[Skiboot] [PATCH v2 7/9] opal: Recover from TFMR DEC parity error.

[Mahesh J Salgaonkar]

From: Mahesh Salgaonkar <mahesh at linux.vnet.ibm.com>

Recovery process for TFMR DEC parity error:
- Set DEC Register with all ones.
- Reset TFMR DEC parity error bit.

To inject TFMR DEC parity error issue:
        $ putscom pu.ex 10013281 0006080000000000 -all

Signed-off-by: Mahesh Salgaonkar <mahesh at linux.vnet.ibm.com>
---
 hw/chiptod.c        |   11 ++++++++++-
 include/processor.h |    1 +
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/hw/chiptod.c b/hw/chiptod.c
index 6f6800f..1c77cb7 100644
--- a/hw/chiptod.c
+++ b/hw/chiptod.c
@@ -697,6 +697,14 @@ static bool tfmr_recover_non_tb_errors(uint64_t tfmr)
 		tfmr_reset_errors |= SPR_TFMR_HDEC_PARITY_ERROR;
 	}
 
+	if (tfmr & SPR_TFMR_DEC_PARITY_ERR) {
+		/* Set DEC with all ones */
+		mtspr(SPR_DEC, ~0);
+
+		/* set bit 59 to clear TFMR DEC parity error. */
+		tfmr_reset_errors |= SPR_TFMR_DEC_PARITY_ERR;
+	}
+
 	/* Write TFMR twice to clear the error */
 	mtspr(SPR_TFMR, base_tfmr | tfmr_reset_errors);
 	mtspr(SPR_TFMR, base_tfmr | tfmr_reset_errors);
@@ -848,7 +856,8 @@ int chiptod_recover_tb_errors(void)
 	/*
 	 * Now that TB is running, check for TFMR non-TB errors.
 	 */
-	if (tfmr & SPR_TFMR_HDEC_PARITY_ERROR) {
+	if ((tfmr & SPR_TFMR_HDEC_PARITY_ERROR) ||
+		(tfmr & SPR_TFMR_DEC_PARITY_ERR)) {
 		if (!tfmr_recover_non_tb_errors(tfmr)) {
 			rc = 0;
 			goto error_out;
diff --git a/include/processor.h b/include/processor.h
index 9140564..30527b1 100644
--- a/include/processor.h
+++ b/include/processor.h
@@ -47,6 +47,7 @@
 /* SPR register definitions */
 #define SPR_DSISR	0x012	/* RW: Data storage interrupt status reg */
 #define SPR_DAR		0x013	/* RW: Data address reg */
+#define SPR_DEC		0x016	/* RW: Decrement Register */
 #define SPR_SDR1	0x019
 #define SPR_SRR0	0x01a	/* RW: Exception save/restore reg 0 */
 #define SPR_SRR1	0x01b	/* RW: Exception save/restore reg 1 */