diff options
| -rw-r--r-- | src/soc/intel/common/block/cpu/car/cache_as_ram.S | 50 |
1 files changed, 44 insertions, 6 deletions
diff --git a/src/soc/intel/common/block/cpu/car/cache_as_ram.S b/src/soc/intel/common/block/cpu/car/cache_as_ram.S index 3817fa5b9933..db1345ac4271 100644 --- a/src/soc/intel/common/block/cpu/car/cache_as_ram.S +++ b/src/soc/intel/common/block/cpu/car/cache_as_ram.S @@ -12,6 +12,35 @@ .section .init, "ax", @progbits .code32 + +/* + * macro: find_free_mtrr + * Clobbers: %eax, %ebx, %ecx, %edx. + * Returns: + * %ebx contains the number of freely available MTRR's. + * It should be checked against 0. + * %ecx holds the MTRR_BASE of the free MTRR. + */ +.macro find_free_mtrr + /* Figure out how many MTRRs we have */ + mov $MTRR_CAP_MSR, %ecx + rdmsr + movzb %al, %ebx /* Number of variable MTRRs */ + + /* Find a free variable MTRR */ + movl $MTRR_PHYS_MASK(0), %ecx +1: + rdmsr + test $MTRR_PHYS_MASK_VALID, %eax + jz 2f + addl $2, %ecx + dec %ebx + jnz 1b +2: + /* %ecx needs to hold the MTRR_BASE */ + decl %ecx +.endm + .global bootblock_pre_c_entry bootblock_pre_c_entry: @@ -82,15 +111,18 @@ clear_var_mtrr: post_code(0x24) #if ((CONFIG_DCACHE_RAM_SIZE & (CONFIG_DCACHE_RAM_SIZE - 1)) == 0) + find_free_mtrr + test %ebx, %ebx + jz .halt_forever + /* Configure CAR region as write-back (WB) */ - mov $MTRR_PHYS_BASE(0), %ecx mov $CONFIG_DCACHE_RAM_BASE, %eax or $MTRR_TYPE_WRBACK, %eax xor %edx,%edx wrmsr /* Configure the MTRR mask for the size region */ - mov $MTRR_PHYS_MASK(0), %ecx + inc %ecx mov $CONFIG_DCACHE_RAM_SIZE, %eax /* size mask */ dec %eax not %eax @@ -98,14 +130,17 @@ clear_var_mtrr: movl %esi, %edx /* edx <- MTRR_PHYS_MASK_HIGH */ wrmsr #elif (CONFIG_DCACHE_RAM_SIZE == 768 * KiB) /* 768 KiB */ + find_free_mtrr + test %ebx, %ebx + jz .halt_forever + /* Configure CAR region as write-back (WB) */ - mov $MTRR_PHYS_BASE(0), %ecx mov $CONFIG_DCACHE_RAM_BASE, %eax or $MTRR_TYPE_WRBACK, %eax xor %edx,%edx wrmsr - mov $MTRR_PHYS_MASK(0), %ecx + incl %ecx mov $(512 * KiB), %eax /* size mask */ dec %eax not %eax @@ -113,13 +148,16 @@ clear_var_mtrr: movl %esi, %edx /* edx <- MTRR_PHYS_MASK_HIGH */ wrmsr - mov $MTRR_PHYS_BASE(1), %ecx + find_free_mtrr + test %ebx, %ebx + jz .halt_forever +1: mov $(CONFIG_DCACHE_RAM_BASE + 512 * KiB), %eax or $MTRR_TYPE_WRBACK, %eax xor %edx,%edx wrmsr - mov $MTRR_PHYS_MASK(1), %ecx + incl %ecx mov $(256 * KiB), %eax /* size mask */ dec %eax not %eax |