[PATCH] MIPS: R3000: Fix debug output for Virtual page number

[PATCH] MIPS: R3000: Fix debug output for Virtual page number

[Isamu Mogi]

Virtual page number of R3000 in entryhi is 20 bit from MSB. But in
dump_tlb(), the bit mask to read it from entryhi is 19 bit (0xffffe000).
The patch fixes that to 0xfffff000.

Signed-off-by: Isamu Mogi <isamu@leafytree.jp>
---
 arch/mips/lib/r3k_dump_tlb.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/mips/lib/r3k_dump_tlb.c b/arch/mips/lib/r3k_dump_tlb.c
index 91615c2..1ef365a 100644
--- a/arch/mips/lib/r3k_dump_tlb.c
+++ b/arch/mips/lib/r3k_dump_tlb.c
@@ -34,7 +34,7 @@ static void dump_tlb(int first, int last)
 		entrylo0 = read_c0_entrylo0();
 
 		/* Unused entries have a virtual address of KSEG0.  */
-		if ((entryhi & 0xffffe000) != 0x80000000
+		if ((entryhi & 0xfffff000) != 0x80000000
 		    && (entryhi & 0xfc0) == asid) {
 			/*
 			 * Only print entries in use
@@ -43,7 +43,7 @@ static void dump_tlb(int first, int last)
 
 			printk("va=%08lx asid=%08lx"
 			       "  [pa=%06lx n=%d d=%d v=%d g=%d]",
-			       (entryhi & 0xffffe000),
+			       (entryhi & 0xfffff000),
 			       entryhi & 0xfc0,
 			       entrylo0 & PAGE_MASK,
 			       (entrylo0 & (1 << 11)) ? 1 : 0,
-- 
1.8.4.5

Re: [PATCH] MIPS: R3000: Fix debug output for Virtual page number

[Maciej W. Rozycki]

On Wed, 10 Sep 2014, Isamu Mogi wrote:

> Virtual page number of R3000 in entryhi is 20 bit from MSB. But in
> dump_tlb(), the bit mask to read it from entryhi is 19 bit (0xffffe000).
> The patch fixes that to 0xfffff000.
> 
> Signed-off-by: Isamu Mogi <isamu@leafytree.jp>

Acked-by: Maciej W. Rozycki <macro@linux-mips.org>

 It would be good to add appropriate macros to <asm/mipsregs.h> too, to 
avoid magic numbers and decrease the likelihood of issues like this.  As a 
separate change, that is, of course, and not a prerequisite.

  Maciej

[PATCH v2 0/3] MIPS: R3000: Fix debug output for Virtual page number

[Isamu Mogi]

This patch set fixes the bit mask for MIPS R3000's virtual page number in
debug output. Also replace magic numbers with macros to decrease the
likelihood of issues like this.

Changes in v2:
- Replace magic numbers with macros
- Remove redundant parentheses

Isamu Mogi (3):
  MIPS: R3000: Fix debug output for Virtual page number
  MIPS: R3000: Replace magic numbers with macros
  MIPS: R3000: Remove redundant parentheses

 arch/mips/lib/r3k_dump_tlb.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

-- 
1.9.1

[PATCH v2 1/3] MIPS: R3000: Fix debug output for Virtual page number

[Isamu Mogi]

Virtual page number of R3000 in entryhi is 20 bit from MSB. But in
dump_tlb(), the bit mask to read it from entryhi is 19 bit (0xffffe000).
The patch fixes that to 0xfffff000.

Signed-off-by: Isamu Mogi <isamu@leafytree.jp>
---
 arch/mips/lib/r3k_dump_tlb.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/mips/lib/r3k_dump_tlb.c b/arch/mips/lib/r3k_dump_tlb.c
index 91615c2..1ef365a 100644
--- a/arch/mips/lib/r3k_dump_tlb.c
+++ b/arch/mips/lib/r3k_dump_tlb.c
@@ -34,7 +34,7 @@ static void dump_tlb(int first, int last)
 		entrylo0 = read_c0_entrylo0();
 
 		/* Unused entries have a virtual address of KSEG0.  */
-		if ((entryhi & 0xffffe000) != 0x80000000
+		if ((entryhi & 0xfffff000) != 0x80000000
 		    && (entryhi & 0xfc0) == asid) {
 			/*
 			 * Only print entries in use
@@ -43,7 +43,7 @@ static void dump_tlb(int first, int last)
 
 			printk("va=%08lx asid=%08lx"
 			       "  [pa=%06lx n=%d d=%d v=%d g=%d]",
-			       (entryhi & 0xffffe000),
+			       (entryhi & 0xfffff000),
 			       entryhi & 0xfc0,
 			       entrylo0 & PAGE_MASK,
 			       (entrylo0 & (1 << 11)) ? 1 : 0,
-- 
1.9.1

[PATCH v2 2/3] MIPS: R3000: Replace magic numbers with macros

[Isamu Mogi]

Also include asm/mmu_context.h for ASID_MASK.

