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 # 7fbcb5da ("PCI: aardvark: Don't rely on jiffies while holding spinlock")
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