2 * This file is part of the coreboot project.
4 * Copyright (C) 2007 Advanced Micro Devices, Inc.
5 * Copyright (C) 2010 Nils Jacobs
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
21 #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 */
22 #define GX2_STACK_END GX2_STACK_BASE+(CONFIG_DCACHE_RAM_SIZE-1)
24 #define GX2_NUM_CACHELINES 0x080 /* there are 128lines per way */
25 #define GX2_CACHELINE_SIZE 0x020 /* there are 32bytes per line */
26 #define GX2_CACHEWAY_SIZE (GX2_NUM_CACHELINES * GX2_CACHELINE_SIZE)
27 #define CR0_CD 0x40000000 /* bit 30 = Cache Disable */
28 #define CR0_NW 0x20000000 /* bit 29 = Not Write Through */
29 #include <cpu/amd/gx2def.h>
30 #include <cpu/x86/post_code.h>
31 /***************************************************************************
35 /** Setup data cache for use as RAM for a stack.
37 /** Max. size data cache =0x4000 (16KB)
39 /***************************************************************************/
41 /* Save the BIST result */
45 /* set cache properties */
46 movl $CPU_RCONF_DEFAULT, %ecx
48 movl $0x010010000, %eax /*1MB system memory in write back 1|00100|00 */
51 /* in GX2 DCDIS is set after POR which disables the cache..., clear this bit */
52 movl $CPU_DM_CONFIG0, %ecx
54 andl $(~(DM_CONFIG0_LOWER_DCDIS_SET)), %eax /* TODO: make consistent with i$ init, either whole reg = 0, or just this bit... */
62 /* DCache Ways0 through Ways3 will be tagged for GX2_STACK_BASE + CONFIG_DCACHE_RAM_SIZE for holding stack */
63 /* remember, there is NO stack yet... */
65 /* Tell cache we want to fill WAY 0 starting at the top */
68 movl $CPU_DC_INDEX, %ecx
71 /* startaddress for tag of Way0: ebp will hold the incrementing address. dont destroy! */
72 movl $GX2_STACK_BASE, %ebp /* init to start address */
73 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 */
75 /* start tag Ways 0 with 128 lines with 32bytes each: edi will hold the line counter. dont destroy! */
76 movl $GX2_NUM_CACHELINES, %edi
79 /* fill with dummy data: zero it so we can tell it from PCI memory space (returns FFs). */
80 /* We will now store a line (32 bytes = 4 x 8bytes = 4 quadWords) */
84 movl $CPU_DC_DATA, %ecx
85 DCacheSetup_quadWordLoop:
88 jnz DCacheSetup_quadWordLoop
90 /* Set the tag for this line,need to do this for every new cache line to validate it! */
91 /* accessing CPU_DC_TAG_I makes the LINE field in CPU_DC_INDEX increment and thus cont. in the next cache line... */
94 movl $CPU_DC_TAG, %ecx
97 /* switch to next line */
98 /* lines are in Bits8:2 */
99 /* when index is crossing 0x7F -> 0x80 writing a RSVD bit as 0x80 is not a valid CL anymore! */
100 movl $CPU_DC_INDEX, %ecx
102 addl $0x04, %eax /* inc DC_LINE. TODO: prob. would be more elegant to calc. this from counter var edi... */
106 jnz DCacheSetupFillWay
108 /* 1 Way has been filled, forward start address for next Way, terminate if we have reached end of desired address range */
109 addl $GX2_CACHEWAY_SIZE, %ebp
110 cmpl $GX2_STACK_END, %ebp
111 jge leave_DCacheSetup
112 movl $GX2_NUM_CACHELINES, %edi
114 /* switch to next way */
115 movl $CPU_DC_INDEX, %ecx
118 andl $0xFFFFFE03, %eax /* lets be sure: reset line index Bits8:2 */
121 jmp DCacheSetupFillWay
128 /* Disable the cache, but ... DO NOT INVALIDATE the tags. */
129 /* Memory reads and writes will all hit in the cache. */
130 /* Cache updates and memory write-backs will not occur ! */
132 orl $(CR0_CD + CR0_NW), %eax /* set the CD and NW bits */
135 /* Now point sp to the cached stack. */
136 /* The stack will be fully functional at this location. No system memory is required at all ! */
137 /* set up the stack pointer */
138 movl $GX2_STACK_END, %eax
142 movl $0x0F0F05A5A, %edx
153 /* Go do early init and memory setup */
155 /* Restore the BIST result */
162 /* Call romstage.c main function */
164 done_cache_as_ram_main:
166 /* We now run over the stack-in-cache, copying it back to itself to invalidate the cache */
169 mov $(CONFIG_DCACHE_RAM_SIZE/4),%ecx
171 mov $(CONFIG_DCACHE_RAM_BASE),%edi
174 rep movsl %ds:(%esi),%es:(%edi)
178 /* Clear the cache out to ram */
180 /* re-enable the cache */
182 xorl $(CR0_CD + CR0_NW), %eax /* clear the CD and NW bits */
185 /* clear boot_complete flag */
188 post_code(POST_PREPARE_RAMSTAGE)
190 /* TODO For suspend/resume the cache will have to live between
191 * CONFIG_RAMBASE and CONFIG_RAMTOP
194 cld /* clear direction flag */
196 /* copy coreboot from it's initial load location to
197 * the location it is compiled to run at.
198 * Normally this is copying from FLASH ROM to RAM.
205 post_code(POST_DEAD_CODE)