| #include <variant/core.h> |
| #include <asm/regs.h> |
| #include <asm/asmmacro.h> |
| #include <asm/cacheasm.h> |
| /* |
| * RB-Data: RedBoot data/bss |
| * P: Boot-Parameters |
| * L: Kernel-Loader |
| * |
| * The Linux-Kernel image including the loader must be loaded |
| * to a position so that the kernel and the boot parameters |
| * can fit in the space before the load address. |
| * ______________________________________________________ |
| * |_RB-Data_|_P_|__________|_L_|___Linux-Kernel___|______| |
| * ^ |
| * ^ Load address |
| * ______________________________________________________ |
| * |___Linux-Kernel___|_P_|_L_|___________________________| |
| * |
| * The loader copies the parameter to the position that will |
| * be the end of the kernel and itself to the end of the |
| * parameter list. |
| */ |
| |
| /* Make sure we have enough space for the 'uncompressor' */ |
| |
| #define STACK_SIZE 32768 |
| #define HEAP_SIZE (131072*4) |
| |
| # a2: Parameter list |
| # a3: Size of parameter list |
| |
| .section .start, "ax" |
| |
| .globl __start |
| /* this must be the first byte of the loader! */ |
| __start: |
| entry sp, 32 # we do not intend to return |
| _call0 _start |
| __start_a0: |
| .align 4 |
| |
| .section .text, "ax" |
| .begin literal_prefix .text |
| |
| /* put literals in here! */ |
| |
| .globl _start |
| _start: |
| |
| /* 'reset' window registers */ |
| |
| movi a4, 1 |
| wsr a4, PS |
| rsync |
| |
| rsr a5, WINDOWBASE |
| ssl a5 |
| sll a4, a4 |
| wsr a4, WINDOWSTART |
| rsync |
| |
| movi a4, 0x00040000 |
| wsr a4, PS |
| rsync |
| |
| /* copy the loader to its address |
| * Note: The loader itself is a very small piece, so we assume we |
| * don't partially overlap. We also assume (even more important) |
| * that the kernel image is out of the way. Usually, when the |
| * load address of this image is not at an arbitrary address, |
| * but aligned to some 10K's we shouldn't overlap. |
| */ |
| |
| /* Note: The assembler cannot relax "addi a0, a0, ..." to an |
| l32r, so we load to a4 first. */ |
| |
| # addi a4, a0, __start - __start_a0 |
| # mov a0, a4 |
| |
| movi a4, __start |
| movi a5, __start_a0 |
| add a4, a0, a4 |
| sub a0, a4, a5 |
| |
| movi a4, __start |
| movi a5, __reloc_end |
| |
| # a0: address where this code has been loaded |
| # a4: compiled address of __start |
| # a5: compiled end address |
| |
| mov.n a7, a0 |
| mov.n a8, a4 |
| |
| 1: |
| l32i a10, a7, 0 |
| l32i a11, a7, 4 |
| s32i a10, a8, 0 |
| s32i a11, a8, 4 |
| l32i a10, a7, 8 |
| l32i a11, a7, 12 |
| s32i a10, a8, 8 |
| s32i a11, a8, 12 |
| addi a8, a8, 16 |
| addi a7, a7, 16 |
| blt a8, a5, 1b |
| |
| |
| /* We have to flush and invalidate the caches here before we jump. */ |
| |
| #if XCHAL_DCACHE_IS_WRITEBACK |
| |
| ___flush_dcache_all a5 a6 |
| |
| #endif |
| |
| ___invalidate_icache_all a5 a6 |
| isync |
| |
| movi a11, _reloc |
| jx a11 |
| |
| .globl _reloc |
| _reloc: |
| |
| /* RedBoot is now at the end of the memory, so we don't have |
| * to copy the parameter list. Keep the code around; in case |
| * we need it again. */ |
| #if 0 |
| # a0: load address |
| # a2: start address of parameter list |
| # a3: length of parameter list |
| # a4: __start |
| |
| /* copy the parameter list out of the way */ |
| |
| movi a6, _param_start |
| add a3, a2, a3 |
| 2: |
| l32i a8, a2, 0 |
| s32i a8, a6, 0 |
| addi a2, a2, 4 |
| addi a6, a6, 4 |
| blt a2, a3, 2b |
| #endif |
| |
| /* clear BSS section */ |
| movi a6, __bss_start |
| movi a7, __bss_end |
| movi.n a5, 0 |
| 3: |
| s32i a5, a6, 0 |
| addi a6, a6, 4 |
| blt a6, a7, 3b |
| |
| movi a5, -16 |
| movi a1, _stack + STACK_SIZE |
| and a1, a1, a5 |
| |
| /* Uncompress the kernel */ |
| |
| # a0: load address |
| # a2: boot parameter |
| # a4: __start |
| |
| movi a3, __image_load |
| sub a4, a3, a4 |
| add a8, a0, a4 |
| |
| # a1 Stack |
| # a8(a4) Load address of the image |
| |
| movi a6, _image_start |
| movi a10, _image_end |
| movi a7, 0x1000000 |
| sub a11, a10, a6 |
| movi a9, complen |
| s32i a11, a9, 0 |
| |
| movi a0, 0 |
| |
| # a6 destination |
| # a7 maximum size of destination |
| # a8 source |
| # a9 ptr to length |
| |
| .extern gunzip |
| movi a4, gunzip |
| beqz a4, 1f |
| |
| callx4 a4 |
| |
| j 2f |
| |
| |
| # a6 destination start |
| # a7 maximum size of destination |
| # a8 source start |
| # a9 ptr to length |
| # a10 destination end |
| |
| 1: |
| l32i a9, a8, 0 |
| l32i a11, a8, 4 |
| s32i a9, a6, 0 |
| s32i a11, a6, 4 |
| l32i a9, a8, 8 |
| l32i a11, a8, 12 |
| s32i a9, a6, 8 |
| s32i a11, a6, 12 |
| addi a6, a6, 16 |
| addi a8, a8, 16 |
| blt a6, a10, 1b |
| |
| |
| /* jump to the kernel */ |
| 2: |
| #if XCHAL_DCACHE_IS_WRITEBACK |
| |
| ___flush_dcache_all a5 a6 |
| |
| #endif |
| |
| ___invalidate_icache_all a5 a6 |
| |
| isync |
| |
| movi a5, __start |
| movi a3, boot_initrd_start |
| movi a4, boot_initrd_end |
| sub a3, a3, a5 |
| sub a4, a4, a5 |
| add a3, a0, a3 |
| add a4, a0, a4 |
| |
| # a2 Boot parameter list |
| # a3 initrd_start (virtual load address) |
| # a4 initrd_end (virtual load address) |
| |
| movi a0, _image_start |
| jx a0 |
| |
| .align 16 |
| .data |
| .globl avail_ram |
| avail_ram: |
| .long _heap |
| .globl end_avail |
| end_avail: |
| .long _heap + HEAP_SIZE |
| |
| .comm _stack, STACK_SIZE |
| .comm _heap, HEAP_SIZE |
| |
| .globl end_avail |
| .comm complen, 4 |
| |
| .end literal_prefix |
