| Message ID | 1432251450-26352-2-git-send-email-moritz.fischer@ettus.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Moritz, Overall looks good some nitpicks below. On Fri, May 22, 2015 at 5:07 AM, Moritz Fischer <moritz.fischer@ettus.com> wrote: > The Xilinx LogiCORE IP mailbox is a FPGA core that allows for > interprocessor communication via AXI4 memory mapped / AXI4 stream > interfaces. > > It is single channel per core and allows for transmit and receive. > > Signed-off-by: Moritz Fischer <moritz.fischer@ettus.com> > --- > drivers/mailbox/Kconfig | 8 + > drivers/mailbox/Makefile | 2 + > drivers/mailbox/mailbox-xilinx.c | 339 ++++++++++++++++++++++++++++++++++ > 3 files changed, 349 insertions(+) > > diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig > index 84b0a2d..e11e4b2 100644 > --- a/drivers/mailbox/Kconfig > +++ b/drivers/mailbox/Kconfig > @@ -60,4 +60,12 @@ config ALTERA_MBOX > An implementation of the Altera Mailbox soft core. It is used > to send message between processors. Say Y here if you want to use the > Altera mailbox support. > + > +config XILINX_MBOX > + tristate "Xilinx Mailbox" > + help > + An implementation of the Xilinx Mailbox soft core. It is used > + to send message between processors. Say Y here if you want to use the > + Xilinx mailbox support. > + > endif > diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile > index b18201e..d28a028 100644 > --- a/drivers/mailbox/Makefile > +++ b/drivers/mailbox/Makefile > @@ -11,3 +11,5 @@ obj-$(CONFIG_OMAP2PLUS_MBOX) += omap-mailbox.o > obj-$(CONFIG_PCC) += pcc.o > > obj-$(CONFIG_ALTERA_MBOX) += mailbox-altera.o > + > +obj-$(CONFIG_XILINX_MBOX) += mailbox-xilinx.o > diff --git a/drivers/mailbox/mailbox-xilinx.c b/drivers/mailbox/mailbox-xilinx.c > new file mode 100644 > index 0000000..8d8aa17 > --- /dev/null > +++ b/drivers/mailbox/mailbox-xilinx.c > @@ -0,0 +1,339 @@ > +/* > + * Copyright (c) 2015, National Instruments Corp. All rights reserved. > + * > + * Driver for the Xilinx Logicore mailbox IP block > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; version 2 of the License. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + */ > + > +#include <linux/device.h> > +#include <linux/interrupt.h> > +#include <linux/io.h> > +#include <linux/kernel.h> > +#include <linux/mailbox_controller.h> > +#include <linux/module.h> > +#include <linux/of.h> > +#include <linux/platform_device.h> > + > +#define DRIVER_NAME "xilinx-mailbox" > + > +/* register offsets */ > +#define MAILBOX_REG_WRDATA 0x00 > +#define MAILBOX_REG_RDDATA 0x08 > +#define MAILBOX_REG_STATUS 0x10 > +#define MAILBOX_REG_ERROR 0x14 > +#define MAILBOX_REG_SIT 0x18 > +#define MAILBOX_REG_RIT 0x1c > +#define MAILBOX_REG_IS 0x20 > +#define MAILBOX_REG_IE 0x24 > +#define MAILBOX_REG_IP 0x28 > + > +/* status register */ > +#define STS_RTA BIT(3) > +#define STS_STA BIT(2) > +#define STS_FULL BIT(1) > +#define STS_EMPTY BIT(0) > + > +/* error register */ > +#define ERR_FULL BIT(1) > +#define ERR_EMPTY BIT(0) > + > +/* mailbox interrupt status register */ > +#define INT_STATUS_ERR BIT(2) > +#define INT_STATUS_RTI BIT(1) > +#define INT_STATUS_STI BIT(0) > + > +/* mailbox interrupt enable register */ > +#define INT_ENABLE_ERR BIT(2) > +#define INT_ENABLE_RTI BIT(1) > +#define INT_ENABLE_STI BIT(0) > + > +#define MBOX_POLLING_MS 5 /* polling interval 5ms */ > + > +struct xilinx_mbox { > + bool intr_mode; > + int irq; > + void __iomem *mbox_base; > + struct device *dev; > + struct mbox_controller controller; > + > + /* if the controller supports only RX polling mode */ > + struct timer_list rxpoll_timer; > +}; > + > +static struct xilinx_mbox *mbox_chan_to_xilinx_mbox(struct mbox_chan *chan) > +{ > + if (!chan || !chan->con_priv) > + return NULL; > + > + return (struct xilinx_mbox *)chan->con_priv; > +} > + > +static inline int xilinx_mbox_full(struct xilinx_mbox *mbox) Should this be a bool ? > +{ > + u32 status; > + > + status = readl_relaxed(mbox->mbox_base + MAILBOX_REG_STATUS); > + return status & STS_FULL; > +} > + > +static inline int xilinx_mbox_pending(struct xilinx_mbox *mbox) > +{ > + u32 status; > + > + status = readl_relaxed(mbox->mbox_base + MAILBOX_REG_STATUS); > + return !