edac: mpc85xx mask ecc syndrome correctly
With a 64-bit wide data bus only the lowest 8-bits of the ECC syndrome are
relevant. With a 32-bit wide data bus only the lowest 16-bits are
relevant on most architectures.
Without this change, the ECC syndrome displayed can be mildly confusing,
eg:
EDAC MPC85xx MC1: syndrome: 0x25252525
When in reality the ECC syndrome is 0x25.
A variety of Freescale manuals say a variety of different things about how
to decode the CAPTURE_ECC (syndrome) register. I don't have a system with
a 32-bit bus to test on, but I believe the change is correct. It'd be
good to get an ACK from someone at Freescale about this change though.
Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
Signed-off-by: Doug Thompson <dougthompson@xmission.com>
Cc: Kumar Gala <galak@gate.crashing.org>
Cc: Dave Jiang <djiang@mvista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/edac/mpc85xx_edac.c b/drivers/edac/mpc85xx_edac.c
index ecd5928..6d0114a 100644
--- a/drivers/edac/mpc85xx_edac.c
+++ b/drivers/edac/mpc85xx_edac.c
@@ -672,6 +672,7 @@
{
struct mpc85xx_mc_pdata *pdata = mci->pvt_info;
struct csrow_info *csrow;
+ u32 bus_width;
u32 err_detect;
u32 syndrome;
u32 err_addr;
@@ -692,6 +693,15 @@
}
syndrome = in_be32(pdata->mc_vbase + MPC85XX_MC_CAPTURE_ECC);
+
+ /* Mask off appropriate bits of syndrome based on bus width */
+ bus_width = (in_be32(pdata->mc_vbase + MPC85XX_MC_DDR_SDRAM_CFG) &
+ DSC_DBW_MASK) ? 32 : 64;
+ if (bus_width == 64)
+ syndrome &= 0xff;
+ else
+ syndrome &= 0xffff;
+
err_addr = in_be32(pdata->mc_vbase + MPC85XX_MC_CAPTURE_ADDRESS);
pfn = err_addr >> PAGE_SHIFT;
@@ -707,7 +717,7 @@
mpc85xx_mc_printk(mci, KERN_ERR, "Capture Data Low: %#8.8x\n",
in_be32(pdata->mc_vbase +
MPC85XX_MC_CAPTURE_DATA_LO));
- mpc85xx_mc_printk(mci, KERN_ERR, "syndrome: %#8.8x\n", syndrome);
+ mpc85xx_mc_printk(mci, KERN_ERR, "syndrome: %#2.2x\n", syndrome);
mpc85xx_mc_printk(mci, KERN_ERR, "err addr: %#8.8x\n", err_addr);
mpc85xx_mc_printk(mci, KERN_ERR, "PFN: %#8.8x\n", pfn);