]> git.baikalelectronics.ru Git - kernel.git/commit
PCI: aardvark: Increase polling delay to 1.5s while waiting for PIO response
authorPali Rohár <pali@kernel.org>
Thu, 22 Jul 2021 14:40:39 +0000 (16:40 +0200)
committerLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Thu, 5 Aug 2021 09:51:49 +0000 (10:51 +0100)
commitf34b2d12d3ff42229ab2f5db55984cd6cb17a5c9
tree74584f16ae0b0b8d5f10d2e879bee4140917493a
parentddcf9e4a2648c8b2f9c8b3082b256d7ca15d47cf
PCI: aardvark: Increase polling delay to 1.5s while waiting for PIO response

Measurements in different conditions showed that aardvark hardware PIO
response can take up to 1.44s. Increase wait timeout from 1ms to 1.5s to
ensure that we do not miss responses from hardware. After 1.44s hardware
returns errors (e.g. Completer abort).

The previous two patches fixed checking for PIO status, so now we can use
it to also catch errors which are reported by hardware after 1.44s.

After applying this patch, kernel can detect and print PIO errors to dmesg:

    [    6.879999] advk-pcie d0070000.pcie: Non-posted PIO Response Status: CA, 0xe00 @ 0x100004
    [    6.896436] advk-pcie d0070000.pcie: Posted PIO Response Status: COMP_ERR, 0x804 @ 0x100004
    [    6.913049] advk-pcie d0070000.pcie: Posted PIO Response Status: COMP_ERR, 0x804 @ 0x100010
    [    6.929663] advk-pcie d0070000.pcie: Non-posted PIO Response Status: CA, 0xe00 @ 0x100010
    [    6.953558] advk-pcie d0070000.pcie: Posted PIO Response Status: COMP_ERR, 0x804 @ 0x100014
    [    6.970170] advk-pcie d0070000.pcie: Non-posted PIO Response Status: CA, 0xe00 @ 0x100014
    [    6.994328] advk-pcie d0070000.pcie: Posted PIO Response Status: COMP_ERR, 0x804 @ 0x100004

Without this patch kernel prints only a generic error to dmesg:

    [    5.246847] advk-pcie d0070000.pcie: config read/write timed out

Link: https://lore.kernel.org/r/20210722144041.12661-3-pali@kernel.org
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: Marek Behún <kabel@kernel.org>
Cc: stable@vger.kernel.org # 9524bf359591 ("PCI: aardvark: Don't rely on jiffies while holding spinlock")
drivers/pci/controller/pci-aardvark.c