leandrof/u-boot
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

drivers: pci: imx: fix imx_pcie_remove function

Browse Source 
We have at least a minor count of boards, that failed to re-initialize
PCI express in the Linux kernel. Typical failure rate is 20% on affected
boards. This is mitigated by commit 6ecbe13756 ("drivers: pci: imx:
add imx_pcie_remove function").

However, at least on some i.MX6 custom boards, when calling
assert_core_reset() as part of the first-time PCIe init, read access
to PCIE_PL_PFLR simply hangs. Surround this readl() with
imx_pcie_fix_dabt_handler() does not help. For this reason, the forced
LTSSM detection is only used on the second assert_core_reset() that is
called shorly before starting the Linux kernel.

Signed-off-by: Sven-Ola Tuecke <sven-ola.tuecke@numberfour.eu>
Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Tested-by: David Müller <d.mueller@elsoft.ch>
This commit is contained in:
Sven-Ola Tuecke 2017-10-05 08:46:42 -03:00 committed by Stefano Babic
parent 066d97c733
commit b2915ba25e
1 changed files with 4 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
drivers/pci/pcie_imx.c
View File

@ -431,7 +431,7 @@ static int imx_pcie_write_config(struct pci_controller *hose, pci_dev_t d,
/* /*
* Initial bus setup * Initial bus setup
*/ */
static int imx6_pcie_assert_core_reset(void) static int imx6_pcie_assert_core_reset(bool prepare_for_boot)
{ {
struct iomuxc *iomuxc_regs = (struct iomuxc *)IOMUXC_BASE_ADDR; struct iomuxc *iomuxc_regs = (struct iomuxc *)IOMUXC_BASE_ADDR;
@ -459,7 +459,7 @@ static int imx6_pcie_assert_core_reset(void)
* If both LTSSM_ENABLE and REF_SSP_ENABLE are active we have a strong * If both LTSSM_ENABLE and REF_SSP_ENABLE are active we have a strong
* indication that the bootloader activated the link. * indication that the bootloader activated the link.
*/ */
if (is_mx6dq()) { if (is_mx6dq() && prepare_for_boot) {
u32 val, gpr1, gpr12; u32 val, gpr1, gpr12;
gpr1 = readl(&iomuxc_regs->gpr[1]); gpr1 = readl(&iomuxc_regs->gpr[1]);
@ -605,7 +605,7 @@ static int imx_pcie_link_up(void)
uint32_t tmp; uint32_t tmp;
int count = 0; int count = 0;
imx6_pcie_assert_core_reset(); imx6_pcie_assert_core_reset(false);
imx6_pcie_init_phy(); imx6_pcie_init_phy();
imx6_pcie_deassert_core_reset(); imx6_pcie_deassert_core_reset();
@ -687,7 +687,7 @@ void imx_pcie_init(void)
void imx_pcie_remove(void) void imx_pcie_remove(void)
{ {
imx6_pcie_assert_core_reset(); imx6_pcie_assert_core_reset(true);
} }
/* Probe function. */ /* Probe function. */