Ronald G. Minnich (rminnich@gmail.com) just uploaded a new patch set to gerrit, which you can find at http://review.coreboot.org/5354
-gerrit
commit 95f8389e8a9c9e5d352e89e3ca7bd7f3c161e8b8 Author: Ronald G. Minnich rminnich@gmail.com Date: Sat Mar 8 17:33:12 2014 +0100
Enable pages. Testing for now. Do not commit
Enable paging in coreboot. We're going to have to do this at some point, when we hit x86_64; the ARM ports do paging in both 32- and 64-bit modes; MTRR is a PITA; and it's easy.
This trial example just sets up a 4G identity map using 4M pages. Not tested, just wanted to save it somewhere. The code is known to work as I've used it other places.
If this works I'll add the code later to manipulate page tables. IMHO we use this for machines where coreboot can live in the low 4G. For other cases, it's time to start thinking about 64-bit mode. The ARM V8 port is carving the way so this is as good a time as any.
This code is enabled by CONFIG_PGE, which defaults to n. To turn it on navigate to architecture options in menuconfig.
A remaining question is whether to turn off paging when we start the payload. I tend to vote 'not', since, again, ARM shows we don't have too. But we'll burn that bikeshed when we come to it. Many kernels do, however, know how to manage starting up from a bootstrap with paging enabled.
Change-Id: Iea0192e5187c47e63d25f88eaa3e88cb6c58feb1 Signed-off-by: Ronald G. Minnich rminnich@gmail.com --- src/arch/x86/Kconfig | 11 ++++ src/arch/x86/lib/c_start.S | 20 +++++++ src/arch/x86/lib/makepg.c | 11 ++++ src/arch/x86/lib/pagetables.S | 130 ++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 172 insertions(+)
diff --git a/src/arch/x86/Kconfig b/src/arch/x86/Kconfig index 8854e6b..0c0f91c 100644 --- a/src/arch/x86/Kconfig +++ b/src/arch/x86/Kconfig @@ -78,6 +78,17 @@ config UPDATE_IMAGE is a suitable file for further processing. The bootblock will not be modified.
+config PGE + bool "Enable x86 page tables." + default n + help + In original coreboot we did not use page tables. The + MTRR code just keeps getting messier and if we turn + on paging it gets very easy. We can enable disable + caching on anything down to a 4k boundary. We can + control cache disable and write-back/writethrough + on each page. For now, this code creates an identity + map for 4G using 4M pages. config ROMCC bool default n diff --git a/src/arch/x86/lib/c_start.S b/src/arch/x86/lib/c_start.S index 01ffa7c..831ebb1 100644 --- a/src/arch/x86/lib/c_start.S +++ b/src/arch/x86/lib/c_start.S @@ -31,6 +31,26 @@ _start: movl %eax, %gs
post_code(POST_ENTRY_C_START) /* post 13 */ +#ifdef CONFIG_PGE + jmp code + +#include "pagetables.S" + +code: + movl $pagetables, %ecx /* load address of page directory */ + movl %ecx, %cr3 + jmp 1f +1: + + movl %cr0, %edx + orl $0x80010000, %edx /* PG|WP */ + andl $~0x6000000A, %edx /* ~(CD|NW|TS|MP) */ + + movl $paging, %eax + movl %edx, %cr0 + jmp *%eax +paging: +#endif
cld
