Patchwork powerpc/pci: fix PCI-e check link issue

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Submitter Yuanquan Chen
Date May 17, 2013, 7:35 a.m.
Message ID <1368776129-21249-1-git-send-email-Yuanquan.Chen@freescale.com>
Download mbox | patch
Permalink /patch/244515/
State Accepted, archived
Commit 36f684940017b7a5d9039861189203d64d2f8861
Delegated to: Scott Wood
Headers show

Comments

Yuanquan Chen - May 17, 2013, 7:35 a.m.
For Freescale powerpc platform, the PCI-e bus number uses the reassign mode
by default. It means the second PCI-e controller's hose->first_busno is the
first controller's last bus number adding 1. For some hotpluged device(or
controlled by FPGA), the device is linked to PCI-e slot at linux runtime.
It needs rescan for the system to add it and driver it to work. It successes
to rescan the device linked to the first PCI-e controller's slot, but fails to
rescan the device linked to the second PCI-e controller's slot. The cause is
that the bus->number is reset to 0, which isn't equal to the hose->first_busno
for the second controller checking PCI-e link. So it doesn't really check the
PCI-e link status, the link status is always no_link. The device won't be
really rescaned. Reset the bus->number to hose->first_busno in the function
fsl_pcie_check_link(), it will do the real checking PCI-e link status for the
second controller, the device will be rescaned.

Signed-off-by: Yuanquan Chen <Yuanquan.Chen@freescale.com>
---
 arch/powerpc/sysdev/fsl_pci.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
Rojhalat Ibrahim - May 21, 2013, 12:07 p.m.
On Friday 17 May 2013 15:35:29 Yuanquan Chen wrote:
> For Freescale powerpc platform, the PCI-e bus number uses the reassign mode
> by default. It means the second PCI-e controller's hose->first_busno is the
> first controller's last bus number adding 1. For some hotpluged device(or
> controlled by FPGA), the device is linked to PCI-e slot at linux runtime.
> It needs rescan for the system to add it and driver it to work. It successes
> to rescan the device linked to the first PCI-e controller's slot, but fails
> to rescan the device linked to the second PCI-e controller's slot. The
> cause is that the bus->number is reset to 0, which isn't equal to the
> hose->first_busno for the second controller checking PCI-e link. So it
> doesn't really check the PCI-e link status, the link status is always
> no_link. The device won't be really rescaned. Reset the bus->number to
> hose->first_busno in the function fsl_pcie_check_link(), it will do the
> real checking PCI-e link status for the second controller, the device will
> be rescaned.
> 
> Signed-off-by: Yuanquan Chen <Yuanquan.Chen@freescale.com>

Tested-by: Rojhalat Ibrahim <imr@rtschenk.de>


> ---
>  arch/powerpc/sysdev/fsl_pci.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/powerpc/sysdev/fsl_pci.c b/arch/powerpc/sysdev/fsl_pci.c
> index 028ac1f..534597a 100644
> --- a/arch/powerpc/sysdev/fsl_pci.c
> +++ b/arch/powerpc/sysdev/fsl_pci.c
> @@ -64,7 +64,7 @@ static int fsl_pcie_check_link(struct pci_controller
> *hose) if (hose->indirect_type & PPC_INDIRECT_TYPE_FSL_CFG_REG_LINK) {
>  		if (hose->ops->read == fsl_indirect_read_config) {
>  			struct pci_bus bus;
> -			bus.number = 0;
> +			bus.number = hose->first_busno;
>  			bus.sysdata = hose;
>  			bus.ops = hose->ops;
>  			indirect_read_config(&bus, 0, PCIE_LTSSM, 4, &val);

Patch

diff --git a/arch/powerpc/sysdev/fsl_pci.c b/arch/powerpc/sysdev/fsl_pci.c
index 028ac1f..534597a 100644
--- a/arch/powerpc/sysdev/fsl_pci.c
+++ b/arch/powerpc/sysdev/fsl_pci.c
@@ -64,7 +64,7 @@  static int fsl_pcie_check_link(struct pci_controller *hose)
 	if (hose->indirect_type & PPC_INDIRECT_TYPE_FSL_CFG_REG_LINK) {
 		if (hose->ops->read == fsl_indirect_read_config) {
 			struct pci_bus bus;
-			bus.number = 0;
+			bus.number = hose->first_busno;
 			bus.sysdata = hose;
 			bus.ops = hose->ops;
 			indirect_read_config(&bus, 0, PCIE_LTSSM, 4, &val);