OMAP: iommu: add initial debugfs support
This enables to peek the following data.
$ /debug/iommu/isp# ls
mem nr_tlb_entries regs
mmap pagetable tlb
$ /debug/iommu/isp# head pagetable
L: da: pa:
-----------------------------------------
2: 00001000 8ae4a002
2: 00002000 8e7bb002
2: 00003000 8ae49002
2: 00004000 8ae65002
.....
Signed-off-by: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
diff --git a/arch/arm/mach-omap2/iommu2.c b/arch/arm/mach-omap2/iommu2.c
index 015f22a..2d9b5cc 100644
--- a/arch/arm/mach-omap2/iommu2.c
+++ b/arch/arm/mach-omap2/iommu2.c
@@ -217,10 +217,19 @@
}
#define pr_reg(name) \
- p += sprintf(p, "%20s: %08x\n", \
- __stringify(name), iommu_read_reg(obj, MMU_##name));
+ do { \
+ ssize_t bytes; \
+ const char *str = "%20s: %08x\n"; \
+ const int maxcol = 32; \
+ bytes = snprintf(p, maxcol, str, __stringify(name), \
+ iommu_read_reg(obj, MMU_##name)); \
+ p += bytes; \
+ len -= bytes; \
+ if (len < maxcol) \
+ goto out; \
+ } while (0)
-static ssize_t omap2_iommu_dump_ctx(struct iommu *obj, char *buf)
+static ssize_t omap2_iommu_dump_ctx(struct iommu *obj, char *buf, ssize_t len)
{
char *p = buf;
@@ -242,7 +251,7 @@
pr_reg(READ_CAM);
pr_reg(READ_RAM);
pr_reg(EMU_FAULT_AD);
-
+out:
return p - buf;
}