EDAC/altera: Do less intrusive error injection

Improve the Arria10 and Stratix10 error injection routine
by reading the data and changing just 1 bit before writing
back out. Previous routine would overwrite the first bytes
to 0 then change 1 bit but this method is less intrusive.

Signed-off-by: Thor Thayer <thor.thayer@linux.intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: James Morse <james.morse@arm.com>
Cc: Mauro Carvalho Chehab <mchehab@kernel.org>
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: https://lkml.kernel.org/r/1553635771-32693-1-git-send-email-thor.thayer@linux.intel.com

diff --git a/drivers/edac/altera_edac.c b/drivers/edac/altera_edac.c
index 5ff263850cc718b4722e51908f6d2b06225427b5..acb3006df6315db90450a74d1f79afc3aa6bdd60 100644 (file)
--- a/drivers/edac/altera_edac.c
+++ b/drivers/edac/altera_edac.c
@@ -1762,28 +1762,24 @@ static ssize_t altr_edac_a10_device_trig2(struct file *file,
        if (trig_type == ALTR_UE_TRIGGER_CHAR) {
                writel(priv->ue_set_mask, set_addr);
        } else {
-               /* Setup write of 0 to first 4 bytes */
-               writel(0x0, drvdata->base + ECC_BLK_WDATA0_OFST);
-               writel(0x0, drvdata->base + ECC_BLK_WDATA1_OFST);
-               writel(0x0, drvdata->base + ECC_BLK_WDATA2_OFST);
-               writel(0x0, drvdata->base + ECC_BLK_WDATA3_OFST);
-               /* Setup write of 4 bytes */
+               /* Setup read/write of 4 bytes */
                writel(ECC_WORD_WRITE, drvdata->base + ECC_BLK_DBYTECTRL_OFST);
                /* Setup Address to 0 */
-               writel(0x0, drvdata->base + ECC_BLK_ADDRESS_OFST);
-               /* Setup accctrl to write & data override */
-               writel(ECC_WRITE_DOVR, drvdata->base + ECC_BLK_ACCCTRL_OFST);
-               /* Kick it. */
-               writel(ECC_XACT_KICK, drvdata->base + ECC_BLK_STARTACC_OFST);
-               /* Setup accctrl to read & ecc override */
-               writel(ECC_READ_EOVR, drvdata->base + ECC_BLK_ACCCTRL_OFST);
+               writel(0, drvdata->base + ECC_BLK_ADDRESS_OFST);
+               /* Setup accctrl to read & ecc & data override */
+               writel(ECC_READ_EDOVR, drvdata->base + ECC_BLK_ACCCTRL_OFST);
                /* Kick it. */
                writel(ECC_XACT_KICK, drvdata->base + ECC_BLK_STARTACC_OFST);
                /* Setup write for single bit change */
-               writel(0x1, drvdata->base + ECC_BLK_WDATA0_OFST);
-               writel(0x0, drvdata->base + ECC_BLK_WDATA1_OFST);
-               writel(0x0, drvdata->base + ECC_BLK_WDATA2_OFST);
-               writel(0x0, drvdata->base + ECC_BLK_WDATA3_OFST);
+               writel(readl(drvdata->base + ECC_BLK_RDATA0_OFST) ^ 0x1,
+                      drvdata->base + ECC_BLK_WDATA0_OFST);
+               writel(readl(drvdata->base + ECC_BLK_RDATA1_OFST),
+                      drvdata->base + ECC_BLK_WDATA1_OFST);
+               writel(readl(drvdata->base + ECC_BLK_RDATA2_OFST),
+                      drvdata->base + ECC_BLK_WDATA2_OFST);
+               writel(readl(drvdata->base + ECC_BLK_RDATA3_OFST),
+                      drvdata->base + ECC_BLK_WDATA3_OFST);
+
                /* Copy Read ECC to Write ECC */
                writel(readl(drvdata->base + ECC_BLK_RECC0_OFST),
                       drvdata->base + ECC_BLK_WECC0_OFST);

diff --git a/drivers/edac/altera_edac.h b/drivers/edac/altera_edac.h
index 60513f201ffb42df0c0397524aa44283ef8b5f8c..1532ec9c3510feb924c46bb2f95e50dbc164f84c 100644 (file)
--- a/drivers/edac/altera_edac.h
+++ b/drivers/edac/altera_edac.h
@@ -321,7 +321,7 @@ struct altr_sdram_mc_data {
 #define ECC_BLK_STARTACC_OFST             0x7C
 
 #define ECC_XACT_KICK                     0x10000
-#define ECC_WORD_WRITE                    0xF
+#define ECC_WORD_WRITE                    0xFF
 #define ECC_WRITE_DOVR                    0x101
 #define ECC_WRITE_EDOVR                   0x103
 #define ECC_READ_EOVR                     0x2