diff options
Diffstat (limited to 'qemu/roms/u-boot/board/jse/init.S')
| -rw-r--r-- | qemu/roms/u-boot/board/jse/init.S | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/qemu/roms/u-boot/board/jse/init.S b/qemu/roms/u-boot/board/jse/init.S new file mode 100644 index 000000000..4e449fef2 --- /dev/null +++ b/qemu/roms/u-boot/board/jse/init.S @@ -0,0 +1,75 @@ +/* + * SPDX-License-Identifier: GPL-2.0 IBM-pibs + */ +/*------------------------------------------------------------------------- */ +/* Function: ext_bus_cntlr_init */ +/* Description: Initializes the External Bus Controller for the external */ +/* peripherals. IMPORTANT: For pass1 this code must run from */ +/* cache since you can not reliably change a peripheral banks */ +/* timing register (pbxap) while running code from that bank. */ +/* For ex., since we are running from ROM on bank 0, we can NOT */ +/* execute the code that modifies bank 0 timings from ROM, so */ +/* we run it from cache. */ +/* */ +/* */ +/* The layout for the PEI JSE board: */ +/* Bank 0 - Flash and SRAM */ +/* Bank 1 - SystemACE */ +/* Bank 2 - not used */ +/* Bank 3 - not used */ +/* Bank 4 - not used */ +/* Bank 5 - not used */ +/* Bank 6 - not used */ +/* Bank 7 - not used */ +/*------------------------------------------------------------------------- */ +#include <asm/ppc4xx.h> + +#include <ppc_asm.tmpl> +#include <ppc_defs.h> + +#include <asm/cache.h> +#include <asm/mmu.h> + + .globl ext_bus_cntlr_init +ext_bus_cntlr_init: + mflr r4 /* save link register */ + bl ..getAddr +..getAddr: + mflr r3 /* get address of ..getAddr */ + mtlr r4 /* restore link register */ + addi r4,0,14 /* set ctr to 10; used to prefetch */ + mtctr r4 /* 10 cache lines to fit this function */ + /* in cache (gives us 8x10=80 instrctns) */ +..ebcloop: + icbt r0,r3 /* prefetch cache line for addr in r3 */ + addi r3,r3,32 /* move to next cache line */ + bdnz ..ebcloop /* continue for 10 cache lines */ + + /*----------------------------------------------------------------- */ + /* Delay to ensure all accesses to ROM are complete before changing */ + /* bank 0 timings. 200usec should be enough. */ + /* 200,000,000 (cycles/sec) X .000200 (sec) = 0x9C40 cycles */ + /*----------------------------------------------------------------- */ + addis r3,0,0x0 + ori r3,r3,0xA000 /* ensure 200usec have passed since reset */ + mtctr r3 +..spinlp: + bdnz ..spinlp /* spin loop */ + + /*----------------------------------------------------------------- */ + /* Memory Bank 0 (Flash) initialization */ + /*----------------------------------------------------------------- */ + + addi r4,0,PB1AP + mtdcr EBC0_CFGADDR,r4 + addis r4,0,0x9B01 + ori r4,r4,0x5480 + mtdcr EBC0_CFGDATA,r4 + + addi r4,0,PB0CR + mtdcr EBC0_CFGADDR,r4 + addis r4,0,0xFFF1 /* BAS=0xFFF,BS=0x0(1MB),BU=0x3(R/W), */ + ori r4,r4,0x8000 /* BW=0x0( 8 bits) */ + mtdcr EBC0_CFGDATA,r4 + + blr |