mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
* [PATCH] EDAC/altera: Handle OCRAM ECC enable after warm reset
@ 2025-11-03 14:09 niravkumarlaxmidas.rabara
  2025-11-06  4:49 ` Dinh Nguyen
  2025-11-09 18:57 ` Borislav Petkov
  0 siblings, 2 replies; 4+ messages in thread
From: niravkumarlaxmidas.rabara @ 2025-11-03 14:09 UTC (permalink / raw)
  To: dinguyen, bp, tony.luck; +Cc: linux-edac, linux-kernel, Niravkumar L Rabara

From: Niravkumar L Rabara <niravkumarlaxmidas.rabara@altera.com>

The OCRAM ECC is always enabled either by the BootROM or by the Secure
Device Manager (SDM) during a power-on reset on SoCFPGA.

However, during a warm reset, the OCRAM content is retained to preserve
data, while the control and status registers are reset to their default
values. As a result, ECC must be explicitly re-enabled after a warm reset.

Signed-off-by: Niravkumar L Rabara <niravkumarlaxmidas.rabara@altera.com>
---
 drivers/edac/altera_edac.c | 18 +++++++++++++++---
 1 file changed, 15 insertions(+), 3 deletions(-)

diff --git a/drivers/edac/altera_edac.c b/drivers/edac/altera_edac.c
index 103b2c2eba2a..a776d61027f2 100644
--- a/drivers/edac/altera_edac.c
+++ b/drivers/edac/altera_edac.c
@@ -1184,10 +1184,22 @@ altr_check_ocram_deps_init(struct altr_edac_device_dev *device)
 	if (ret)
 		return ret;
 
-	/* Verify OCRAM has been initialized */
+	/*
+	 * Verify that OCRAM has been initialized.
+	 * During a warm reset, OCRAM contents are retained, but the control
+	 * and status registers are reset to their default values. Therefore,
+	 * ECC must be explicitly re-enabled in the control register.
+	 * Error condition: if INITCOMPLETEA is clear and ECC_EN is already set.
+	 */
 	if (!ecc_test_bits(ALTR_A10_ECC_INITCOMPLETEA,
-			   (base + ALTR_A10_ECC_INITSTAT_OFST)))
-		return -ENODEV;
+			   (base + ALTR_A10_ECC_INITSTAT_OFST))) {
+		if (!ecc_test_bits(ALTR_A10_ECC_EN,
+				   (base + ALTR_A10_ECC_CTRL_OFST)))
+			ecc_set_bits(ALTR_A10_ECC_EN,
+				     (base + ALTR_A10_ECC_CTRL_OFST));
+		else
+			return -ENODEV;
+	}
 
 	/* Enable IRQ on Single Bit Error */
 	writel(ALTR_A10_ECC_SERRINTEN, (base + ALTR_A10_ECC_ERRINTENS_OFST));
-- 
2.25.1


^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2025-11-11  7:13 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2025-11-03 14:09 [PATCH] EDAC/altera: Handle OCRAM ECC enable after warm reset niravkumarlaxmidas.rabara
2025-11-06  4:49 ` Dinh Nguyen
2025-11-09 18:57 ` Borislav Petkov
2025-11-11  7:13   ` Niravkumar L Rabara

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®