diff --git a/src/arch/x86/lib/makepg.c b/src/arch/x86/lib/makepg.c new file mode 100644 index 0000000..9ffa7fd --- /dev/null +++ b/src/arch/x86/lib/makepg.c @@ -0,0 +1,11 @@ +#include <stdio.h> +main(int argc, char *argv[]) +{ + int i, j; + for(i = 0; i < 1024; i += 8){ + printf("\t.long "); + for(j = 0; j < 8; j++) + printf("0x%08x,", ((i+j)<<22) + 0x105); + printf("\n"); + } +} diff --git a/src/arch/x86/lib/pagetables.S b/src/arch/x86/lib/pagetables.S new file mode 100644 index 0000000..beff3ef --- /dev/null +++ b/src/arch/x86/lib/pagetables.S @@ -0,0 +1,130 @@ +pagetables: + .align 4096 + .long 0x00000105,0x00400105,0x00800105,0x00c00105,0x01000105,0x01400105,0x01800105,0x01c00105 + .long 0x02000105,0x02400105,0x02800105,0x02c00105,0x03000105,0x03400105,0x03800105,0x03c00105 + .long 0x04000105,0x04400105,0x04800105,0x04c00105,0x05000105,0x05400105,0x05800105,0x05c00105 + .long 0x06000105,0x06400105,0x06800105,0x06c00105,0x07000105,0x07400105,0x07800105,0x07c00105 + .long 0x08000105,0x08400105,0x08800105,0x08c00105,0x09000105,0x09400105,0x09800105,0x09c00105 + .long 0x0a000105,0x0a400105,0x0a800105,0x0ac00105,0x0b000105,0x0b400105,0x0b800105,0x0bc00105 + .long 0x0c000105,0x0c400105,0x0c800105,0x0cc00105,0x0d000105,0x0d400105,0x0d800105,0x0dc00105 + .long 0x0e000105,0x0e400105,0x0e800105,0x0ec00105,0x0f000105,0x0f400105,0x0f800105,0x0fc00105 + .long 0x10000105,0x10400105,0x10800105,0x10c00105,0x11000105,0x11400105,0x11800105,0x11c00105 + .long 0x12000105,0x12400105,0x12800105,0x12c00105,0x13000105,0x13400105,0x13800105,0x13c00105 + .long 0x14000105,0x14400105,0x14800105,0x14c00105,0x15000105,0x15400105,0x15800105,0x15c00105 + .long 0x16000105,0x16400105,0x16800105,0x16c00105,0x17000105,0x17400105,0x17800105,0x17c00105 + .long 0x18000105,0x18400105,0x18800105,0x18c00105,0x19000105,0x19400105,0x19800105,0x19c00105 + .long 0x1a000105,0x1a400105,0x1a800105,0x1ac00105,0x1b000105,0x1b400105,0x1b800105,0x1bc00105 + .long 0x1c000105,0x1c400105,0x1c800105,0x1cc00105,0x1d000105,0x1d400105,0x1d800105,0x1dc00105 + .long 0x1e000105,0x1e400105,0x1e800105,0x1ec00105,0x1f000105,0x1f400105,0x1f800105,0x1fc00105 + .long 0x20000105,0x20400105,0x20800105,0x20c00105,0x21000105,0x21400105,0x21800105,0x21c00105 + .long 0x22000105,0x22400105,0x22800105,0x22c00105,0x23000105,0x23400105,0x23800105,0x23c00105 + .long 0x24000105,0x24400105,0x24800105,0x24c00105,0x25000105,0x25400105,0x25800105,0x25c00105 + .long 0x26000105,0x26400105,0x26800105,0x26c00105,0x27000105,0x27400105,0x27800105,0x27c00105 + .long 0x28000105,0x28400105,0x28800105,0x28c00105,0x29000105,0x29400105,0x29800105,0x29c00105 + .long 0x2a000105,0x2a400105,0x2a800105,0x2ac00105,0x2b000105,0x2b400105,0x2b800105,0x2bc00105 + .long 0x2c000105,0x2c400105,0x2c800105,0x2cc00105,0x2d000105,0x2d400105,0x2d800105,0x2dc00105 + .long 0x2e000105,0x2e400105,0x2e800105,0x2ec00105,0x2f000105,0x2f400105,0x2f800105,0x2fc00105 + .long 0x30000105,0x30400105,0x30800105,0x30c00105,0x31000105,0x31400105,0x31800105,0x31c00105 + .long 0x32000105,0x32400105,0x32800105,0x32c00105,0x33000105,0x33400105,0x33800105,0x33c00105 + .long 0x34000105,0x34400105,0x34800105,0x34c00105,0x35000105,0x35400105,0x35800105,0x35c00105 + .long 0x36000105,0x36400105,0x36800105,0x36c00105,0x37000105,0x37400105,0x37800105,0x37c00105 + .long 0x38000105,0x38400105,0x38800105,0x38c00105,0x39000105,0x39400105,0x39800105,0x39c00105 + .long 0x3a000105,0x3a400105,0x3a800105,0x3ac00105,0x3b000105,0x3b400105,0x3b800105,0x3bc00105 + .long 0x3c000105,0x3c400105,0x3c800105,0x3cc00105,0x3d000105,0x3d400105,0x3d800105,0x3dc00105 + .long 