[PATCH v2 0/4] Raspberry Pi 4 VL805 firmware load support

[PATCH v2 0/4] Raspberry Pi 4 VL805 firmware load support

[Nicolas Saenz Julienne]

On the Raspberry Pi 4, after a PCI reset, VL805's firmware may either be
loaded directly from an EEPROM or, if not present, by the SoC's
VideCore. This series adds support for the later.

Note that there are a set of constraints we have to consider (some of
them I missed on v1):
 - We need to make sure the VideoCore firmware interface is up and
   running before running the VL805 firmware load call.

 - There is no way to discern RPi4's VL805 chip from other platforms',
   so we need the firmware load to happen *before* running
   quirk_usb_handoff_xhci(). Failure to do so results in an unwarranted
   5 second wait while the fixup code polls xHC's unexisting state.

As per Stefan Wahren's comments I tested the behaviour on outdated
firmware. Boards dependent on this will not boot if firmware is not
up-to-date. Older boards with outdated firmware will fail to execute the
VideoCore firmware call, but xHCI will perform reliably. I added a
warning printout in case of failure.

I'm aware that Florian Fianelli noted on the previous revision that
waiting on the VideoCore firmware interface during PCIe's probe is far
from ideal. But this was before taking into account the second
constraint mentioned above. Impact on non RPi4 boards is minimal.

---

Changes since v1:
 - Split things into their own patches
 - Wait for mailbox interface in pcie-brcmstb
 - Move firmware load code into RPi4 platform code
 - Move firmware load to usb/pci-quirks.c
 - Fix behaviour on outdated firmware

Nicolas Saenz Julienne (4):
  soc: bcm2835: Sync xHCI reset firmware property with downstream
  firmware: raspberrypi: Introduce vl805 init routine
  PCI: brcmstb: Wait for Raspberry Pi's firmware when present
  USB: pci-quirks: Add Raspberry Pi 4 quirk

 drivers/firmware/raspberrypi.c             | 37 ++++++++++++++++++++++
 drivers/pci/controller/pcie-brcmstb.c      | 15 +++++++++
 drivers/usb/host/pci-quirks.c              | 18 +++++++++++
 include/soc/bcm2835/raspberrypi-firmware.h |  9 +++++-
 4 files changed, 78 insertions(+), 1 deletion(-)

-- 
2.25.0

[PATCH v2 1/4] soc: bcm2835: Sync xHCI reset firmware property with downstream

[Nicolas Saenz Julienne]

The property is needed in order to trigger VL805's firmware load.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
---

Note that there is a gap between the property introduced and the previous
one. This is also the case downstream.

Changes since v1:
 - move into own patch

 include/soc/bcm2835/raspberrypi-firmware.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/soc/bcm2835/raspberrypi-firmware.h b/include/soc/bcm2835/raspberrypi-firmware.h
index 7800e12ee042..cc9cdbc66403 100644
--- a/include/soc/bcm2835/raspberrypi-firmware.h
+++ b/include/soc/bcm2835/raspberrypi-firmware.h
@@ -90,7 +90,7 @@ enum rpi_firmware_property_tag {
 	RPI_FIRMWARE_SET_PERIPH_REG =                         0x00038045,
 	RPI_FIRMWARE_GET_POE_HAT_VAL =                        0x00030049,
 	RPI_FIRMWARE_SET_POE_HAT_VAL =                        0x00030050,
-
+	RPI_FIRMWARE_NOTIFY_XHCI_RESET =                      0x00030058,
 
 	/* Dispmanx TAGS */
 	RPI_FIRMWARE_FRAMEBUFFER_ALLOCATE =                   0x00040001,
-- 
2.25.0

[PATCH v2 2/4] firmware: raspberrypi: Introduce vl805 init routine

[Nicolas Saenz Julienne]

On the Raspberry Pi 4, after a PCI reset, VL805's firmware may either be
loaded directly from an EEPROM or, if not present, by the SoC's
VideCore. The function informs VideCore that VL805 was just reset, or
requests for a probe defer.