(status & STS_EMPTY); > +} > + > +static void xilinx_mbox_rx_intmask(struct xilinx_mbox *mbox, bool enable) > +{ > + u32 mask; > + > + mask = readl_relaxed(mbox->mbox_base + MAILBOX_REG_IE); > + if (enable) > + mask |= INT_ENABLE_RTI; > + else > + mask &= ~INT_ENABLE_RTI; > + writel_relaxed(mask, mbox->mbox_base + MAILBOX_REG_IE); > +} > + > +static void xilinx_mbox_tx_intmask(struct xilinx_mbox *mbox, bool enable) > +{ > + u32 mask; > + > + mask = readl_relaxed(mbox->mbox_base + MAILBOX_REG_IE); > + if (enable) > + mask |= INT_ENABLE_STI; > + else > + mask &= ~INT_ENABLE_STI; > + writel_relaxed(mask, mbox->mbox_base + MAILBOX_REG_IE); > +} May be the two functions xilinx_mbox_rx_intmask / xilinx_mbox_tx_intmask could be combined. That way if the err also needs to be enabled another function will not be needed. > + > +static void xilinx_mbox_rx_data(struct mbox_chan *chan) > +{ > + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); > + u32 data; > + > + if (xilinx_mbox_pending(mbox)) { > + data = readl_relaxed(mbox->mbox_base + MAILBOX_REG_RDDATA); > + mbox_chan_received_data(chan, (void *)data); > + } > +} > + > +static void xilinx_mbox_poll_rx(unsigned long data) > +{ > + struct mbox_chan *chan = (struct mbox_chan *)data; > + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); > + > + xilinx_mbox_rx_data(chan); > + > + mod_timer(&mbox->rxpoll_timer, > + jiffies + msecs_to_jiffies(MBOX_POLLING_MS)); > +} > + > +static irqreturn_t xilinx_mbox_interrupt(int irq, void *p) > +{ > + u32 mask; > + struct mbox_chan *chan = (struct mbox_chan *)p; > + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); > + > + mask = readl_relaxed(mbox->mbox_base + MAILBOX_REG_IS); > + if (mask & INT_STATUS_RTI) > + xilinx_mbox_rx_data(chan); > + > + /* mask irqs *before* notifying done, require tx_block=true */ > + if (mask & INT_STATUS_STI) { > + xilinx_mbox_tx_intmask(mbox, false); > + mbox_chan_txdone(chan, 0); > + } > + > + if (mask & INT_STATUS_ERR) > + dev_err(mbox->dev, "Got error IRQ!\n"); I think we never enabled the status error. > + > + writel_relaxed(mask, mbox->mbox_base + MAILBOX_REG_IS); > + return IRQ_HANDLED; > +} > + > +static int xilinx_mbox_startup(struct mbox_chan *chan) > +{ > + int ret; > + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); > + > + if (mbox->intr_mode) { > + ret = request_irq(mbox->irq, xilinx_mbox_interrupt, 0, > + dev_name(mbox->dev), chan); > + if (unlikely(ret)) { > + dev_err(mbox->dev, > + "failed to register mailbox interrupt:%d\n", > + ret); > + mbox->intr_mode = false; > + goto polling; /* use polling if failed */ > + } > + > + xilinx_mbox_rx_intmask(mbox, true); > + } > + > +polling: > + /* setup polling timer */ > + setup_timer(&mbox->rxpoll_timer, xilinx_mbox_poll_rx, > + (unsigned long)chan); > + mod_timer(&mbox->rxpoll_timer, > + jiffies + msecs_to_jiffies(MBOX_POLLING_MS)); > + > + return 0; > +} > + > +static int xilinx_mbox_send_data(struct mbox_chan *chan, void *data) > +{ > + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); > + u32 *udata = (u32 *)data; > + > + if (!mbox || !data) > + return -EINVAL; > + > + if (xilinx_mbox_full(mbox)) > + return -EBUSY; > + > + /* enable interrupt before send */ > + if (mbox->intr_mode) > + xilinx_mbox_tx_intmask(mbox, true); > + > + writel_relaxed(*udata, mbox->mbox_base + MAILBOX_REG_WRDATA); > + > + return 0; > +} > + > +static bool xilinx_mbox_last_tx_done(struct mbox_chan *chan) > +{ > + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); > + > + /* return false if mailbox is full */ > + return xilinx_mbox_full(mbox) ? false : true; A complement would have been consistent with the other places > +} > + > +static bool xilinx_mbox_peek_data(struct mbox_chan *chan) > +{ > + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); > + > + return xilinx_mbox_pending(mbox) ? true : false; > +} > + > +static void xilinx_mbox_shutdown(struct mbox_chan *chan) > +{ > + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); > + > + if (mbox->intr_mode) { > + /* unmask all interrupt masks */ > + writel_relaxed(~0, mbox->mbox_base + MAILBOX_REG_IE); Not sure why we unmask the interrupts and free the irq. Am I missing something. > + free_irq(mbox->irq, chan); > + } else > + del_timer_sync(&mbox->rxpoll_timer); > +} > + > +static struct mbox_chan_ops xilinx_mbox_ops = { > + .send_data = xilinx_mbox_send_data, > + .startup = xilinx_mbox_startup, > + .shutdown = xilinx_mbox_shutdown, > + .last_tx_done = xilinx_mbox_last_tx_done, > + .peek_data = xilinx_mbox_peek_data, > +}; > + > +static int xilinx_mbox_probe(struct platform_device *pdev) > +{ > + struct xilinx_mbox *mbox; > + struct resource *regs; > + struct mbox_chan *chans; > + int ret; > + > + mbox = devm_kzalloc(&pdev->dev, sizeof(*mbox), > + GFP_KERNEL); > + if (!mbox) > + return -ENOMEM; > + > + /* allocated one channel */ > + chans = devm_kzalloc(&pdev->dev, sizeof(*chans), GFP_KERNEL); > + if (!chans) > + return -ENOMEM; > + > + regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + > + mbox->mbox_base = devm_ioremap_resource(&pdev->dev, regs); > + if (IS_ERR(mbox->mbox_base)) > + return PTR_ERR(mbox->mbox_base); > + > + mbox->irq = platform_get_irq(pdev, 0); > + /* if irq is present, we can use it, otherwise, poll */ > + if (mbox->irq >= 0) > + mbox->intr_mode = true; > + else > + dev_info(&pdev->dev, "IRQ not found, fallback to polling.\n"); > + > + mbox->dev = &pdev->dev; > + > + /* Hardware supports only one channel. */ > + chans[0].con_priv = mbox; > + mbox->controller.dev = mbox->dev; > + mbox->controller.num_chans = 1; > + mbox->controller.chans = chans; > + mbox->controller.ops = &xilinx_mbox_ops; > + > + if (mbox->intr_mode) { > + mbox->controller.txdone_irq = true; > + } else { > + mbox->controller.txdone_poll = true; > + mbox->controller.txpoll_period = MBOX_POLLING_MS; > + } > + > + ret = mbox_controller_register(&mbox->controller); > + if (ret) { > + dev_err(&pdev->dev, "Register mailbox failed\n"); > + goto err; the goto could be avoided. > + } > + > + platform_set_drvdata(pdev, mbox); > +err: > + return ret; > +} > + > + > +static int xilinx_mbox_remove(struct platform_device *pdev) > +{ > + struct xilinx_mbox *mbox = platform_get_drvdata(pdev); > + > + if (!mbox) > + return -EINVAL; > + > + mbox_controller_unregister(&mbox->controller); > + > + return 0; > +} > + > +static const struct of_device_id xilinx_mbox_match[] = { > + { .compatible = "xlnx,mailbox-2.1" }, > + { /* Sentinel */ } > +}; > + > +MODULE_DEVICE_TABLE(of, xilinx_mbox_match); > + > +static struct platform_driver xilinx_mbox_driver = { > + .probe = xilinx_mbox_probe, > + .remove = xilinx_mbox_remove, > + .driver = { > + .name = DRIVER_NAME, > + .of_match_table = xilinx_mbox_match, > + }, > +}; > + > +module_platform_driver(xilinx_mbox_driver); > + > +MODULE_LICENSE("GPL v2"); > +MODULE_DESCRIPTION("Xilinx mailbox specific functions"); > +MODULE_AUTHOR("Moritz Fischer <moritz.fischer@ettus.com>"); > +MODULE_ALIAS("platform:xilinx-mailbox"); > -- > 2.4.1 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
On 05/22/2015 01:37 AM, Moritz Fischer wrote: > The Xilinx LogiCORE IP mailbox is a FPGA core that allows for > interprocessor communication via AXI4 memory mapped / AXI4 stream > interfaces. > > It is single channel per core and allows for transmit and receive. > > Signed-off-by: Moritz Fischer <moritz.fischer@ettus.com> > --- > drivers/mailbox/Kconfig | 8 + > drivers/mailbox/Makefile | 2 + > drivers/mailbox/mailbox-xilinx.c | 339 ++++++++++++++++++++++++++++++++++ > 3 files changed, 349 insertions(+) > > diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig > index 84b0a2d..e11e4b2 100644 > --- a/drivers/mailbox/Kconfig > +++ b/drivers/mailbox/Kconfig > @@ -60,4 +60,12 @@ config ALTERA_MBOX > An implementation of the Altera Mailbox soft core. It is used > to send