0x3e000105,0x3e400105,0x3e800105,0x3ec00105,0x3f000105,0x3f400105,0x3f800105,0x3fc00105 + .long 0x40000105,0x40400105,0x40800105,0x40c00105,0x41000105,0x41400105,0x41800105,0x41c00105 + .long 0x42000105,0x42400105,0x42800105,0x42c00105,0x43000105,0x43400105,0x43800105,0x43c00105 + .long 0x44000105,0x44400105,0x44800105,0x44c00105,0x45000105,0x45400105,0x45800105,0x45c00105 + .long 0x46000105,0x46400105,0x46800105,0x46c00105,0x47000105,0x47400105,0x47800105,0x47c00105 + .long 0x48000105,0x48400105,0x48800105,0x48c00105,0x49000105,0x49400105,0x49800105,0x49c00105 + .long 0x4a000105,0x4a400105,0x4a800105,0x4ac00105,0x4b000105,0x4b400105,0x4b800105,0x4bc00105 + .long 0x4c000105,0x4c400105,0x4c800105,0x4cc00105,0x4d000105,0x4d400105,0x4d800105,0x4dc00105 + .long 0x4e000105,0x4e400105,0x4e800105,0x4ec00105,0x4f000105,0x4f400105,0x4f800105,0x4fc00105 + .long 0x50000105,0x50400105,0x50800105,0x50c00105,0x51000105,0x51400105,0x51800105,0x51c00105 + .long 0x52000105,0x52400105,0x52800105,0x52c00105,0x53000105,0x53400105,0x53800105,0x53c00105 + .long 0x54000105,0x54400105,0x54800105,0x54c00105,0x55000105,0x55400105,0x55800105,0x55c00105 + .long 0x56000105,0x56400105,0x56800105,0x56c00105,0x57000105,0x57400105,0x57800105,0x57c00105 + .long 0x58000105,0x58400105,0x58800105,0x58c00105,0x59000105,0x59400105,0x59800105,0x59c00105 + .long 0x5a000105,0x5a400105,0x5a800105,0x5ac00105,0x5b000105,0x5b400105,0x5b800105,0x5bc00105 + .long 0x5c000105,0x5c400105,0x5c800105,0x5cc00105,0x5d000105,0x5d400105,0x5d800105,0x5dc00105 + .long 0x5e000105,0x5e400105,0x5e800105,0x5ec00105,0x5f000105,0x5f400105,0x5f800105,0x5fc00105 + .long 0x60000105,0x60400105,0x60800105,0x60c00105,0x61000105,0x61400105,0x61800105,0x61c00105 + .long 0x62000105,0x62400105,0x62800105,0x62c00105,0x63000105,0x63400105,0x63800105,0x63c00105 + .long 0x64000105,0x64400105,0x64800105,0x64c00105,0x65000105,0x65400105,0x65800105,0x65c00105 + .long 0x66000105,0x66400105,0x66800105,0x66c00105,0x67000105,0x67400105,0x67800105,0x67c00105 + .long 0x68000105,0x68400105,0x68800105,0x68c00105,0x69000105,0x69400105,0x69800105,0x69c00105 + .long 0x6a000105,0x6a400105,0x6a800105,0x6ac00105,0x6b000105,0x6b400105,0x6b800105,0x6bc00105 + .long 0x6c000105,0x6c400105,0x6c800105,0x6cc00105,0x6d000105,0x6d400105,0x6d800105,0x6dc00105 + .long 0x6e000105,0x6e400105,0x6e800105,0x6ec00105,0x6f000105,0x6f400105,0x6f800105,0x6fc00105 + .long 0x70000105,0x70400105,0x70800105,0x70c00105,0x71000105,0x71400105,0x71800105,0x71c00105 + .long 0x72000105,0x72400105,0x72800105,0x72c00105,0x73000105,0x73400105,0x73800105,0x73c00105 + .long 0x74000105,0x74400105,0x74800105,0x74c00105,0x75000105,0x75400105,0x75800105,0x75c00105 + .long 0x76000105,0x76400105,0x76800105,0x76c00105,0x77000105,0x77400105,0x77800105,0x77c00105 + .long 0x78000105,0x78400105,0x78800105,0x78c00105,0x79000105,0x79400105,0x79800105,0x79c00105 + .long 0x7a000105,0x7a400105,0x7a800105,0x7ac00105,0x7b000105,0x7b400105,0x7b800105,0x7bc00105 + .long 0x7c000105,0x7c400105,0x7c800105,0x7cc00105,0x7d000105,0x7d400105,0x7d800105,0x7dc00105 + .long 0x7e000105,0x7e400105,0x7e800105,0x7ec00105,0x7f000105,0x7f400105,0x7f800105,0x7fc00105 + .long 0x80000105,0x80400105,0x80800105,0x80c00105,0x81000105,0x81400105,0x81800105,0x81c00105 + .long 