From: Maciej W. Rozycki <macro@orcam.me.uk>
Date: Sun, 29 Mar 2026 18:07:41 +0000 (+0100)
Subject: declance: Include the offending address with DMA errors
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=aae5efaeb8aa4ada710d5b0cdbab77b9539c69eb;p=thirdparty%2Flinux.git

declance: Include the offending address with DMA errors

The address latched in the I/O ASIC LANCE DMA Pointer Register uses the
TURBOchannel bus address encoding and therefore bits 33:29 of location
referred occupy bits 4:0, bits 28:2 are left-shifted by 3, and bits 1:0
are hardwired to zero.  In reality no TURBOchannel system exceeds 1GiB
of RAM though, so the address reported will always fit in 8 hex digits.

Signed-off-by: Maciej W. Rozycki <macro@orcam.me.uk>
Link: https://patch.msgid.link/alpine.DEB.2.21.2603291839220.60268@angie.orcam.me.uk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---

diff --git a/drivers/net/ethernet/amd/declance.c b/drivers/net/ethernet/amd/declance.c
index 24aa4803b4ae..c7d47ca603a8 100644
--- a/drivers/net/ethernet/amd/declance.c
+++ b/drivers/net/ethernet/amd/declance.c
@@ -726,8 +726,10 @@ out:
 static irqreturn_t lance_dma_merr_int(int irq, void *dev_id)
 {
 	struct net_device *dev = dev_id;
+	u64 ldp = ioasic_read(IO_REG_LANCE_DMA_P);
 
-	pr_err_ratelimited("%s: DMA error\n", dev->name);
+	pr_err_ratelimited("%s: DMA error at %#010llx\n", dev->name,
+			   (ldp & 0x1f) << 29 | (ldp & 0xffffffe0) >> 3);
 	return IRQ_HANDLED;
 }