Re: [PATCH v8 2/4] firmware: raspberrypi: Introduce vl805 init routine

Hi Nicolas,

Am 07.05.20 um 23:48 schrieb Rob Herring:

quoted

On Tue,  5 May 2020 18:13:15 +0200, Nicolas Saenz Julienne wrote:

quoted

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. RPi4's VideoCore OS contains both the non public
firmware load logic and the VL805 firmware blob. The function this patch
introduces triggers the aforementioned process.

Signed-off-by: Nicolas Saenz Julienne <redacted>

---

Change since v7:
- Use usleep_delay()
- Add comment about PCI errors
- Don't wait on error
- Typos

Change since v6:
- Add test to avoid loading the firmware when not needed
- Since we have it around, print VL805's firmware version, it'll make
debugging easier in the future
- Correct typos
- Add a clearer view of HW topology in patch description

Changes since v4:
- Inline function definition when RASPBERRYPI_FIRMWARE is not defined

Changes since v1:
- Move include into .c file and add forward declaration to .h

 drivers/firmware/raspberrypi.c             | 61 ++++++++++++++++++++++
 include/soc/bcm2835/raspberrypi-firmware.h |  7 +++
 2 files changed, 68 insertions(+)

Reviewed-by: Rob Herring <robh@kernel.org>

i modified the code a little bit for testing, but also successfully
tested it without my modifications:

diff --git a/drivers/firmware/raspberrypi.c b/drivers/firmware/raspberrypi.c
index 0d1422b..f3f4c2d 100644
--- a/drivers/firmware/raspberrypi.c
+++ b/drivers/firmware/raspberrypi.c

@@ -337,8 +337,10 @@ int rpi_firmware_init_vl805(struct pci_dev *pdev)

         * further down the line.
         */
        pci_read_config_dword(pdev, VL805_PCI_CONFIG_VERSION_OFFSET,
&version);
-       if (version)
-               goto exit;
+       if (version) {
+               pci_info(pdev, "VL805 EEPROM firmware version %08x\n",
version);
+               return 0;
+       }
 
        dev_addr = pdev->bus->number << 20 | PCI_SLOT(pdev->devfn) << 15 |
                   PCI_FUNC(pdev->devfn) << 12;

@@ -353,9 +355,8 @@ int rpi_firmware_init_vl805(struct pci_dev *pdev)

 
        pci_read_config_dword(pdev, VL805_PCI_CONFIG_VERSION_OFFSET,
                              &version);
-exit:
-       pci_info(pdev, "VL805 firmware version %08x\n", version);
 
+       pci_info(pdev, "VL805 RAM firmware version %08x\n", version);
        return 0;
 }
 EXPORT_SYMBOL_GPL(rpi_firmware_init_vl805);

Here are the my results with 3x Raspberry Pi 4:

VL805 EEPROM firmware version 000137ad
VL805 EEPROM firmware version 00013701
VL805 RAM firmware version 000137ad

So the whole patch series is:

Tested-by: Stefan Wahren <redacted>