/* * This file is part of the coreboot project. * * Copyright (C) 2007 Advanced Micro Devices, Inc. * Copyright (C) 2010 Nils Jacobs * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #define GX2_STACK_BASE CONFIG_DCACHE_RAM_BASE /* this is where the DCache will be mapped and be used as stack, It would be cool if it was the same base as coreboot normal stack */ #define GX2_STACK_END GX2_STACK_BASE+(CONFIG_DCACHE_RAM_SIZE-1) #define GX2_NUM_CACHELINES 0x080 /* there are 128lines per way */ #define GX2_CACHELINE_SIZE 0x020 /* there are 32bytes per line */ #define GX2_CACHEWAY_SIZE (GX2_NUM_CACHELINES * GX2_CACHELINE_SIZE) #define CR0_CD 0x40000000 /* bit 30 = Cache Disable */ #define CR0_NW 0x20000000 /* bit 29 = Not Write Through */ #include /*************************************************************************** /** /** DCacheSetup /** /** Setup data cache for use as RAM for a stack. /** /** Max. size data cache =0x4000 (16KB) /** /***************************************************************************/ DCacheSetup: /* Save the BIST result */ movl %eax, %ebx invd /* set cache properties */ movl $CPU_RCONF_DEFAULT, %ecx rdmsr movl $0x010010000, %eax /*1MB system memory in write back 1|00100|00 */ wrmsr /* in GX2 DCDIS is set after POR which disables the cache..., clear this bit */ movl $CPU_DM_CONFIG0, %ecx rdmsr andl $(~(DM_CONFIG0_LOWER_DCDIS_SET)), %eax /* TODO: make consistent with i$ init, either whole reg = 0, or just this bit... */ wrmsr /* Get cleaned up. */ xorl %edi, %edi xorl %esi, %esi xorl %ebp, %ebp /* DCache Ways0 through Ways3 will be tagged for GX2_STACK_BASE + CONFIG_DCACHE_RAM_SIZE for holding stack */ /* remember, there is NO stack yet... */ /* Tell cache we want to fill WAY 0 starting at the top */ xorl %edx, %edx xorl %eax, %eax movl $CPU_DC_INDEX, %ecx wrmsr /* startaddress for tag of Way0: ebp will hold the incrementing address. dont destroy! */ movl $GX2_STACK_BASE, %ebp /* init to start address */ orl $1, %ebp /* set valid bit and tag for this Way (B[31:12] : Cache tag value for line/way curr. selected by CPU_DC_INDEX */ /* start tag Ways 0 with 128 lines with 32bytes each: edi will hold the line counter. dont destroy! */ movl $GX2_NUM_CACHELINES, %edi DCacheSetupFillWay: /* fill with dummy data: zero it so we can tell it from PCI memory space (returns FFs). */ /* We will now store a line (32 bytes = 4 x 8bytes = 4 quadWords) */ movw $0x04, %si xorl %edx, %edx xorl %eax, %eax movl $CPU_DC_DATA, %ecx DCacheSetup_quadWordLoop: wrmsr decw %si jnz DCacheSetup_quadWordLoop /* Set the tag for this line,need to do this for every new cache line to validate it! */ /* accessing CPU_DC_TAG_I makes the LINE field in CPU_DC_INDEX increment and thus cont. in the next cache line... */ xorl %edx, %edx movl %ebp, %eax movl $CPU_DC_TAG, %ecx wrmsr /* switch to next line */ /* lines are in Bits8:2 */ /* when index is crossing 0x7F -> 0x80 writing a RSVD bit as 0x80 is not a valid CL anymore! */ movl $CPU_DC_INDEX, %ecx rdmsr addl $0x04, %eax /* inc DC_LINE. TODO: prob. would be more elegant to calc. this from counter var edi... */ wrmsr decl %edi jnz DCacheSetupFillWay /* 1 Way has been filled, forward start address for next Way, terminate if we have reached end of desired address range */ addl $GX2_CACHEWAY_SIZE, %ebp cmpl $GX2_STACK_END, %ebp jge leave_DCacheSetup movl $GX2_NUM_CACHELINES, %edi /* switch to next way */ movl $CPU_DC_INDEX, %ecx rdmsr addl $0x01, %eax andl $0xFFFFFE03, %eax /* lets be sure: reset line index Bits8:2 */ wrmsr jmp DCacheSetupFillWay leave_DCacheSetup: xorl %edi, %edi xorl %esi, %esi xorl %ebp, %ebp /* Disable the cache, but ... DO NOT INVALIDATE the tags. */ /* Memory reads and writes will all hit in the cache. */ /* Cache updates and memory write-backs will not occur ! */ movl %cr0, %eax orl $(CR0_CD + CR0_NW), %eax /* set the CD and NW bits */ movl %eax, %cr0 /* Now point sp to the cached stack. */ /* The stack will be fully functional at this location. No system memory is required at all ! */ /* set up the stack pointer */ movl $GX2_STACK_END, %eax movl %eax, %esp /* test the stack*/ movl $0x0F0F05A5A, %edx pushl %edx popl %ecx cmpl %ecx, %edx je DCacheSetupGood post_code(0xc5) DCacheSetupBad: hlt /* issues */ jmp DCacheSetupBad DCacheSetupGood: /* Go do early init and memory setup */ /* Restore the BIST result */ movl %ebx, %eax movl %esp, %ebp pushl %eax post_code(0x23) /* Call romstage.c main function */ call main done_cache_as_ram_main: /* We now run over the stack-in-cache, copying it back to itself to invalidate the cache */ push %edi mov $(CONFIG_DCACHE_RAM_SIZE/4),%ecx push %esi mov $(CONFIG_DCACHE_RAM_BASE),%edi mov %edi,%esi cld rep movsl %ds:(%esi),%es:(%edi) pop %esi pop %edi /* Clear the cache out to ram */ wbinvd /* re-enable the cache */ movl %cr0, %eax xorl $(CR0_CD + CR0_NW), %eax /* clear the CD and NW bits */ movl %eax, %cr0 /* clear boot_complete flag */ xorl %ebp, %ebp __main: post_code(0x11) /* TODO For suspend/resume the cache will have to live between * CONFIG_RAMBASE and CONFIG_RAMTOP */ cld /* clear direction flag */ /* copy coreboot from it's initial load location to * the location it is compiled to run at. * Normally this is copying from FLASH ROM to RAM. */ movl %ebp, %esi pushl %esi call copy_and_run .Lhlt: post_code(0xee) hlt jmp .Lhlt