bnxt_en: Re-write the BARs following any type of PCIe errors

Currently the driver zeroes the BARs only when fatal PCIe errors
are reported so that pci_restore_state() restores it.  However
firmware handles both fatal and non-fatal errors the same way when
it sees the slot reset resulting from the PCI_ERS_RESULT_NEED_RESET
return code from the driver.  This means that we must re-write the
BARs post recovery even during non-fatal errors.  Otherwise we will
see that every MMIO access returns all-ones and the firmware appears
dead.

Zero-out the BARs during PCIe error recovery regardless of type of
PCIe error, and make the wait after the hot reset unconditional.

Disable memory decode and bus mastering before rewriting the BARs so
the device doesn't decode a half-updated address, bailing out if
config space is still inaccessible.  Defer pci_enable_device() until
after the BAR rewrite and restore, so the device isn't re-enabled
while its BARs are still being rewritten, then re-enable the device
and re-assert bus mastering.  Guard the same Command register cleanup
on the re-enable failure path against an inaccessible device.

Skip re-enabling the device in bnxt_io_slot_reset() if it is already
enabled, so enable_cnt does not go unbalanced.  A concurrent
bnxt_fw_reset_task() can also be re-enabling the same device in its
ENABLE_DEV state, so guard that call the same way.

Fixes: f75d9a0aa967 ("bnxt_en: Re-write PCI BARs after PCI fatal error.")
Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Reviewed-by: Scott Branden <scott.branden@broadcom.com>
Signed-off-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://patch.msgid.link/20261005204246.3822563-4-michael.chan@broadcom.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

0 files changed, 0 insertions, 0 deletions