powerpc/8xx: add CONFIG_PIN_TLB_IMMR
CONFIG_PIN_TLB maps IMMR area and the first 24 Mbytes of memory.
In some circunstances it might be more interesting to not map
IMMR but map 32 Mbytes of memory instead.
Therefore we add config option CONFIG_PIN_TLB_IMMR to select if
IMMR shall be pinned or not, hence whether we pin 24 or 32 Mbytes of RAM
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Scott Wood <oss@buserror.net>
diff --git a/arch/powerpc/mm/8xx_mmu.c b/arch/powerpc/mm/8xx_mmu.c
index 0f0a83e..6c5025e 100644
--- a/arch/powerpc/mm/8xx_mmu.c
+++ b/arch/powerpc/mm/8xx_mmu.c
@@ -61,11 +61,15 @@
#ifdef CONFIG_PIN_TLB
unsigned long ctr = mfspr(SPRN_MD_CTR) & 0xfe000000;
unsigned long flags = 0xf0 | MD_SPS16K | _PAGE_SHARED | _PAGE_DIRTY;
- int i;
+#ifdef CONFIG_PIN_TLB_IMMR
+ int i = 29;
+#else
+ int i = 28;
+#endif
unsigned long addr = 0;
unsigned long mem = total_lowmem;
- for (i = 29; i < 32 && mem >= LARGE_PAGE_SIZE_8M; i++) {
+ for (; i < 32 && mem >= LARGE_PAGE_SIZE_8M; i++) {
mtspr(SPRN_MD_CTR, ctr | (i << 8));
mtspr(SPRN_MD_EPN, (unsigned long)__va(addr) | MD_EVALID);
mtspr(SPRN_MD_TWC, MD_PS8MEG | MD_SVALID);
@@ -88,7 +92,7 @@
}
/* Address of instructions to patch */
-#ifndef CONFIG_PIN_TLB
+#ifndef CONFIG_PIN_TLB_IMMR
extern unsigned int DTLBMiss_jmp;
#endif
extern unsigned int DTLBMiss_cmp, FixupDAR_cmp;
@@ -109,7 +113,7 @@
if (__map_without_ltlbs) {
mapped = 0;
mmu_mapin_immr();
-#ifndef CONFIG_PIN_TLB
+#ifndef CONFIG_PIN_TLB_IMMR
patch_instruction(&DTLBMiss_jmp, PPC_INST_NOP);
#endif
} else {