Based on Tim Gover's downstream implementation.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
---

Changes since v1:
 - Moved into own commit and firmware/raspberrypi.c

 drivers/firmware/raspberrypi.c             | 37 ++++++++++++++++++++++
 include/soc/bcm2835/raspberrypi-firmware.h |  7 ++++
 2 files changed, 44 insertions(+)

diff --git a/drivers/firmware/raspberrypi.c b/drivers/firmware/raspberrypi.c
index da26a584dca0..cc0563029805 100644
--- a/drivers/firmware/raspberrypi.c
+++ b/drivers/firmware/raspberrypi.c
@@ -286,6 +286,43 @@ struct rpi_firmware *rpi_firmware_get(struct device_node *firmware_node)
 }
 EXPORT_SYMBOL_GPL(rpi_firmware_get);
 
+/*
+ * On the Raspberry Pi 4, after a PCI reset, VL805's firmware may either be
+ * loaded directly from an EEPROM or, if not present, by the SoC's VideCore.
+ * Inform VideCore that VL805 was just reset, or defer xhci's probe if not yet
+ * joinable trough the mailbox interface.
+ */
+int rpi_firmware_init_vl805(struct pci_dev *pdev)
+{
+	struct device_node *fw_np;
+	struct rpi_firmware *fw;
+	u32 dev_addr;
+	int ret;
+
+	fw_np = of_find_compatible_node(NULL, NULL,
+					"raspberrypi,bcm2835-firmware");
+	if (!fw_np)
+		return 0;
+
+	fw = rpi_firmware_get(fw_np);
+	of_node_put(fw_np);
+	if (!fw)
+		return -EPROBE_DEFER;
+
+	dev_addr = pdev->bus->number << 20 | PCI_SLOT(pdev->devfn) << 15 |
+		   PCI_FUNC(pdev->devfn) << 12;
+
+	ret = rpi_firmware_property(fw, RPI_FIRMWARE_NOTIFY_XHCI_RESET,
+				    &dev_addr, sizeof(dev_addr));
+	if (ret)
+		return ret;
+
+	dev_dbg(&pdev->dev, "loaded Raspberry Pi's VL805 firmware\n");
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(rpi_firmware_init_vl805);
+
 static const struct of_device_id rpi_firmware_of_match[] = {
 	{ .compatible = "raspberrypi,bcm2835-firmware", },
 	{},
diff --git a/include/soc/bcm2835/raspberrypi-firmware.h b/include/soc/bcm2835/raspberrypi-firmware.h
index cc9cdbc66403..a37c3a461d2a 100644
--- a/include/soc/bcm2835/raspberrypi-firmware.h
+++ b/include/soc/bcm2835/raspberrypi-firmware.h
@@ -8,6 +8,7 @@
 
 #include <linux/types.h>
 #include <linux/of_device.h>
+#include <linux/pci.h>
 
 struct rpi_firmware;
 
@@ -141,6 +142,7 @@ int rpi_firmware_property(struct rpi_firmware *fw,
 int rpi_firmware_property_list(struct rpi_firmware *fw,
 			       void *data, size_t tag_size);
 struct rpi_firmware *rpi_firmware_get(struct device_node *firmware_node);
+int rpi_firmware_init_vl805(struct pci_dev *pdev);
 #else
 static inline int rpi_firmware_property(struct rpi_firmware *fw, u32 tag,
 					void *data, size_t len)
@@ -158,6 +160,11 @@ static inline struct rpi_firmware *rpi_firmware_get(struct device_node *firmware
 {
 	return NULL;
 }
+
+static int rpi_firmware_init_vl805(struct pci_dev *pdev)
+{
+	return 0;
+}
 #endif
 
 #endif /* __SOC_RASPBERRY_FIRMWARE_H__ */
-- 
2.25.0

[PATCH v2 3/4] PCI: brcmstb: Wait for Raspberry Pi's firmware when present

[Nicolas Saenz Julienne]

xHCI's PCI fixup, run at the end of pcie-brcmstb's probe, depends on
RPi4's VideoCore firmware interface to be up and running. It's possible
for both initializations to race, so make sure it's available prior
starting.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
---
 drivers/pci/controller/pcie-brcmstb.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/drivers/pci/controller/pcie-brcmstb.c b/drivers/pci/controller/pcie-brcmstb.c
index d20aabc26273..9600052f768c 100644
--- a/drivers/pci/controller/pcie-brcmstb.c
+++ b/drivers/pci/controller/pcie-brcmstb.c
@@ -28,6 +28,8 @@
 #include <linux/string.h>
 #include <linux/types.h>
 
+#include <soc/bcm2835/raspberrypi-firmware.h>
+
 #include "../pci.h"
 
 /* BRCM_PCIE_CAP_REGS - Offset for the mandatory capability config regs */
@@ -917,11 +919,24 @@ static int brcm_pcie_probe(struct platform_device *pdev)
 {
 	struct device_node *np = pdev->dev.of_node, *msi_np;
 	struct pci_host_bridge *bridge;
+	struct device_node *fw_np;
 	struct brcm_pcie *pcie;
 	struct pci_bus *child;
 	struct resource *res;
 	int ret;
 
