iommu: msm: allow partial register dumps to be printed

If we get back a partial register dump from TZ we should go ahead and
print as much as we can, rather than bailing out and not printing
anything.

Change-Id: Idcc8b14a76bf1f23bdf00b52879b3ce0ca9afdcc
Signed-off-by: Mitchel Humpherys <mitchelh@codeaurora.org>

2 files changed, 10 insertions, 4 deletions

diff --git a/drivers/iommu/msm_iommu-v1.c b/drivers/iommu/msm_iommu-v1.c
index 367285c1d00b..ee7a1f251dc3 100644
--- a/drivers/iommu/msm_iommu-v1.c
+++ b/drivers/iommu/msm_iommu-v1.c
@@ -1143,6 +1143,7 @@ void print_ctx_regs(struct msm_iommu_context_reg regs[])
 {
 	uint32_t fsr = regs[DUMP_REG_FSR].val;
 	u64 ttbr;
+	enum dump_reg iter;
 
 	pr_err("FAR    = %016llx\n",
 		COMBINE_DUMP_REG(
@@ -1186,6 +1187,11 @@ void print_ctx_regs(struct msm_iommu_context_reg regs[])
 	pr_err("CBAR  = %08x    CBFRSYNRA  = %08x\n",
 		regs[DUMP_REG_CBAR_N].val, regs[DUMP_REG_CBFRSYNRA_N].val);
 	print_ctx_mem_attr_regs(regs);
+
+	for (iter = DUMP_REG_FIRST; iter < MAX_DUMP_REGS; ++iter)
+		if (!regs[iter].valid)
+			pr_err("NOTE: Value actually unknown for %s\n",
+				dump_regs_tbl[iter].name);
 }
 
 static void __print_ctx_regs(void __iomem *base, int ctx, unsigned int fsr)
diff --git a/drivers/iommu/msm_iommu_sec.c b/drivers/iommu/msm_iommu_sec.c
index d1b891c21d7e..b0c43bf6fe06 100644
--- a/drivers/iommu/msm_iommu_sec.c
+++ b/drivers/iommu/msm_iommu_sec.c
@@ -217,7 +217,6 @@ static int msm_iommu_reg_dump_to_regs(
 	if (i != nvals) {
 		pr_err("Invalid dump! %d != %d\n", i, nvals);
 		ret = 1;
-		goto out;
 	}
 
 	for (i = 0; i < MAX_DUMP_REGS; ++i) {
@@ -231,11 +230,10 @@ static int msm_iommu_reg_dump_to_regs(
 						dump_regs_tbl[i].reg_offset));
 				ret = 1;
 			}
-			ctx_regs[i].val = 0;
+			ctx_regs[i].val = 0xd00dfeed;
 		}
 	}
 
-out:
 	return ret;
 }
 
@@ -289,7 +287,9 @@ irqreturn_t msm_iommu_secure_fault_handler_v2(int irq, void *dev_id)
 		memset(ctx_regs, 0, sizeof(ctx_regs));
 		tmp = msm_iommu_reg_dump_to_regs(
 			ctx_regs, regs, drvdata, ctx_drvdata);
-		if (!tmp && ctx_regs[DUMP_REG_FSR].val) {
+		if (ctx_regs[DUMP_REG_FSR].val) {
+			if (tmp)
+				pr_err("Incomplete fault register dump. Printout will be incomplete.\n");
 			if (!ctx_drvdata->attached_domain) {
 				pr_err("Bad domain in interrupt handler\n");
 				tmp = -ENOSYS;