[PATCH] pci: fix incorrect value returned from pcie_get_speed_cap

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



The macros PCI_EXP_LNKCAP_SLS_*GB are values, not bit masks. We must mask
the register and compare it against them.

This patch fixes errors "amdgpu: [powerplay] failed to send message 261
ret is 0" errors when PCIe-v3 card is plugged into PCIe-v1 slot, because
the slot is being incorrectly reported as PCIe-v3 capable.

Signed-off-by: Mikulas Patocka <mpatocka@xxxxxxxxxx>
Fixes: 6cf57be0f78e ("PCI: Add pcie_get_speed_cap() to find max supported link speed")
Cc: stable@xxxxxxxxxxxxxxx	# v4.17+

---
 drivers/pci/pci.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

Index: linux-4.19/drivers/pci/pci.c
===================================================================
--- linux-4.19.orig/drivers/pci/pci.c	2018-10-30 16:58:58.000000000 +0100
+++ linux-4.19/drivers/pci/pci.c	2018-10-30 16:58:58.000000000 +0100
@@ -5492,13 +5492,13 @@ enum pci_bus_speed pcie_get_speed_cap(st
 
 	pcie_capability_read_dword(dev, PCI_EXP_LNKCAP, &lnkcap);
 	if (lnkcap) {
-		if (lnkcap & PCI_EXP_LNKCAP_SLS_16_0GB)
+		if ((lnkcap & PCI_EXP_LNKCAP_SLS) == PCI_EXP_LNKCAP_SLS_16_0GB)
 			return PCIE_SPEED_16_0GT;
-		else if (lnkcap & PCI_EXP_LNKCAP_SLS_8_0GB)
+		else if ((lnkcap & PCI_EXP_LNKCAP_SLS) == PCI_EXP_LNKCAP_SLS_8_0GB)
 			return PCIE_SPEED_8_0GT;
-		else if (lnkcap & PCI_EXP_LNKCAP_SLS_5_0GB)
+		else if ((lnkcap & PCI_EXP_LNKCAP_SLS) ==PCI_EXP_LNKCAP_SLS_5_0GB)
 			return PCIE_SPEED_5_0GT;
-		else if (lnkcap & PCI_EXP_LNKCAP_SLS_2_5GB)
+		else if ((lnkcap & PCI_EXP_LNKCAP_SLS) == PCI_EXP_LNKCAP_SLS_2_5GB)
 			return PCIE_SPEED_2_5GT;
 	}
 



[Index of Archives]     [DMA Engine]     [Linux Coverity]     [Linux USB]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [Greybus]

  Powered by Linux