| Message ID | 20200609175003.19793-3-nsaenzjulienne@suse.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Raspberry Pi 4 USB firmware initialization rework | expand |
On 6/9/2020 10:49 AM, Nicolas Saenz Julienne wrote: > Raspberry Pi 4's co-processor controls some of the board's HW > initialization process, but it's up to Linux to trigger it when > relevant. Introduce a reset controller capable of interfacing with > RPi4's co-processor that models these firmware initialization routines as > reset lines. > > Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> > > --- > > Changes since v1: > - Make the whole driver less USB centric as per Florian's comments > > drivers/reset/Kconfig | 11 +++ > drivers/reset/Makefile | 1 + > drivers/reset/reset-raspberrypi.c | 126 ++++++++++++++++++++++++++++++ > 3 files changed, 138 insertions(+) > create mode 100644 drivers/reset/reset-raspberrypi.c > > diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig > index d9efbfd29646..97e848740e13 100644 > --- a/drivers/reset/Kconfig > +++ b/drivers/reset/Kconfig > @@ -140,6 +140,17 @@ config RESET_QCOM_PDC > to control reset signals provided by PDC for Modem, Compute, > Display, GPU, Debug, AOP, Sensors, Audio, SP and APPS. > > +config RESET_RASPBERRYPI > + tristate "Raspberry Pi 4 Firmware Reset Driver" > + depends on RASPBERRYPI_FIRMWARE || (RASPBERRYPI_FIRMWARE=n && COMPILE_TEST) > + default USB_XHCI_PCI > + help > + Raspberry Pi 4's co-processor controls some of the board's HW > + initialization process, but it's up to Linux to trigger it when > + relevant. This driver provides a reset controller capable of > + interfacing with RPi4's co-processor and model these firmware > + initialization routines as reset lines. > + > config RESET_SCMI > tristate "Reset driver controlled via ARM SCMI interface" > depends on ARM_SCMI_PROTOCOL || COMPILE_TEST > diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile > index 249ed357c997..16947610cc3b 100644 > --- a/drivers/reset/Makefile > +++ b/drivers/reset/Makefile > @@ -21,6 +21,7 @@ obj-$(CONFIG_RESET_OXNAS) += reset-oxnas.o > obj-$(CONFIG_RESET_PISTACHIO) += reset-pistachio.o > obj-$(CONFIG_RESET_QCOM_AOSS) += reset-qcom-aoss.o > obj-$(CONFIG_RESET_QCOM_PDC) += reset-qcom-pdc.o > +obj-$(CONFIG_RESET_RASPBERRYPI) += reset-raspberrypi.o > obj-$(CONFIG_RESET_SCMI) += reset-scmi.o > obj-$(CONFIG_RESET_SIMPLE) += reset-simple.o > obj-$(CONFIG_RESET_STM32MP157) += reset-stm32mp1.o > diff --git a/drivers/reset/reset-raspberrypi.c b/drivers/reset/reset-raspberrypi.c > new file mode 100644 > index 000000000000..5fc8c6319a20 > --- /dev/null > +++ b/drivers/reset/reset-raspberrypi.c > @@ -0,0 +1,126 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Raspberry Pi 4 firmware reset driver > + * > + * Copyright (C) 2020 Nicolas Saenz Julienne <nsaenzjulienne@suse.de> > + */ > +#include <linux/delay.h> > +#include <linux/device.h> > +#include <linux/module.h> > +#include <linux/of.h> > +#include <linux/platform_device.h> > +#include <linux/reset-controller.h> > +#include <soc/bcm2835/raspberrypi-firmware.h> > + > +struct rpi_reset { > + struct reset_controller_dev rcdev; > + struct rpi_firmware *fw; > +}; > + > +enum rpi_reset_ids { > + RASPBERRYPI_FIRMWARE_RESET_ID_USB, You should probably move this to a header file under include/dt-bindings/reset/ in order to ensure that what gets referenced by the DTS is in sync with what the driver knows about. With that: Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
On Tue, 2020-06-09 at 11:14 -0700, Florian Fainelli wrote: > > On 6/9/2020 10:49 AM, Nicolas Saenz Julienne wrote: > > Raspberry Pi 4's co-processor controls some of the board's HW > > initialization process, but it's up to Linux to trigger it when > > relevant. Introduce a reset controller capable of interfacing with > > RPi4's co-processor that models these firmware initialization routines as > > reset lines. > > > > Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> > > > > --- > > > > Changes since v1: > > - Make the whole driver less USB centric as per Florian's comments > > > > drivers/reset/Kconfig | 11 +++ > > drivers/reset/Makefile | 1 + > > drivers/reset/reset-raspberrypi.c | 126 ++++++++++++++++++++++++++++++ > > 3 files changed, 138 insertions(+) > > create mode 100644 drivers/reset/reset-raspberrypi.c > > > > diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig > > index d9efbfd29646..97e848740e13 100644 > > --- a/drivers/reset/Kconfig > > +++ b/drivers/reset/Kconfig > > @@ -140,6 +140,17 @@ config RESET_QCOM_PDC > > to control reset signals provided by PDC for Modem, Compute, > > Display, GPU, Debug, AOP, Sensors, Audio, SP and APPS. > > > > +config RESET_RASPBERRYPI > > + tristate "Raspberry Pi 4 Firmware Reset Driver" > > + depends on RASPBERRYPI_FIRMWARE || (RASPBERRYPI_FIRMWARE=n && > > COMPILE_TEST) > > + default USB_XHCI_PCI > > + help > > + Raspberry Pi 4's co-processor controls some of the board's HW > > + initialization process, but it's up to Linux to trigger it when > > + relevant. This driver provides a reset controller capable of > > + interfacing with RPi4's co-processor and model these firmware > > + initialization routines as reset lines. > > + > > config RESET_SCMI > > tristate "Reset driver controlled via ARM SCMI interface" > > depends on ARM_SCMI_PROTOCOL || COMPILE_TEST > > diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile > > index 249ed357c997..16947610cc3b 100644 > > --- a/drivers/reset/Makefile > > +++ b/drivers/reset/Makefile > > @@ -21,6 +21,7 @@ obj-$(CONFIG_RESET_OXNAS) += reset-oxnas.o > > obj-$(CONFIG_RESET_PISTACHIO) += reset-pistachio.o > > obj-$(CONFIG_RESET_QCOM_AOSS) += reset-qcom-aoss.o > > obj-$(CONFIG_RESET_QCOM_PDC) += reset-qcom-pdc.o > > +obj-$(CONFIG_RESET_RASPBERRYPI) += reset-raspberrypi.o > > obj-$(CONFIG_RESET_SCMI) += reset-scmi.o > > obj-$(CONFIG_RESET_SIMPLE) += reset-simple.o > > obj-$(CONFIG_RESET_STM32MP157) += reset-stm32mp1.o > > diff --git a/drivers/reset/reset-raspberrypi.c b/drivers/reset/reset- > > raspberrypi.c > > new file mode 100644 > > index 000000000000..5fc8c6319a20 > > --- /dev/null > > +++ b/drivers/reset/reset-raspberrypi.c > > @@ -0,0 +1,126 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* > > + * Raspberry Pi 4 firmware reset driver > > + * > > + * Copyright (C) 2020 Nicolas Saenz Julienne <nsaenzjulienne@suse.de> > > + */ > > +#include <linux/delay.h> > > +#include <linux/device.h> > > +#include <linux/module.h> > > +#include <linux/of.h> > > +#include <linux/platform_device.h> > > +#include <linux/reset-controller.h> > > +#include <soc/bcm2835/raspberrypi-firmware.h> > > + > > +struct rpi_reset { > > + struct reset_controller_dev rcdev; > > + struct rpi_firmware *fw; > > +}; > > + > > +enum rpi_reset_ids { > > + RASPBERRYPI_FIRMWARE_RESET_ID_USB, > > You should probably move this to a header file under > include/dt-bindings/reset/ in order to ensure that what gets referenced > by the DTS is in sync with what the driver knows about. > > With that: > > Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Thanks! Will fix that on v3. Regards, Nicolas
diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig index d9efbfd29646..97e848740e13 100644 --- a/drivers/reset/Kconfig +++ b/drivers/reset/Kconfig @@ -140,6 +140,17 @@ config RESET_QCOM_PDC to control reset signals provided by PDC for Modem, Compute, Display, GPU, Debug, AOP, Sensors, Audio, SP and APPS. +config RESET_RASPBERRYPI + tristate "Raspberry Pi 4 Firmware Reset Driver" + depends on RASPBERRYPI_FIRMWARE || (RASPBERRYPI_FIRMWARE=n && COMPILE_TEST) + default USB_XHCI_PCI + help + Raspberry Pi 4's co-processor controls some of the board's HW + initialization process, but it's up to Linux to trigger it when + relevant. This driver provides a reset controller capable of + interfacing with RPi4's co-processor and model these firmware + initialization routines as reset lines. + config RESET_SCMI tristate "Reset driver controlled via ARM SCMI interface" depends on ARM_SCMI_PROTOCOL || COMPILE_TEST diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile index 249ed357c997..16947610cc3b 100644 --- a/drivers/reset/Makefile +++ b/drivers/reset/Makefile @@ -21,6 +21,7 @@ obj-$(CONFIG_RESET_OXNAS) += reset-oxnas.o obj-$(CONFIG_RESET_PISTACHIO) += reset-pistachio.o obj-$(CONFIG_RESET_QCOM_AOSS) += reset-qcom-aoss.o