firmware: raspberrypi: Introduce vl805 init routine

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.

Link: https://lore.kernel.org/r/20200505161318.26200-3-nsaenzjulienne@suse.de
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Rob Herring <robh@kernel.org>
This commit is contained in:
Nicolas Saenz Julienne 2020-05-05 18:13:15 +02:00 committed by Lorenzo Pieralisi
parent ca91ddef2e
commit fbbc5ff3f7
2 changed files with 68 additions and 0 deletions

View File

@ -12,6 +12,8 @@
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <soc/bcm2835/raspberrypi-firmware.h>
#define MBOX_MSG(chan, data28) (((data28) & ~0xf) | ((chan) & 0xf))
@ -19,6 +21,8 @@
#define MBOX_DATA28(msg) ((msg) & ~0xf)
#define MBOX_CHAN_PROPERTY 8
#define VL805_PCI_CONFIG_VERSION_OFFSET 0x50
static struct platform_device *rpi_hwmon;
static struct platform_device *rpi_clk;
@ -286,6 +290,63 @@ struct rpi_firmware *rpi_firmware_get(struct device_node *firmware_node)
}
EXPORT_SYMBOL_GPL(rpi_firmware_get);
/*
* 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. This function triggers the aforementioned
* process.
*/
int rpi_firmware_init_vl805(struct pci_dev *pdev)
{
struct device_node *fw_np;
struct rpi_firmware *fw;
u32 dev_addr, version;
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 -ENODEV;
/*
* Make sure we don't trigger a firmware load unnecessarily.
*
* If something went wrong with PCI, this whole exercise would be
* futile as VideoCore expects from us a configured PCI bus. Just take
* the faulty version (likely ~0) and let xHCI's registration fail
* further down the line.
*/
pci_read_config_dword(pdev, VL805_PCI_CONFIG_VERSION_OFFSET, &version);
if (version)
goto exit;
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;
/* Wait for vl805 to startup */
usleep_range(200, 1000);
pci_read_config_dword(pdev, VL805_PCI_CONFIG_VERSION_OFFSET,
&version);
exit:
pci_info(pdev, "VL805 firmware version %08x\n", version);
return 0;
}
EXPORT_SYMBOL_GPL(rpi_firmware_init_vl805);
static const struct of_device_id rpi_firmware_of_match[] = {
{ .compatible = "raspberrypi,bcm2835-firmware", },
{},

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@ -10,6 +10,7 @@
#include <linux/of_device.h>
struct rpi_firmware;
struct pci_dev;
enum rpi_firmware_property_status {
RPI_FIRMWARE_STATUS_REQUEST = 0,
@ -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 inline int rpi_firmware_init_vl805(struct pci_dev *pdev)
{
return 0;
}
#endif
#endif /* __SOC_RASPBERRY_FIRMWARE_H__ */