message between processors. Say Y here if you want to use the > Altera mailbox support. > + > +config XILINX_MBOX > + tristate "Xilinx Mailbox" > + help > + An implementation of the Xilinx Mailbox soft core. It is used > + to send message between processors. Say Y here if you want to use the > + Xilinx mailbox support. > + > endif > diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile > index b18201e..d28a028 100644 > --- a/drivers/mailbox/Makefile > +++ b/drivers/mailbox/Makefile > @@ -11,3 +11,5 @@ obj-$(CONFIG_OMAP2PLUS_MBOX) += omap-mailbox.o > obj-$(CONFIG_PCC) += pcc.o > > obj-$(CONFIG_ALTERA_MBOX) += mailbox-altera.o > + > +obj-$(CONFIG_XILINX_MBOX) += mailbox-xilinx.o > diff --git a/drivers/mailbox/mailbox-xilinx.c b/drivers/mailbox/mailbox-xilinx.c > new file mode 100644 > index 0000000..8d8aa17 > --- /dev/null > +++ b/drivers/mailbox/mailbox-xilinx.c > @@ -0,0 +1,339 @@ > +/* > + * Copyright (c) 2015, National Instruments Corp. All rights reserved. > + * > + * Driver for the Xilinx Logicore mailbox IP block > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; version 2 of the License. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + */ > + > +#include <linux/device.h> > +#include <linux/interrupt.h> > +#include <linux/io.h> > +#include <linux/kernel.h> > +#include <linux/mailbox_controller.h> > +#include <linux/module.h> > +#include <linux/of.h> > +#include <linux/platform_device.h> > + > +#define DRIVER_NAME "xilinx-mailbox" > + > +/* register offsets */ > +#define MAILBOX_REG_WRDATA 0x00 I prefer to use #define<space>macro_name<tab>value but up to you. > +#define MAILBOX_REG_RDDATA 0x08 > +#define MAILBOX_REG_STATUS 0x10 > +#define MAILBOX_REG_ERROR 0x14 > +#define MAILBOX_REG_SIT 0x18 > +#define MAILBOX_REG_RIT 0x1c > +#define MAILBOX_REG_IS 0x20 > +#define MAILBOX_REG_IE 0x24 > +#define MAILBOX_REG_IP 0x28 > + > +/* status register */ > +#define STS_RTA BIT(3) > +#define STS_STA BIT(2) > +#define STS_FULL BIT(1) > +#define STS_EMPTY BIT(0) > + > +/* error register */ > +#define ERR_FULL BIT(1) > +#define ERR_EMPTY BIT(0) > + > +/* mailbox interrupt status register */ > +#define INT_STATUS_ERR BIT(2) > +#define INT_STATUS_RTI BIT(1) > +#define INT_STATUS_STI BIT(0) > + > +/* mailbox interrupt enable register */ > +#define INT_ENABLE_ERR BIT(2) > +#define INT_ENABLE_RTI BIT(1) > +#define INT_ENABLE_STI BIT(0) > + > +#define MBOX_POLLING_MS 5 /* polling interval 5ms */ and you are using tab here - it looks like c&p from somewhere. :-) > + > +struct xilinx_mbox { > + bool intr_mode; look below. > + int irq; > + void __iomem *mbox_base; > + struct device *dev; > + struct mbox_controller controller; > + > + /* if the controller supports only RX polling mode */ > + struct timer_list rxpoll_timer; > +}; > + > +static struct xilinx_mbox *mbox_chan_to_xilinx_mbox(struct mbox_chan *chan) > +{ > + if (!chan || !chan->con_priv) > + return NULL; > + > + return (struct xilinx_mbox *)chan->con_priv; > +} > + > +static inline int xilinx_mbox_full(struct xilinx_mbox *mbox) > +{ > + u32 status; > + > + status = readl_relaxed(mbox->mbox_base + MAILBOX_REG_STATUS); empty line here please for easier reading. > + return status & STS_FULL; > +} > + > +static inline int xilinx_mbox_pending(struct xilinx_mbox *mbox) > +{ > + u32 status; > + > + status = readl_relaxed(mbox->mbox_base + MAILBOX_REG_STATUS); ditto. > + return !(status & STS_EMPTY); > +} > + > +static void xilinx_mbox_rx_intmask(struct xilinx_mbox *mbox, bool enable) > +{ > + u32 mask; > + > + mask = readl_relaxed(mbox->mbox_base + MAILBOX_REG_IE); > + if (enable) > + mask |= INT_ENABLE_RTI; > + else > + mask &= ~INT_ENABLE_RTI; > + writel_relaxed(mask, mbox->mbox_base + MAILBOX_REG_IE); > +} > + > +static void xilinx_mbox_tx_intmask(struct xilinx_mbox *mbox, bool enable) > +{ > + u32 mask; > + > + mask = readl_relaxed(mbox->mbox_base + MAILBOX_REG_IE); > + if (enable) > + mask |= INT_ENABLE_STI; > + else > + mask &= ~INT_ENABLE_STI; > + writel_relaxed(mask, mbox->mbox_base + MAILBOX_REG_IE); > +} > + > +static void xilinx_mbox_rx_data(struct mbox_chan *chan) > +{ > + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); > + u32 data; > + > + if (xilinx_mbox_pending(mbox)) { > + data = readl_relaxed(mbox->mbox_base + MAILBOX_REG_RDDATA); > + mbox_chan_received_data(chan, (void *)data); > + } > +} > + > +static void xilinx_mbox_poll_rx(unsigned long data) > +{ > + struct mbox_chan *chan = (struct mbox_chan *)data; > + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); > + > + xilinx_mbox_rx_data(chan); > + > + mod_timer(&mbox->rxpoll_timer, > + jiffies + msecs_to_jiffies(MBOX_POLLING_MS)); > +} > + > +static irqreturn_t xilinx_mbox_interrupt(int irq, void *p) > +{ > + u32 mask; > + struct mbox_chan *chan = (struct mbox_chan *)p; > + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); > + > + mask = readl_relaxed(mbox->mbox_base + MAILBOX_REG_IS); > + if (mask & INT_STATUS_RTI) > + xilinx_mbox_rx_data(chan); > + > + /* mask irqs *before* notifying done, require tx_block=true */ > + if (mask & INT_STATUS_STI) { > + xilinx_mbox_tx_intmask(mbox, false); > + mbox_chan_txdone(chan, 0); > + } > + > + if (mask & INT_STATUS_ERR) > + dev_err(mbox->dev, "Got error IRQ!\n"); > + > + writel_relaxed(mask, mbox->mbox_base + MAILBOX_REG_IS); one more empty line here. > + return IRQ_HANDLED; > +} > + > +static int xilinx_mbox_startup(struct mbox_chan *chan) > +{ > + int ret; > + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); > + > + if (mbox->intr_mode) { look below > + ret = request_irq(mbox->irq, xilinx_mbox_interrupt, 0, > + dev_name(mbox->dev), chan); > + if (unlikely(ret)) { > + dev_err(mbox->dev, > + "failed to register mailbox interrupt:%d\n", > + ret); > + mbox->intr_mode = false; > + goto polling; /* use polling if failed */ > + } > + > + xilinx_mbox_rx_intmask(mbox, true); Are you also setting up polling timer for interrupt mode? Or here should be return? > + } > + > +polling: > + /* setup polling timer */ > + setup_timer(&mbox->rxpoll_timer, xilinx_mbox_poll_rx, > + (unsigned long)chan); > + mod_timer(&mbox->rxpoll_timer, > + jiffies + msecs_to_jiffies(MBOX_POLLING_MS)); > + > + return 0; > +} > + > +static int xilinx_mbox_send_data(struct mbox_chan *chan, void *data) > +{ > + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); > + u32 *udata = (u32 *)data; > + > + if (!mbox || !data) > + return -EINVAL; > + > + if (xilinx_mbox_full(mbox)) > + return -EBUSY; > + > + /* enable interrupt before send */ > + if (mbox->intr_mode) > + xilinx_mbox_tx_intmask(mbox, true); > + > + writel_relaxed(*udata, mbox->mbox_base + MAILBOX_REG_WRDATA); > + > + return 0; > +} > + > +static bool xilinx_mbox_last_tx_done(struct mbox_chan *chan) > +{ > + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); > + > + /* return false if mailbox is full */ > + return xilinx_mbox_full(mbox) ? false : true; > +} > + > +static bool xilinx_mbox_peek_data(struct mbox_chan *chan) > +{ > + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); > + > + return xilinx_mbox_pending(mbox) ? true : false; > +} > + > +static void xilinx_mbox_shutdown(struct mbox_chan *chan) > +{ > + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); > + > + if (mbox->intr_mode) { > + /* unmask all interrupt masks */ > + writel_relaxed(~0, mbox->mbox_base + MAILBOX_REG_IE); > + free_irq(mbox->irq, chan); > + } else > + del_timer_sync(&mbox->rxpoll_timer); Also {} around else part. > +} > + > +static struct mbox_chan_ops xilinx_mbox_ops = { > + .send_data = xilinx_mbox_send_data, > + .startup = xilinx_mbox_startup, > + .shutdown = xilinx_mbox_shutdown, > + .last_tx_done = xilinx_mbox_last_tx_done, > + .peek_data = xilinx_mbox_peek_data, > +}; > + > +static int xilinx_mbox_probe(struct platform_device *pdev) > +{ > + struct xilinx_mbox *mbox; > + struct resource *regs; > + struct mbox_chan *chans; > + int ret; > + > + mbox = devm_kzalloc(&pdev->dev, sizeof(*mbox), > + GFP_KERNEL); it should fit to one line - no reason for this indentation. > + if (!mbox) > + return -ENOMEM; > + > + /* allocated one channel */ > + chans = devm_kzalloc(&pdev->dev, sizeof(*chans), GFP_KERNEL); > + if (!chans) > + return -ENOMEM; > + > + regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + > + mbox->mbox_base = devm_ioremap_resource(&pdev->dev, regs); > + if (IS_ERR(mbox->mbox_base)) > + return PTR_ERR(mbox->mbox_base); > + > + mbox->irq = platform_get_irq(pdev, 0); > + /* if irq is present, we can use it, otherwise, poll */ > + if (mbox->irq >= 0) > + mbox->intr_mode = true; > + else > + dev_info(&pdev->dev, "IRQ not found, fallback to polling.