Signed-off-by: Isamu Mogi <isamu@leafytree.jp>
---
 arch/mips/lib/r3k_dump_tlb.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/arch/mips/lib/r3k_dump_tlb.c b/arch/mips/lib/r3k_dump_tlb.c
index 1ef365a..c97bb70 100644
--- a/arch/mips/lib/r3k_dump_tlb.c
+++ b/arch/mips/lib/r3k_dump_tlb.c
@@ -9,6 +9,7 @@
 #include <linux/mm.h>
 
 #include <asm/mipsregs.h>
+#include <asm/mmu_context.h>
 #include <asm/page.h>
 #include <asm/pgtable.h>
 #include <asm/tlbdebug.h>
@@ -21,7 +22,7 @@ static void dump_tlb(int first, int last)
 	unsigned int asid;
 	unsigned long entryhi, entrylo0;
 
-	asid = read_c0_entryhi() & 0xfc0;
+	asid = read_c0_entryhi() & ASID_MASK;
 
 	for (i = first; i <= last; i++) {
 		write_c0_index(i<<8);
@@ -34,8 +35,8 @@ static void dump_tlb(int first, int last)
 		entrylo0 = read_c0_entrylo0();
 
 		/* Unused entries have a virtual address of KSEG0.  */
-		if ((entryhi & 0xfffff000) != 0x80000000
-		    && (entryhi & 0xfc0) == asid) {
+		if ((entryhi & PAGE_MASK) != KSEG0
+		    && (entryhi & ASID_MASK) == asid) {
 			/*
 			 * Only print entries in use
 			 */
@@ -43,8 +44,8 @@ static void dump_tlb(int first, int last)
 
 			printk("va=%08lx asid=%08lx"
 			       "  [pa=%06lx n=%d d=%d v=%d g=%d]",
-			       (entryhi & 0xfffff000),
-			       entryhi & 0xfc0,
+			       (entryhi & PAGE_MASK),
+			       entryhi & ASID_MASK,
 			       entrylo0 & PAGE_MASK,
 			       (entrylo0 & (1 << 11)) ? 1 : 0,
 			       (entrylo0 & (1 << 10)) ? 1 : 0,
-- 
1.9.1

[PATCH v2 3/3] MIPS: R3000: Remove redundant parentheses

[Isamu Mogi]

Signed-off-by: Isamu Mogi <isamu@leafytree.jp>
---
 arch/mips/lib/r3k_dump_tlb.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/mips/lib/r3k_dump_tlb.c b/arch/mips/lib/r3k_dump_tlb.c
index c97bb70..975a138 100644
--- a/arch/mips/lib/r3k_dump_tlb.c
+++ b/arch/mips/lib/r3k_dump_tlb.c
@@ -44,7 +44,7 @@ static void dump_tlb(int first, int last)
 
 			printk("va=%08lx asid=%08lx"
 			       "  [pa=%06lx n=%d d=%d v=%d g=%d]",
-			       (entryhi & PAGE_MASK),
+			       entryhi & PAGE_MASK,
 			       entryhi & ASID_MASK,
 			       entrylo0 & PAGE_MASK,
 			       (entrylo0 & (1 << 11)) ? 1 : 0,
-- 
1.9.1

Re: [PATCH v2 1/3] MIPS: R3000: Fix debug output for Virtual page number

[Ralf Baechle]

On Thu, Oct 30, 2014 at 10:07:36PM +0900, Isamu Mogi wrote:

> Virtual page number of R3000 in entryhi is 20 bit from MSB. But in
> dump_tlb(), the bit mask to read it from entryhi is 19 bit (0xffffe000).
> The patch fixes that to 0xfffff000.

Looks like a cut and paste issue from the R4000 code.

Will apply,

  Ralf