obj-$(CONFIG_RESET_QCOM_PDC) += reset-qcom-pdc.o +obj-$(CONFIG_RESET_RASPBERRYPI) += reset-raspberrypi.o obj-$(CONFIG_RESET_SCMI) += reset-scmi.o obj-$(CONFIG_RESET_SIMPLE) += reset-simple.o obj-$(CONFIG_RESET_STM32MP157) += reset-stm32mp1.o diff --git a/drivers/reset/reset-raspberrypi.c b/drivers/reset/reset-raspberrypi.c new file mode 100644 index 000000000000..5fc8c6319a20 --- /dev/null +++ b/drivers/reset/reset-raspberrypi.c @@ -0,0 +1,126 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Raspberry Pi 4 firmware reset driver + * + * Copyright (C) 2020 Nicolas Saenz Julienne <nsaenzjulienne@suse.de> + */ +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/reset-controller.h> +#include <soc/bcm2835/raspberrypi-firmware.h> + +struct rpi_reset { + struct reset_controller_dev rcdev; + struct rpi_firmware *fw; +}; + +enum rpi_reset_ids { + RASPBERRYPI_FIRMWARE_RESET_ID_USB, + RASPBERRYPI_FIRMWARE_RESET_NUM_IDS +}; + +static inline struct rpi_reset *to_rpi(struct reset_controller_dev *rcdev) +{ + return container_of(rcdev, struct rpi_reset, rcdev); +} + +static int rpi_reset_reset(struct reset_controller_dev *rcdev, unsigned long id) +{ + struct rpi_reset *priv = to_rpi(rcdev); + u32 dev_addr; + int ret; + + switch (id) { + case RASPBERRYPI_FIRMWARE_RESET_ID_USB: + /* + * The Raspberry Pi 4 gets its USB functionality from VL805, a + * PCIe chip that implements xHCI. After a PCI reset, VL805's + * firmware may either be loaded directly from an EEPROM or, if + * not present, by the SoC's co-processor, VideoCore. rpi's + * VideoCore OS contains both the non public firmware load + * logic and the VL805 firmware blob. This triggers the + * aforementioned process. + * + * The pci device address is expected is expected by the + * firmware encoded like this: + * + * PCI_BUS << 20 | PCI_SLOT << 15 | PCI_FUNC << 12 + * + * But since rpi's PCIe is hardwired, we know the address in + * advance. + */ + dev_addr = 0x100000; + ret = rpi_firmware_property(priv->fw, RPI_FIRMWARE_NOTIFY_XHCI_RESET, + &dev_addr, sizeof(dev_addr)); + if (ret) + return ret; + + /* Wait for vl805 to startup */ + usleep_range(200, 1000); + break; + + default: + return -EINVAL; + } + + return 0; +} + +static const struct reset_control_ops rpi_reset_ops = { + .reset = rpi_reset_reset, +}; + +static int rpi_reset_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *fw_node; + struct rpi_firmware *fw; + struct rpi_reset *priv; + + fw_node = of_get_parent(dev->of_node); + if (!fw_node) { + dev_err(dev, "Missing firmware node\n"); + return -ENOENT; + } + + fw = rpi_firmware_get(fw_node); + of_node_put(fw_node); + if (!fw) + return -EPROBE_DEFER; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + dev_set_drvdata(dev, priv); + + priv->fw = fw; + priv->rcdev.owner = THIS_MODULE; + priv->rcdev.nr_resets = RASPBERRYPI_FIRMWARE_RESET_NUM_IDS; + priv->rcdev.ops = &rpi_reset_ops; + priv->rcdev.of_node = dev->of_node; + + return devm_reset_controller_register(dev, &priv->rcdev); +} + +static const struct of_device_id rpi_reset_of_match[] = { + { .compatible = "raspberrypi,firmware-reset" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, rpi_reset_of_match); + +static struct platform_driver rpi_reset_driver = { + .probe = rpi_reset_probe, + .driver = { + .name = "raspberrypi-reset", + .of_match_table = rpi_reset_of_match, + }, +}; +module_platform_driver(rpi_reset_driver); + +MODULE_AUTHOR("Nicolas Saenz Julienne <nsaenzjulienne@suse.de>"); +MODULE_DESCRIPTION("Raspberry Pi 4 firmware reset driver"); +MODULE_LICENSE("GPL");
Raspberry Pi 4's co-processor controls some of the board's HW initialization process, but it's up to Linux to trigger it when relevant. Introduce a reset controller capable of interfacing with RPi4's co-processor that models these firmware initialization routines as reset lines. Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> --- Changes since v1: - Make the whole driver less USB centric as per Florian's comments drivers/reset/Kconfig | 11 +++ drivers/reset/Makefile | 1 + drivers/reset/reset-raspberrypi.c | 126 ++++++++++++++++++++++++++++++ 3 files changed, 138 insertions(+) create mode 100644 drivers/reset/reset-raspberrypi.c