[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-Id: <20260205.170959.89574674688839340.rene@exactco.de>
Date: Thu, 05 Feb 2026 17:09:59 +0100 (CET)
From: René Rebe <rene@...ctco.de>
To: Sean Anderson <seanga2@...il.com>
Cc: Andrew Lunn <andrew+netdev@...n.ch>, "David S. Miller"
<davem@...emloft.net>, <netdev@...r.kernel.org>
Subject: [PATCH] net: sunhme: Fix sbus regression
Commit cc216e4b44ce ("net: sunhme: Switch SBUS to devres") changed
explicit sized of_ioremap with BMAC_REG_SIZEs to
devm_platform_ioremap_resource mapping all the resource. However,
this does not work on my Sun Ultra 2 with SBUS HMEs:
hme f0072f38: error -EBUSY: can't request region for resource [mem 0x1ffe8c07000-0x1ffe8c0701f]
hme f0072f38: Cannot map TCVR registers.
hme f0072f38: probe with driver hme failed with error -16
hme f007ab44: error -EBUSY: can't request region for resource [mem 0x1ff28c07000-0x1ff28c0701f]
hme f007ab44: Cannot map TCVR registers.
hme f007ab44: probe with driver hme failed with error -16
Turns out the open-firmware resources overlap, at least on this
machines and PROM version:
hexdump /proc/device-tree/sbus@1f,0/SUNW,hme@2,8c00000/reg:
00 00 00 02 08 c0 00 00 00 00 01 08
00 00 00 02 08 c0 20 00 00 00 20 00
00 00 00 02 08 c0 40 00 00 00 20 00
00 00 00 02 08 c0 60 00 00 00 20 00
00 00 00 02 08 c0 70 00 00 00 00 20
And the driver previously explicitly mapped way smaller mmio regions:
/proc/iomem:
1ff28c00000-1ff28c00107 : HME Global Regs
1ff28c02000-1ff28c02033 : HME TX Regs
1ff28c04000-1ff28c0401f : HME RX Regs
1ff28c06000-1ff28c0635f : HME BIGMAC Regs
1ff28c07000-1ff28c0701f : HME Tranceiver Regs
Quirk this specific issue by truncating the previous resource to not
overlap into the TCVR registers.
Fixes: cc216e4b44ce ("net: sunhme: Switch SBUS to devres")
Signed-off-by: René Rebe <rene@...ctco.de>
---
Tested on Sun Ultra 2 running T2/Linux.
Alternatively we could explicitly size all regions, or check overlap
in startup code (I also already have a patch for that, too).
---
--- linux-6.18/drivers/net/ethernet/sun/sunhme.c.vanilla 2026-02-05 11:50:33.288906134 +0100
+++ linux-6.18/drivers/net/ethernet/sun/sunhme.c 2026-02-05 11:55:22.541384377 +0100
@@ -2551,6 +2551,9 @@
goto err_out_clear_quattro;
}
+ /* BIGMAC may have bogus sizes */
+ if ((op->resource[3].end - op->resource[3].start) >= BMAC_REG_SIZE)
+ op->resource[3].end = op->resource[3].start + BMAC_REG_SIZE - 1;
hp->bigmacregs = devm_platform_ioremap_resource(op, 3);
if (IS_ERR(hp->bigmacregs)) {
dev_err(&op->dev, "Cannot map BIGMAC registers.\n");
--
René Rebe, ExactCODE GmbH, Berlin, Germany
https://exactco.de • https://t2linux.com • https://patreon.com/renerebe
Powered by blists - more mailing lists