EDAC, altera: Add panic flag check to A10 IRQ

In preparation for additional memory module ECCs, the IRQ function will
check a panic flag before doing a kernel panic on double bit errors.

OCRAM uncorrectable errors cause a panic because sleep/resume functions
and FPGA contents during sleep are stored in OCRAM.

ECCs on peripheral FIFO buffers will not cause a kernel panic on DBERRs
because the packet can be retried and therefore recovered.

Signed-off-by: Thor Thayer <tthayer@opensource.altera.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/1466603939-7526-3-git-send-email-tthayer@opensource.altera.com
Signed-off-by: Borislav Petkov <bp@suse.de>

2 files changed, 9 insertions, 1 deletions

diff --git a/drivers/edac/altera_edac.c b/drivers/edac/altera_edac.c
index 453e92c786c8..dcedc4a8cd12 100644
--- a/drivers/edac/altera_edac.c
+++ b/drivers/edac/altera_edac.c
@@ -897,7 +897,8 @@ static irqreturn_t altr_edac_a10_ecc_irq(int irq, void *dev_id)
                 writel(ALTR_A10_ECC_DERRPENA,
                        base + ALTR_A10_ECC_INTSTAT_OFST);
                 edac_device_handle_ue(dci->edac_dev, 0, 0, dci->edac_dev_name);
-                panic("\nEDAC:ECC_DEVICE[Uncorrectable errors]\n");
+                if (dci->data->panic)
+                        panic("\nEDAC:ECC_DEVICE[Uncorrectable errors]\n");
 
                 return IRQ_HANDLED;
         }
@@ -936,6 +937,12 @@ static const struct edac_device_prv_data a10_ocramecc_data = {
         .set_err_ofst = ALTR_A10_ECC_INTTEST_OFST,
         .ecc_irq_handler = altr_edac_a10_ecc_irq,
         .inject_fops = &altr_edac_a10_device_inject_fops,
+        /*
+         * OCRAM panic on uncorrectable error because sleep/resume
+         * functions and FPGA contents are stored in OCRAM. Prefer
+         * a kernel panic over executing/loading corrupted data.
+         */
+        .panic = true,
 };
 
 #endif  /* CONFIG_EDAC_ALTERA_OCRAM */
diff --git a/drivers/edac/altera_edac.h b/drivers/edac/altera_edac.h
index 62b0fa010f95..cf4e8cb1d120 100644
--- a/drivers/edac/altera_edac.h
+++ b/drivers/edac/altera_edac.h
@@ -298,6 +298,7 @@ struct edac_device_prv_data {
         irqreturn_t (*ecc_irq_handler)(int irq, void *dev_id);
         int trig_alloc_sz;
         const struct file_operations *inject_fops;
+        bool panic;
 };
 
 struct altr_edac_device_dev {