+	/*
+	 * We have to wait for the Raspberry Pi's firmware interface to be up
+	 * as some PCI fixups depend on it.
+	 */
+	fw_np = of_find_compatible_node(NULL, NULL,
+					"raspberrypi,bcm2835-firmware");
+	if (fw_np && !rpi_firmware_get(fw_np)) {
+		of_node_put(fw_np);
+		return -EPROBE_DEFER;
+	}
+	of_node_put(fw_np);
+
 	bridge = devm_pci_alloc_host_bridge(&pdev->dev, sizeof(*pcie));
 	if (!bridge)
 		return -ENOMEM;
-- 
2.25.0

[PATCH v2 4/4] USB: pci-quirks: Add Raspberry Pi 4 quirk

[Nicolas Saenz Julienne]

On the Raspberry Pi 4, after a PCI reset, VL805's firmware may either be
loaded directly from an EEPROM or, if not present, by the SoC's
VideCore. Inform VideCore that VL805 was just reset.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
---
 drivers/usb/host/pci-quirks.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/drivers/usb/host/pci-quirks.c b/drivers/usb/host/pci-quirks.c
index beb2efa71341..aee2eaa3f0e1 100644
--- a/drivers/usb/host/pci-quirks.c
+++ b/drivers/usb/host/pci-quirks.c
@@ -16,6 +16,9 @@
 #include <linux/export.h>
 #include <linux/acpi.h>
 #include <linux/dmi.h>
+
+#include <soc/bcm2835/raspberrypi-firmware.h>
+
 #include "pci-quirks.h"
 #include "xhci-ext-caps.h"
 
@@ -1243,11 +1246,26 @@ static void quirk_usb_handoff_xhci(struct pci_dev *pdev)
 
 static void quirk_usb_early_handoff(struct pci_dev *pdev)
 {
+	int ret;
+
 	/* Skip Netlogic mips SoC's internal PCI USB controller.
 	 * This device does not need/support EHCI/OHCI handoff
 	 */
 	if (pdev->vendor == 0x184e)	/* vendor Netlogic */
 		return;
+
+	if (pdev->vendor == PCI_VENDOR_ID_VIA && pdev->device == 0x3483) {
+		ret = rpi_firmware_init_vl805(pdev);
+		if (ret)
+			/*
+			 * Firmware might be outdated, or else, something
+			 * failed, keep going and hope for the best.
+			 */
+			dev_warn(&pdev->dev,
+				 "Failed to load VL805's firmware: %d\n",
+				 ret);
+	}
+
 	if (pdev->class != PCI_CLASS_SERIAL_USB_UHCI &&
 			pdev->class != PCI_CLASS_SERIAL_USB_OHCI &&
 			pdev->class != PCI_CLASS_SERIAL_USB_EHCI &&
-- 
2.25.0

Re: [PATCH v2 2/4] firmware: raspberrypi: Introduce vl805 init routine

[Florian Fainelli]

On 2/19/20 4:39 AM, Nicolas Saenz Julienne wrote:
> On the Raspberry Pi 4, after a PCI reset, VL805's firmware may either be
> loaded directly from an EEPROM or, if not present, by the SoC's
> VideCore. The function informs VideCore that VL805 was just reset, or
> requests for a probe defer.
> 
> Based on Tim Gover's downstream implementation.
> 
> Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
> ---

[snip]


> diff --git a/include/soc/bcm2835/raspberrypi-firmware.h b/include/soc/bcm2835/raspberrypi-firmware.h
> index cc9cdbc66403..a37c3a461d2a 100644
> --- a/include/soc/bcm2835/raspberrypi-firmware.h
> +++ b/include/soc/bcm2835/raspberrypi-firmware.h
> @@ -8,6 +8,7 @@
>  
>  #include <linux/types.h>
>  #include <linux/of_device.h>
> +#include <linux/pci.h>

I would move this inclusion where we need it, which is in
drivers/firmware/raspberrypi.c and only provide a forward declaration
here (avoids needless rebuilds).

