u-boot/drivers/usb/host/xhci-pci.c
Samuel Holland 70a98caf19 usb: xhci-pci: Move reset logic out of XHCI core
Resetting an XHCI controller inside xhci_register undoes any register
setup performed by the platform driver. And at least on the Allwinner
H6, resetting the XHCI controller also resets the PHY, which prevents
the controller from working. That means the controller must be taken out
of reset before initializing the PHY, which must be done before calling
xhci_register.

The logic in the XHCI core was added to support the Raspberry Pi 4
(although this was not mentioned in the commit log!), which uses the
xhci-pci platform driver. Move the reset logic to the platform driver,
where it belongs, and where it cannot interfere with other platform
drivers.

This also fixes a failure to call reset_free if xhci_register failed.

Fixes: 0b80371b35 ("usb: xhci: Add reset controller support")
Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
2021-09-22 21:29:56 +02:00

125 lines
2.6 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2015, Google, Inc
* Written by Simon Glass <sjg@chromium.org>
* All rights reserved.
*/
#include <common.h>
#include <dm.h>
#include <dm/device_compat.h>
#include <init.h>
#include <log.h>
#include <pci.h>
#include <reset.h>
#include <usb.h>
#include <usb/xhci.h>
struct xhci_pci_plat {
struct reset_ctl reset;
};
static int xhci_pci_init(struct udevice *dev, struct xhci_hccr **ret_hccr,
struct xhci_hcor **ret_hcor)
{
struct xhci_hccr *hccr;
struct xhci_hcor *hcor;
u32 cmd;
hccr = (struct xhci_hccr *)dm_pci_map_bar(dev,
PCI_BASE_ADDRESS_0, PCI_REGION_MEM);
if (!hccr) {
printf("xhci-pci init cannot map PCI mem bar\n");
return -EIO;
}
hcor = (struct xhci_hcor *)((uintptr_t) hccr +
HC_LENGTH(xhci_readl(&hccr->cr_capbase)));
debug("XHCI-PCI init hccr %p and hcor %p hc_length %d\n",
hccr, hcor, (u32)HC_LENGTH(xhci_readl(&hccr->cr_capbase)));
*ret_hccr = hccr;
*ret_hcor = hcor;
/* enable busmaster */
dm_pci_read_config32(dev, PCI_COMMAND, &cmd);
cmd |= PCI_COMMAND_MASTER;
dm_pci_write_config32(dev, PCI_COMMAND, cmd);
return 0;
}
static int xhci_pci_probe(struct udevice *dev)
{
struct xhci_pci_plat *plat = dev_get_plat(dev);
struct xhci_hccr *hccr;
struct xhci_hcor *hcor;
int ret;
ret = reset_get_by_index(dev, 0, &plat->reset);
if (ret && ret != -ENOENT && ret != -ENOTSUPP) {
dev_err(dev, "failed to get reset\n");
return ret;
}
if (reset_valid(&plat->reset)) {
ret = reset_assert(&plat->reset);
if (ret)
goto err_reset;
ret = reset_deassert(&plat->reset);
if (ret)
goto err_reset;
}
ret = xhci_pci_init(dev, &hccr, &hcor);
if (ret)
goto err_reset;
ret = xhci_register(dev, hccr, hcor);
if (ret)
goto err_reset;
return 0;
err_reset:
if (reset_valid(&plat->reset))
reset_free(&plat->reset);
return ret;
}
static int xhci_pci_remove(struct udevice *dev)
{
struct xhci_pci_plat *plat = dev_get_plat(dev);
xhci_deregister(dev);
if (reset_valid(&plat->reset))
reset_free(&plat->reset);
return 0;
}
static const struct udevice_id xhci_pci_ids[] = {
{ .compatible = "xhci-pci" },
{ }
};
U_BOOT_DRIVER(xhci_pci) = {
.name = "xhci_pci",
.id = UCLASS_USB,
.probe = xhci_pci_probe,
.remove = xhci_pci_remove,
.of_match = xhci_pci_ids,
.ops = &xhci_usb_ops,
.plat_auto = sizeof(struct xhci_pci_plat),
.priv_auto = sizeof(struct xhci_ctrl),
.flags = DM_FLAG_OS_PREPARE | DM_FLAG_ALLOC_PRIV_DMA,
};
static struct pci_device_id xhci_pci_supported[] = {
{ PCI_DEVICE_CLASS(PCI_CLASS_SERIAL_USB_XHCI, ~0) },
{},
};
U_BOOT_PCI_DEVICE(xhci_pci, xhci_pci_supported);