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>
git-mirror · Aug 28, 2009 · 14e0e67 · 14e0e67
1 parent 613f776
commit 14e0e67
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Showing 6 changed files with 449 additions and 19 deletions.
diff --git a/arch/arm/mach-omap2/iommu2.c b/arch/arm/mach-omap2/iommu2.c
@@ -217,10 +217,19 @@ static ssize_t omap2_dump_cr(struct iommu *obj, struct cr_regs *cr, char *buf)
 }
 
 #define pr_reg(name)							\
-	p += sprintf(p, "%20s: %08x\n",					\
-		     __stringify(name), iommu_read_reg(obj, MMU_##name));
-
-static ssize_t omap2_iommu_dump_ctx(struct iommu *obj, char *buf)
+	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, ssize_t len)
 {
 	char *p = buf;
 
@@ -242,7 +251,7 @@ static ssize_t omap2_iommu_dump_ctx(struct iommu *obj, char *buf)
 	pr_reg(READ_CAM);
 	pr_reg(READ_RAM);
 	pr_reg(EMU_FAULT_AD);
-
+out:
 	return p - buf;
 }
 

diff --git a/arch/arm/plat-omap/Kconfig b/arch/arm/plat-omap/Kconfig
@@ -120,6 +120,10 @@ config OMAP_MBOX_FWK
 config OMAP_IOMMU
 	tristate
 
+config OMAP_IOMMU_DEBUG
+	depends on OMAP_IOMMU
+	tristate
+
 choice
         prompt "System timer"
 	default OMAP_MPU_TIMER

diff --git a/arch/arm/plat-omap/Makefile b/arch/arm/plat-omap/Makefile
@@ -14,6 +14,7 @@ obj-$(CONFIG_ARCH_OMAP16XX) += ocpi.o
 
 obj-$(CONFIG_OMAP_MCBSP) += mcbsp.o
 obj-$(CONFIG_OMAP_IOMMU) += iommu.o iovmm.o
+obj-$(CONFIG_OMAP_IOMMU_DEBUG) += iommu-debug.o
 
 obj-$(CONFIG_CPU_FREQ) += cpu-omap.o
 obj-$(CONFIG_OMAP_DM_TIMER) += dmtimer.o

diff --git a/arch/arm/plat-omap/include/mach/iommu.h b/arch/arm/plat-omap/include/mach/iommu.h
@@ -95,7 +95,7 @@ struct iommu_functions {
 
 	void (*save_ctx)(struct iommu *obj);
 	void (*restore_ctx)(struct iommu *obj);
-	ssize_t (*dump_ctx)(struct iommu *obj, char *buf);
+	ssize_t (*dump_ctx)(struct iommu *obj, char *buf, ssize_t len);
 };
 
 struct iommu_platform_data {
@@ -162,7 +162,7 @@ extern void uninstall_iommu_arch(const struct iommu_functions *ops);
 extern int foreach_iommu_device(void *data,
 				int (*fn)(struct device *, void *));
 
-extern ssize_t iommu_dump_ctx(struct iommu *obj, char *buf);
-extern size_t dump_tlb_entries(struct iommu *obj, char *buf);
+extern ssize_t iommu_dump_ctx(struct iommu *obj, char *buf, ssize_t len);
+extern size_t dump_tlb_entries(struct iommu *obj, char *buf, ssize_t len);
 
 #endif /* __MACH_IOMMU_H */