With that:

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian

Re: [PATCH v2 1/4] soc: bcm2835: Sync xHCI reset firmware property with downstream

[Florian Fainelli]

On 2/19/20 4:39 AM, Nicolas Saenz Julienne wrote:
> The property is needed in order to trigger VL805's firmware load.
> 
> Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
-- 
Florian

Re: [PATCH v2 3/4] PCI: brcmstb: Wait for Raspberry Pi's firmware when present

[Florian Fainelli]

On 2/19/20 4:39 AM, Nicolas Saenz Julienne wrote:
> xHCI's PCI fixup, run at the end of pcie-brcmstb's probe, depends on
> RPi4's VideoCore firmware interface to be up and running. It's possible
> for both initializations to race, so make sure it's available prior
> starting.
> 
> Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>

Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>

It does not look like there is something making sure that
CONFIG_RASPBERRYPI_FIRMWARE is being selected or depended on, should we
have a "default XHCI_PCI" added to drivers/firmware/Kconfig?
-- 
Florian

Re: [PATCH v2 2/4] firmware: raspberrypi: Introduce vl805 init routine

[Nicolas Saenz Julienne]

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On Wed, 2020-02-19 at 11:13 -0800, Florian Fainelli wrote:
> On 2/19/20 4:39 AM, Nicolas Saenz Julienne wrote:
> > On the Raspberry Pi 4, after a PCI reset, VL805's firmware may either be
> > loaded directly from an EEPROM or, if not present, by the SoC's
> > VideCore. The function informs VideCore that VL805 was just reset, or
> > requests for a probe defer.
> > 
> > Based on Tim Gover's downstream implementation.
> > 
> > Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
> > ---
> 
> [snip]
> 
> 
> > diff --git a/include/soc/bcm2835/raspberrypi-firmware.h
> > b/include/soc/bcm2835/raspberrypi-firmware.h
> > index cc9cdbc66403..a37c3a461d2a 100644
> > --- a/include/soc/bcm2835/raspberrypi-firmware.h
> > +++ b/include/soc/bcm2835/raspberrypi-firmware.h
> > @@ -8,6 +8,7 @@
> >  
> >  #include <linux/types.h>
> >  #include <linux/of_device.h>
> > +#include <linux/pci.h>
> 
> I would move this inclusion where we need it, which is in
> drivers/firmware/raspberrypi.c and only provide a forward declaration
> here (avoids needless rebuilds).

Noted


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Re: [PATCH v2 3/4] PCI: brcmstb: Wait for Raspberry Pi's firmware when present

[Nicolas Saenz Julienne]

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On Wed, 2020-02-19 at 11:21 -0800, Florian Fainelli wrote:
> On 2/19/20 4:39 AM, Nicolas Saenz Julienne wrote:
> > xHCI's PCI fixup, run at the end of pcie-brcmstb's probe, depends on
> > RPi4's VideoCore firmware interface to be up and running. It's possible
> > for both initializations to race, so make sure it's available prior
> > starting.
> > 
> > Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
> 
> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
> 
> It does not look like there is something making sure that
> CONFIG_RASPBERRYPI_FIRMWARE is being selected or depended on, should we
> have a "default XHCI_PCI" added to drivers/firmware/Kconfig?

I think having that would enable the firmware interface for all XHCI_PCI users,
which isn't ideal. The firmware call has stubs for the case the firmware
interace isn't compiled, so no problem there. Ultimately we want to enable
CONFIG_RASPBERRYPI_FIRMWARE only when the built image targets the RPi4
(reglardless of being arm64/arm32). But I don't think that's feasible.

Regards,
Nicolas


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Re: [PATCH v2 3/4] PCI: brcmstb: Wait for Raspberry Pi's firmware when present

[Florian Fainelli]

On 2/20/2020 10:14 AM, Nicolas Saenz Julienne wrote:
> On Wed, 2020-02-19 at 11:21 -0800, Florian Fainelli wrote:
>> On 2/19/20 4:39 AM, Nicolas Saenz Julienne wrote:
>>> xHCI's PCI fixup, run at the end of pcie-brcmstb's probe, depends on
>>> RPi4's VideoCore firmware interface to be up and running. It's possible
>>> for both initializations to race, so make sure it's available prior
>>> starting.
>>>
>>> Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
>>
>> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
>>
>> It does not look like there is something making sure that
>> CONFIG_RASPBERRYPI_FIRMWARE is being selected or depended on, should we
>> have a "default XHCI_PCI" added to drivers/firmware/Kconfig?
> 
> I think having that would enable the firmware interface for all XHCI_PCI users,
> which isn't ideal. The firmware call has stubs for the case the firmware
> interace isn't compiled, so no problem there. Ultimately we want to enable
> CONFIG_RASPBERRYPI_FIRMWARE only when the built image targets the RPi4
> (reglardless of being arm64/arm32). But I don't think that's feasible.

It would enable the driver, which is only functional if the matching
Device Tree node is present, that seems like a reasonable price to pay
for a multiplatform kernel. After all, this is a functional dependency
for the Pi4.
-- 
Florian