[ARM] Convert set_pte_ext implementions to macros

There are actually only four separate implementations of set_pte_ext.
Use assembler macros to insert code for these into the proc-*.S files.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 144 insertions, 0 deletions

diff --git a/arch/arm/mm/proc-macros.S b/arch/arm/mm/proc-macros.S
index b13150052a76..d1be25313d7b 100644
--- a/arch/arm/mm/proc-macros.S
+++ b/arch/arm/mm/proc-macros.S
@@ -71,3 +71,147 @@
         mov     \reg, #16                       @ size offset
         mov     \reg, \reg, lsl \tmp            @ actual cache line size
         .endm
+
+
+/*
+ * Sanity check the PTE configuration for the code below - which makes
+ * certain assumptions about how these bits are layed out.
+ */
+#if L_PTE_SHARED != PTE_EXT_SHARED
+#error PTE shared bit mismatch
+#endif
+#if L_PTE_BUFFERABLE != PTE_BUFFERABLE
+#error PTE bufferable bit mismatch
+#endif
+#if L_PTE_CACHEABLE != PTE_CACHEABLE
+#error PTE cacheable bit mismatch
+#endif
+#if (L_PTE_EXEC+L_PTE_USER+L_PTE_WRITE+L_PTE_DIRTY+L_PTE_YOUNG+\
+     L_PTE_FILE+L_PTE_PRESENT) > L_PTE_SHARED
+#error Invalid Linux PTE bit settings
+#endif
+
+/*
+ * The ARMv6 and ARMv7 set_pte_ext translation function.
+ *
+ * Permission translation:
+ *  YUWD  APX AP1 AP0   SVC     User
+ *  0xxx   0   0   0    no acc  no acc
+ *  100x   1   0   1    r/o     no acc
+ *  10x0   1   0   1    r/o     no acc
+ *  1011   0   0   1    r/w     no acc
+ *  110x   0   1   0    r/w     r/o
+ *  11x0   0   1   0    r/w     r/o
+ *  1111   0   1   1    r/w     r/w
+ */
+        .macro  armv6_set_pte_ext
+        str     r1, [r0], #-2048                @ linux version
+
+        bic     r3, r1, #0x000003f0
+        bic     r3, r3, #PTE_TYPE_MASK
+        orr     r3, r3, r2
+        orr     r3, r3, #PTE_EXT_AP0 | 2
+
+        tst     r1, #L_PTE_WRITE
+        tstne   r1, #L_PTE_DIRTY
+        orreq   r3, r3, #PTE_EXT_APX
+
+        tst     r1, #L_PTE_USER
+        orrne   r3, r3, #PTE_EXT_AP1
+        tstne   r3, #PTE_EXT_APX
+        bicne   r3, r3, #PTE_EXT_APX | PTE_EXT_AP0
+
+        tst     r1, #L_PTE_EXEC
+        orreq   r3, r3, #PTE_EXT_XN
+
+        tst     r1, #L_PTE_YOUNG
+        tstne   r1, #L_PTE_PRESENT
+        moveq   r3, #0
+
+        str     r3, [r0]
+        mcr     p15, 0, r0, c7, c10, 1          @ flush_pte
+        .endm
+
+
+/*
+ * The ARMv3, ARMv4 and ARMv5 set_pte_ext translation function,
+ * covering most CPUs except Xscale and Xscale 3.
+ *
+ * Permission translation:
+ *  YUWD   AP   SVC     User
+ *  0xxx  0x00  no acc  no acc
+ *  100x  0x00  r/o     no acc
+ *  10x0  0x00  r/o     no acc
+ *  1011  0x55  r/w     no acc
+ *  110x  0xaa  r/w     r/o
+ *  11x0  0xaa  r/w     r/o
+ *  1111  0xff  r/w     r/w
+ */
+        .macro  armv3_set_pte_ext wc_disable=1
+        str     r1, [r0], #-2048                @ linux version
+
+        eor     r3, r1, #L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_WRITE | L_PTE_DIRTY
+
+        bic     r2, r1, #PTE_SMALL_AP_MASK      @ keep C, B bits
+        bic     r2, r2, #PTE_TYPE_MASK
+        orr     r2, r2, #PTE_TYPE_SMALL
+
+        tst     r3, #L_PTE_USER                 @ user?
+        orrne   r2, r2, #PTE_SMALL_AP_URO_SRW
+
+        tst     r3, #L_PTE_WRITE | L_PTE_DIRTY  @ write and dirty?
+        orreq   r2, r2, #PTE_SMALL_AP_UNO_SRW
+
+        tst     r3, #L_PTE_PRESENT | L_PTE_YOUNG        @ present and young?
+        movne   r2, #0
+
+        .if     \wc_disable
+#ifdef CONFIG_CPU_DCACHE_WRITETHROUGH
+        tst     r2, #PTE_CACHEABLE
+        bicne   r2, r2, #PTE_BUFFERABLE
+#endif
+        .endif
+        str     r2, [r0]                        @ hardware version
+        .endm
+
+
+/*
+ * Xscale set_pte_ext translation, split into two halves to cope
+ * with work-arounds.  r3 must be preserved by code between these
+ * two macros.
+ *
+ * Permission translation:
+ *  YUWD  AP    SVC     User
+ *  0xxx  00    no acc  no acc
+ *  100x  00    r/o     no acc
+ *  10x0  00    r/o     no acc
+ *  1011  01    r/w     no acc
+ *  110x  10    r/w     r/o
+ *  11x0  10    r/w     r/o
+ *  1111  11    r/w     r/w
+ */
+        .macro  xscale_set_pte_ext_prologue
+        str     r1, [r0], #-2048                @ linux version
+
+        eor     r3, r1, #L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_WRITE | L_PTE_DIRTY
+
+        bic     r2, r1, #PTE_SMALL_AP_MASK      @ keep C, B bits
+        orr     r2, r2, #PTE_TYPE_EXT           @ extended page
+
+        tst     r3, #L_PTE_USER                 @ user?
+        orrne   r2, r2, #PTE_EXT_AP_URO_SRW     @ yes -> user r/o, system r/w
+
+        tst     r3, #L_PTE_WRITE | L_PTE_DIRTY  @ write and dirty?
+        orreq   r2, r2, #PTE_EXT_AP_UNO_SRW     @ yes -> user n/a, system r/w
+                                                @ combined with user -> user r/w
+        .endm
+
+        .macro  xscale_set_pte_ext_epilogue
+        tst     r3, #L_PTE_PRESENT | L_PTE_YOUNG        @ present and young?
+        movne   r2, #0                          @ no -> fault
+
+        str     r2, [r0]                        @ hardware version
+        mov     ip, #0
+        mcr     p15, 0, r0, c7, c10, 1          @ clean L1 D line
+        mcr     p15, 0, ip, c7, c10, 4          @ data write barrier
+        .endm