diff options
Diffstat (limited to 'cpu/ppc4xx/tlb.c')
| -rw-r--r-- | cpu/ppc4xx/tlb.c | 88 |
1 files changed, 87 insertions, 1 deletions
diff --git a/cpu/ppc4xx/tlb.c b/cpu/ppc4xx/tlb.c index 098694c..ed493f1 100644 --- a/cpu/ppc4xx/tlb.c +++ b/cpu/ppc4xx/tlb.c @@ -26,6 +26,7 @@ #if defined(CONFIG_440) #include <ppc440.h> +#include <asm/cache.h> #include <asm/io.h> #include <asm/mmu.h> @@ -42,7 +43,6 @@ void remove_tlb(u32 vaddr, u32 size) u32 tlb_vaddr; u32 tlb_size = 0; - /* First, find the index of a TLB entry not being used */ for (i=0; i<PPC4XX_TLB_SIZE; i++) { tlb_word0_value = mftlb1(i); tlb_vaddr = TLB_WORD0_EPN_DECODE(tlb_word0_value); @@ -96,6 +96,92 @@ void remove_tlb(u32 vaddr, u32 size) asm("isync"); } +/* + * Change the I attribute (cache inhibited) of a TLB or multiple TLB's. + * This function is used to either turn cache on or off in a specific + * memory area. + */ +void change_tlb(u32 vaddr, u32 size, u32 tlb_word2_i_value) +{ + int i; + u32 tlb_word0_value; + u32 tlb_word2_value; + u32 tlb_vaddr; + u32 tlb_size = 0; + + for (i=0; i<PPC4XX_TLB_SIZE; i++) { + tlb_word0_value = mftlb1(i); + tlb_vaddr = TLB_WORD0_EPN_DECODE(tlb_word0_value); + if (((tlb_word0_value & TLB_WORD0_V_MASK) == TLB_WORD0_V_ENABLE) && + (tlb_vaddr >= vaddr)) { + /* + * TLB is enabled and start address is lower or equal + * than the area we are looking for. Now we only have + * to check the size/end address for a match. + */ + switch (tlb_word0_value & TLB_WORD0_SIZE_MASK) { + case TLB_WORD0_SIZE_1KB: + tlb_size = 1 << 10; + break; + case TLB_WORD0_SIZE_4KB: + tlb_size = 4 << 10; + break; + case TLB_WORD0_SIZE_16KB: + tlb_size = 16 << 10; + break; + case TLB_WORD0_SIZE_64KB: + tlb_size = 64 << 10; + break; + case TLB_WORD0_SIZE_256KB: + tlb_size = 256 << 10; + break; + case TLB_WORD0_SIZE_1MB: + tlb_size = 1 << 20; + break; + case TLB_WORD0_SIZE_16MB: + tlb_size = 16 << 20; + break; + case TLB_WORD0_SIZE_256MB: + tlb_size = 256 << 20; + break; + } + + /* + * Now check the end-address if it's in the range + */ + if ((tlb_vaddr + tlb_size - 1) <= (vaddr + size - 1)) { + /* + * Found a TLB in the range. + * Change cache attribute in tlb2 word. + */ + tlb_word2_value = + TLB_WORD2_U0_DISABLE | TLB_WORD2_U1_DISABLE | + TLB_WORD2_U2_DISABLE | TLB_WORD2_U3_DISABLE | + TLB_WORD2_W_DISABLE | tlb_word2_i_value | + TLB_WORD2_M_DISABLE | TLB_WORD2_G_DISABLE | + TLB_WORD2_E_DISABLE | TLB_WORD2_UX_ENABLE | + TLB_WORD2_UW_ENABLE | TLB_WORD2_UR_ENABLE | + TLB_WORD2_SX_ENABLE | TLB_WORD2_SW_ENABLE | + TLB_WORD2_SR_ENABLE; + + /* + * Now either flush or invalidate the dcache + */ + if (tlb_word2_i_value) + flush_dcache(); + else + invalidate_dcache(); + + mttlb3(i, tlb_word2_value); + asm("iccci 0,0"); + } + } + } + + /* Execute an ISYNC instruction so that the new TLB entry takes effect */ + asm("isync"); +} + static int add_tlb_entry(unsigned long phys_addr, unsigned long virt_addr, unsigned long tlb_word0_size_value, |