\n"); Is mbox->intr_mode needed at all? You can simple detect it from mbox->irq anytime. > + > + mbox->dev = &pdev->dev; > + > + /* Hardware supports only one channel. */ > + chans[0].con_priv = mbox; > + mbox->controller.dev = mbox->dev; > + mbox->controller.num_chans = 1; > + mbox->controller.chans = chans; > + mbox->controller.ops = &xilinx_mbox_ops; > + > + if (mbox->intr_mode) { > + mbox->controller.txdone_irq = true; > + } else { > + mbox->controller.txdone_poll = true; > + mbox->controller.txpoll_period = MBOX_POLLING_MS; > + } why is this in the different block? Just put it together with above error message. > + > + ret = mbox_controller_register(&mbox->controller); > + if (ret) { > + dev_err(&pdev->dev, "Register mailbox failed\n"); > + goto err; Just return ret here > + } > + > + platform_set_drvdata(pdev, mbox); > +err: > + return ret; return 0; > +} > + > + > +static int xilinx_mbox_remove(struct platform_device *pdev) > +{ > + struct xilinx_mbox *mbox = platform_get_drvdata(pdev); > + > + if (!mbox) > + return -EINVAL; > + > + mbox_controller_unregister(&mbox->controller); > + > + return 0; > +} > + > +static const struct of_device_id xilinx_mbox_match[] = { > + { .compatible = "xlnx,mailbox-2.1" }, > + { /* Sentinel */ } > +}; > + > +MODULE_DEVICE_TABLE(of, xilinx_mbox_match); > + > +static struct platform_driver xilinx_mbox_driver = { > + .probe = xilinx_mbox_probe, > + .remove = xilinx_mbox_remove, > + .driver = { > + .name = DRIVER_NAME, > + .of_match_table = xilinx_mbox_match, > + }, > +}; > + > +module_platform_driver(xilinx_mbox_driver); > + > +MODULE_LICENSE("GPL v2"); > +MODULE_DESCRIPTION("Xilinx mailbox specific functions"); > +MODULE_AUTHOR("Moritz Fischer <moritz.fischer@ettus.com>"); > +MODULE_ALIAS("platform:xilinx-mailbox"); This is fine but have you tested it as a plain platform driver? Thanks, Michal
diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig index 84b0a2d..e11e4b2 100644 --- a/drivers/mailbox/Kconfig +++ b/drivers/mailbox/Kconfig @@ -60,4 +60,12 @@ config ALTERA_MBOX An implementation of the Altera Mailbox soft core. It is used to send message between processors. Say Y here if you want to use the Altera mailbox support. + +config XILINX_MBOX + tristate "Xilinx Mailbox" + help + An implementation of the Xilinx Mailbox soft core. It is used + to send message between processors. Say Y here if you want to use the + Xilinx mailbox support. + endif diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile index b18201e..d28a028 100644 --- a/drivers/mailbox/Makefile +++ b/drivers/mailbox/Makefile @@ -11,3 +11,5 @@ obj-$(CONFIG_OMAP2PLUS_MBOX) += omap-mailbox.o obj-$(CONFIG_PCC) += pcc.o obj-$(CONFIG_ALTERA_MBOX) += mailbox-altera.o + +obj-$(CONFIG_XILINX_MBOX) += mailbox-xilinx.o diff --git a/drivers/mailbox/mailbox-xilinx.c b/drivers/mailbox/mailbox-xilinx.c new file mode 100644 index 0000000..8d8aa17 --- /dev/null +++ b/drivers/mailbox/mailbox-xilinx.c @@ -0,0 +1,339 @@ +/* + * Copyright (c) 2015, National Instruments Corp. All rights reserved. + * + * Driver for the Xilinx Logicore mailbox IP block + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/device.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/mailbox_controller.