| /* |
| * 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 |