diff options
Diffstat (limited to 'cpu/ppc4xx/start.S')
| -rw-r--r-- | cpu/ppc4xx/start.S | 33 |
1 files changed, 27 insertions, 6 deletions
diff --git a/cpu/ppc4xx/start.S b/cpu/ppc4xx/start.S index f2b8908b9..ac96fc28f 100644 --- a/cpu/ppc4xx/start.S +++ b/cpu/ppc4xx/start.S @@ -257,6 +257,14 @@ bl board_init_f #endif +#if defined(CONFIG_SYS_RAMBOOT) + /* + * 4xx RAM-booting U-Boot image is started from offset 0 + */ + .text + bl _start_440 +#endif + /* * 440 Startup -- on reset only the top 4k of the effective * address space is mapped in by an entry in the instruction @@ -444,10 +452,17 @@ skip_debug_init: addis r0,0,0x0000 li r1,0x003f /* 64 TLB entries */ mtctr r1 -rsttlb: tlbwe r0,r1,0x0000 /* Invalidate all entries (V=0)*/ - tlbwe r0,r1,0x0001 - tlbwe r0,r1,0x0002 - subi r1,r1,0x0001 + li r4,0 /* Start with TLB #0 */ +rsttlb: +#ifdef CONFIG_SYS_RAMBOOT + tlbre r3,r4,0 /* Read contents from TLB word #0 to get EPN */ + rlwinm. r3,r3,0,0xfffffc00 /* Mask EPN */ + beq tlbnxt /* Skip EPN=0 TLB, this is the SDRAM TLB */ +#endif + tlbwe r0,r4,0 /* Invalidate all entries (V=0)*/ + tlbwe r0,r4,1 + tlbwe r0,r4,2 +tlbnxt: addi r4,r4,1 /* Next TLB */ bdnz rsttlb /*----------------------------------------------------------------*/ @@ -476,7 +491,13 @@ rsttlb: tlbwe r0,r1,0x0000 /* Invalidate all entries (V=0)*/ li r4,0 /* TLB # */ addi r5,r5,-4 -1: lwzu r0,4(r5) +1: +#ifdef CONFIG_SYS_RAMBOOT + tlbre r3,r4,0 /* Read contents from TLB word #0 */ + rlwinm. r3,r3,0,0x00000200 /* Mask V (valid) bit */ + bne tlbnx2 /* Skip V=1 TLB, this is the SDRAM TLB */ +#endif + lwzu r0,4(r5) cmpwi r0,0 beq 2f /* 0 marks end */ lwzu r1,4(r5) @@ -484,7 +505,7 @@ rsttlb: tlbwe r0,r1,0x0000 /* Invalidate all entries (V=0)*/ tlbwe r0,r4,0 /* TLB Word 0 */ tlbwe r1,r4,1 /* TLB Word 1 */ tlbwe r2,r4,2 /* TLB Word 2 */ - addi r4,r4,1 /* Next TLB */ +tlbnx2: addi r4,r4,1 /* Next TLB */ bdnz 1b /*----------------------------------------------------------------*/ |