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> + +#define DRIVER_NAME "xilinx-mailbox" + +/* register offsets */ +#define MAILBOX_REG_WRDATA 0x00 +#define MAILBOX_REG_RDDATA 0x08 +#define MAILBOX_REG_STATUS 0x10 +#define MAILBOX_REG_ERROR 0x14 +#define MAILBOX_REG_SIT 0x18 +#define MAILBOX_REG_RIT 0x1c +#define MAILBOX_REG_IS 0x20 +#define MAILBOX_REG_IE 0x24 +#define MAILBOX_REG_IP 0x28 + +/* status register */ +#define STS_RTA BIT(3) +#define STS_STA BIT(2) +#define STS_FULL BIT(1) +#define STS_EMPTY BIT(0) + +/* error register */ +#define ERR_FULL BIT(1) +#define ERR_EMPTY BIT(0) + +/* mailbox interrupt status register */ +#define INT_STATUS_ERR BIT(2) +#define INT_STATUS_RTI BIT(1) +#define INT_STATUS_STI BIT(0) + +/* mailbox interrupt enable register */ +#define INT_ENABLE_ERR BIT(2) +#define INT_ENABLE_RTI BIT(1) +#define INT_ENABLE_STI BIT(0) + +#define MBOX_POLLING_MS 5 /* polling interval 5ms */ + +struct xilinx_mbox { + bool intr_mode; + int irq; + void __iomem *mbox_base; + struct device *dev; + struct mbox_controller controller; + + /* if the controller supports only RX polling mode */ + struct timer_list rxpoll_timer; +}; + +static struct xilinx_mbox *mbox_chan_to_xilinx_mbox(struct mbox_chan *chan) +{ + if (!chan || !chan->con_priv) + return NULL; + + return (struct xilinx_mbox *)chan->con_priv; +} + +static inline int xilinx_mbox_full(struct xilinx_mbox *mbox) +{ + u32 status; + + status = readl_relaxed(mbox->mbox_base + MAILBOX_REG_STATUS); + return status & STS_FULL; +} + +static inline int xilinx_mbox_pending(struct xilinx_mbox *mbox) +{ + u32 status; + + status = readl_relaxed(mbox->mbox_base + MAILBOX_REG_STATUS); + return !(status & STS_EMPTY); +} + +static void xilinx_mbox_rx_intmask(struct xilinx_mbox *mbox, bool enable) +{ + u32 mask; + + mask = readl_relaxed(mbox->mbox_base + MAILBOX_REG_IE); + if (enable) + mask |= INT_ENABLE_RTI; + else + mask &= ~INT_ENABLE_RTI; + writel_relaxed(mask, mbox->mbox_base + MAILBOX_REG_IE); +} + +static void xilinx_mbox_tx_intmask(struct xilinx_mbox *mbox, bool enable) +{ + u32 mask; + + mask = readl_relaxed(mbox->mbox_base + MAILBOX_REG_IE); + if (enable) + mask |= INT_ENABLE_STI; + else + mask &= ~INT_ENABLE_STI; + writel_relaxed(mask, mbox->mbox_base + MAILBOX_REG_IE); +} + +static void xilinx_mbox_rx_data(struct mbox_chan *chan) +{ + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); + u32 data; + + if (xilinx_mbox_pending(mbox)) { + data = readl_relaxed(mbox->mbox_base + MAILBOX_REG_RDDATA); + mbox_chan_received_data(chan, (void *)data); + } +} + +static void xilinx_mbox_poll_rx(unsigned long data) +{ + struct mbox_chan *chan = (struct mbox_chan *)data; + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); + + xilinx_mbox_rx_data(chan); + + mod_timer(&mbox->rxpoll_timer, + jiffies + msecs_to_jiffies(MBOX_POLLING_MS)); +} + +static irqreturn_t xilinx_mbox_interrupt(int irq, void *p) +{ + u32 mask; + struct mbox_chan *chan = (struct mbox_chan *)p; + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); + + mask = readl_relaxed(mbox->mbox_base + MAILBOX_REG_IS); + if (mask & INT_STATUS_RTI) + xilinx_mbox_rx_data(chan); + + /* mask irqs *before* notifying done, require tx_block=true */ + if (mask & INT_STATUS_STI) { + xilinx_mbox_tx_intmask(mbox, false); + mbox_chan_txdone(chan, 0); + } + + if (mask & INT_STATUS_ERR) + dev_err(mbox->dev, "Got error IRQ!\n"); + + writel_relaxed(mask, mbox->mbox_base + MAILBOX_REG_IS); + return IRQ_HANDLED; +} + +static int xilinx_mbox_startup(struct mbox_chan *chan) +{ + int ret; + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); + + if (mbox->intr_mode) { + ret = request_irq(mbox->irq, xilinx_mbox_interrupt, 0, + dev_name(mbox->dev), chan); + if (unlikely(ret)) { + dev_err(mbox->dev, + "failed to register mailbox interrupt:%d\n", + ret); + mbox->intr_mode = false; + goto polling; /* use polling if failed */ + } + + xilinx_mbox_rx_intmask(mbox, true); + } + +polling: + /* setup polling timer */ + setup_timer(&mbox->rxpoll_timer, xilinx_mbox_poll_rx, + (unsigned long)chan); + mod_timer(&mbox->rxpoll_timer, + jiffies + msecs_to_jiffies(MBOX_POLLING_MS)); + + return 0; +} + +static int xilinx_mbox_send_data(struct mbox_chan *chan, void *data) +{ + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); + u32 *udata = (u32 *)data; + + if (!mbox || !data) + return -EINVAL; + + if (xilinx_mbox_full(mbox)) + return -EBUSY; + + /* enable interrupt before send */ + if (mbox->intr_mode) + xilinx_mbox_tx_intmask(mbox, true); + + writel_relaxed(*udata, mbox->mbox_base + MAILBOX_REG_WRDATA); + + return 0; +} + +static bool xilinx_mbox_last_tx_done(struct mbox_chan *chan) +{ + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); + + /* return false if mailbox is full */ + return xilinx_mbox_full(mbox) ? false : true; +} + +static bool xilinx_mbox_peek_data(struct mbox_chan *chan) +{ + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); + + return xilinx_mbox_pending(mbox) ? true : false; +} + +static void xilinx_mbox_shutdown(struct mbox_chan *chan) +{ + struct xilinx_mbox *mbox = mbox_chan_to_xilinx_mbox(chan); + + if (mbox->intr_mode) { + /* unmask all interrupt masks */ + writel_relaxed(~0, mbox->mbox_base + MAILBOX_REG_IE); + free_irq(mbox->irq, chan); + } else + del_timer_sync(&mbox->rxpoll_timer); +} + +static struct mbox_chan_ops xilinx_mbox_ops = { + .send_data = xilinx_mbox_send_data, + .startup = xilinx_mbox_startup, + .shutdown = xilinx_mbox_shutdown, + .last_tx_done = xilinx_mbox_last_tx_done, + .peek_data = xilinx_mbox_peek_data, +}; + +static int xilinx_mbox_probe(struct platform_device *pdev) +{ + struct xilinx_mbox *mbox; + struct resource *regs; + struct mbox_chan *chans; + int ret; + + mbox = devm_kzalloc(&pdev->dev, sizeof(*mbox), + GFP_KERNEL); + if (!mbox) + return -ENOMEM; + + /* allocated one channel */ + chans = devm_kzalloc(&pdev->dev, sizeof(*chans), GFP_KERNEL); + if (!chans) + return -ENOMEM; + + regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); + + mbox->mbox_base = devm_ioremap_resource(&pdev->dev, regs); + if (IS_ERR(mbox->mbox_base)) + return PTR_ERR(mbox->mbox_base); + + mbox->irq = platform_get_irq(pdev, 0); + /* if irq is present, we can use it, otherwise, poll */ + if (mbox->irq >= 0) + mbox->intr_mode = true; + else + dev_info(&pdev->dev, "IRQ not found, fallback to polling.\n"); + + mbox->dev = &pdev->dev; + + /* Hardware supports only one channel. */ + chans[0].con_priv = mbox; + mbox->controller.dev = mbox->dev; + mbox->controller.num_chans = 1; + mbox->controller.chans = chans; + mbox->controller.ops = &xilinx_mbox_ops; + + if (mbox->intr_mode) { + mbox->controller.txdone_irq = true; + } else { + mbox->controller.txdone_poll = true; + mbox->controller.txpoll_period = MBOX_POLLING_MS; + } + + ret = mbox_controller_register(&mbox->controller); + if (ret) { + dev_err(&pdev->dev, "Register mailbox failed\n"); + goto err; + } + + platform_set_drvdata(pdev, mbox); +err: + return ret; +} + + +static int xilinx_mbox_remove(struct platform_device *pdev) +{ + struct xilinx_mbox *mbox = platform_get_drvdata(pdev); + + if (!mbox) + return -EINVAL; + + mbox_controller_unregister(&mbox->controller); + + return 0; +} + +static const struct of_device_id xilinx_mbox_match[] = { + { .compatible = "xlnx,mailbox-2.1" }, + { /* Sentinel */ } +}; + +MODULE_DEVICE_TABLE(of, xilinx_mbox_match); + +static struct platform_driver xilinx_mbox_driver = { + .probe = xilinx_mbox_probe, + .remove = xilinx_mbox_remove, + .driver = { + .name = DRIVER_NAME, + .of_match_table = xilinx_mbox_match, + }, +}; + +module_platform_driver(xilinx_mbox_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("Xilinx mailbox specific functions"); +MODULE_AUTHOR("Moritz Fischer <moritz.fischer@ettus.com>"); +MODULE_ALIAS("platform:xilinx-mailbox");
The Xilinx LogiCORE IP mailbox is a FPGA core that allows for interprocessor communication via AXI4 memory mapped / AXI4 stream interfaces. It is single channel per core and allows for transmit and receive. Signed-off-by: Moritz Fischer <moritz.fischer@ettus.com> --- drivers/mailbox/Kconfig | 8 + drivers/mailbox/Makefile | 2 + drivers/mailbox/mailbox-xilinx.c | 339 ++++++++++++++++++++++++++++++++++ 3 files changed, 349 insertions(+)