature_init_uio(struct platform_device *pdev, int dfh_type); +int dfl_fpga_dev_feature_uinit_uio(struct platform_device *pdev, int dfh_type); +int dfl_uio_add(struct dfl_feature *feature); +int dfl_uio_remove(struct dfl_feature *feature); + int dfl_fpga_dev_ops_register(struct platform_device *pdev, const struct file_operations *fops, struct module *owner); diff --git a/uio.c b/uio.c new file mode 100644 index 000000000000..50210aab4822 --- /dev/null +++ b/uio.c @@ -0,0 +1,56 @@ +#include <stdlib.h> +#include <stdio.h> +#include <unistd.h> +#include <sys/mman.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <errno.h> +#include <stdint.h> + +int main() +{ + int fd; + uint64_t *ptr; + unsigned page_size=sysconf(_SC_PAGESIZE); + struct stat sb; + + /* + * this is fid 1, thermal mgt + * ex/ + * # cat /sys/class/hwmon/hwmon3/temp1_input + * 39000 + */ + fd = open("/dev/uio0", O_RDONLY|O_SYNC); + if (fd < 0) { + perror("uio open:"); + return errno; + } + + ptr = (uint64_t *) mmap(NULL, page_size, PROT_READ, MAP_SHARED, fd, 0); + if (!ptr) { + perror("uio mmap:"); + } else { + + /* from dfl-fme-main.c : + * + * #define FME_THERM_RDSENSOR_FMT1 0x10 + * #define FPGA_TEMPERATURE GENMASK_ULL(6, 0) + * + * case hwmon_temp_input: + * v = readq(feature->ioaddr + FME_THERM_RDSENSOR_FMT1); + * *val = (long)(FIELD_GET(FPGA_TEMPERATURE, v) * 1000); + * break; + */ + uint64_t v = ptr[2]; + v &= (1 << 6) -1; + v *= 1000; + printf("Temperature %d\n", v); + + munmap(ptr, page_size); + } + if (close(fd)) + perror("uio close:"); + + return errno; +}