From 24f06716cd5dbfc3d737ec2a24ac58ef76f68dc7 Mon Sep 17 00:00:00 2001 From: Ariel Elior Date: Sun, 6 May 2012 07:05:57 +0000 Subject: [PATCH] bnx2x: bug fix when loading after SAN boot This is a bug fix for an "interface fails to load" issue. The issue occurs when bnx2x driver loads after UNDI driver was previously loaded over the chip. In such a scenario the UNDI driver is loaded and operates in the pre-boot kernel, within its own specific host memory address range. When the pre-boot stage is complete, the real kernel is loaded, in a new and distinct host memory address range. The transition from pre-boot stage to boot is asynchronous from UNDI point of view. A race condition occurs when UNDI driver triggers a DMAE transaction to valid host addresses in the pre-boot stage, when control is diverted to the real kernel. This results in access to illegal addresses by our HW as the addresses which were valid in the preboot stage are no longer considered valid. Specifically, the 'was_error' bit in the pci glue of our device is set. This causes all following pci transactions from chip to host to timeout (in accordance to the pci spec). Signed-off-by: Ariel Elior Signed-off-by: Eilon Greenstein Signed-off-by: David S. Miller --- .../net/ethernet/broadcom/bnx2x/bnx2x_main.c | 23 ++++++++++++++++++- 1 file changed, 22 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c index e077d2508727..6af310195bae 100644 --- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c +++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_main.c @@ -9122,13 +9122,34 @@ static int __devinit bnx2x_prev_unload_common(struct bnx2x *bp) return bnx2x_prev_mcp_done(bp); } +/* previous driver DMAE transaction may have occurred when pre-boot stage ended + * and boot began, or when kdump kernel was loaded. Either case would invalidate + * the addresses of the transaction, resulting in was-error bit set in the pci + * causing all hw-to-host pcie transactions to timeout. If this happened we want + * to clear the interrupt which detected this from the pglueb and the was done + * bit + */ +static void __devinit bnx2x_prev_interrupted_dmae(struct bnx2x *bp) +{ + u32 val = REG_RD(bp, PGLUE_B_REG_PGLUE_B_INT_STS); + if (val & PGLUE_B_PGLUE_B_INT_STS_REG_WAS_ERROR_ATTN) { + BNX2X_ERR("was error bit was found to be set in pglueb upon startup. Clearing"); + REG_WR(bp, PGLUE_B_REG_WAS_ERROR_PF_7_0_CLR, 1 << BP_FUNC(bp)); + } +} + static int __devinit bnx2x_prev_unload(struct bnx2x *bp) { int time_counter = 10; u32 rc, fw, hw_lock_reg, hw_lock_val; BNX2X_DEV_INFO("Entering Previous Unload Flow\n"); - /* Release previously held locks */ + /* clear hw from errors which may have resulted from an interrupted + * dmae transaction. + */ + bnx2x_prev_interrupted_dmae(bp); + + /* Release previously held locks */ hw_lock_reg = (BP_FUNC(bp) <= 5) ? (MISC_REG_DRIVER_CONTROL_1 + BP_FUNC(bp) * 8) : (MISC_REG_DRIVER_CONTROL_7 + (BP_FUNC(bp) - 6) * 8); -- 2.20.1