0x82000105,0x82400105,0x82800105,0x82c00105,0x83000105,0x83400105,0x83800105,0x83c00105 + .long 0x84000105,0x84400105,0x84800105,0x84c00105,0x85000105,0x85400105,0x85800105,0x85c00105 + .long 0x86000105,0x86400105,0x86800105,0x86c00105,0x87000105,0x87400105,0x87800105,0x87c00105 + .long 0x88000105,0x88400105,0x88800105,0x88c00105,0x89000105,0x89400105,0x89800105,0x89c00105 + .long 0x8a000105,0x8a400105,0x8a800105,0x8ac00105,0x8b000105,0x8b400105,0x8b800105,0x8bc00105 + .long 0x8c000105,0x8c400105,0x8c800105,0x8cc00105,0x8d000105,0x8d400105,0x8d800105,0x8dc00105 + .long 0x8e000105,0x8e400105,0x8e800105,0x8ec00105,0x8f000105,0x8f400105,0x8f800105,0x8fc00105 + .long 0x90000105,0x90400105,0x90800105,0x90c00105,0x91000105,0x91400105,0x91800105,0x91c00105 + .long 0x92000105,0x92400105,0x92800105,0x92c00105,0x93000105,0x93400105,0x93800105,0x93c00105 + .long 0x94000105,0x94400105,0x94800105,0x94c00105,0x95000105,0x95400105,0x95800105,0x95c00105 + .long 0x96000105,0x96400105,0x96800105,0x96c00105,0x97000105,0x97400105,0x97800105,0x97c00105 + .long 0x98000105,0x98400105,0x98800105,0x98c00105,0x99000105,0x99400105,0x99800105,0x99c00105 + .long 0x9a000105,0x9a400105,0x9a800105,0x9ac00105,0x9b000105,0x9b400105,0x9b800105,0x9bc00105 + .long 0x9c000105,0x9c400105,0x9c800105,0x9cc00105,0x9d000105,0x9d400105,0x9d800105,0x9dc00105 + .long 0x9e000105,0x9e400105,0x9e800105,0x9ec00105,0x9f000105,0x9f400105,0x9f800105,0x9fc00105 + .long 0xa0000105,0xa0400105,0xa0800105,0xa0c00105,0xa1000105,0xa1400105,0xa1800105,0xa1c00105 + .long 0xa2000105,0xa2400105,0xa2800105,0xa2c00105,0xa3000105,0xa3400105,0xa3800105,0xa3c00105 + .long 0xa4000105,0xa4400105,0xa4800105,0xa4c00105,0xa5000105,0xa5400105,0xa5800105,0xa5c00105 + .long 0xa6000105,0xa6400105,0xa6800105,0xa6c00105,0xa7000105,0xa7400105,0xa7800105,0xa7c00105 + .long 0xa8000105,0xa8400105,0xa8800105,0xa8c00105,0xa9000105,0xa9400105,0xa9800105,0xa9c00105 + .long 0xaa000105,0xaa400105,0xaa800105,0xaac00105,0xab000105,0xab400105,0xab800105,0xabc00105 + .long 0xac000105,0xac400105,0xac800105,0xacc00105,0xad000105,0xad400105,0xad800105,0xadc00105 + .long 0xae000105,0xae400105,0xae800105,0xaec00105,0xaf000105,0xaf400105,0xaf800105,0xafc00105 + .long 0xb0000105,0xb0400105,0xb0800105,0xb0c00105,0xb1000105,0xb1400105,0xb1800105,0xb1c00105 + .long 0xb2000105,0xb2400105,0xb2800105,0xb2c00105,0xb3000105,0xb3400105,0xb3800105,0xb3c00105 + .long 0xb4000105,0xb4400105,0xb4800105,0xb4c00105,0xb5000105,0xb5400105,0xb5800105,0xb5c00105 + .long 0xb6000105,0xb6400105,0xb6800105,0xb6c00105,0xb7000105,0xb7400105,0xb7800105,0xb7c00105 + .long 0xb8000105,0xb8400105,0xb8800105,0xb8c00105,0xb9000105,0xb9400105,0xb9800105,0xb9c00105 + .long 0xba000105,0xba400105,0xba800105,0xbac00105,0xbb000105,0xbb400105,0xbb800105,0xbbc00105 + .long 0xbc000105,0xbc400105,0xbc800105,0xbcc00105,0xbd000105,0xbd400105,0xbd800105,0xbdc00105 + .long 0xbe000105,0xbe400105,0xbe800105,0xbec00105,0xbf000105,0xbf400105,0xbf800105,0xbfc00105 + .long 0xc0000105,0xc0400105,0xc0800105,0xc0c00105,0xc1000105,0xc1400105,0xc1800105,0xc1c00105 + .long 0xc2000105,0xc2400105,0xc2800105,0xc2c00105,0xc3000105,0xc3400105,0xc3800105,0xc3c00105 + .long 0xc4000105,0xc4400105,0xc4800105,0xc4c00105,0xc5000105,0xc5400105,0xc5800105,0xc5c00105 + .long 0xc6000105,0xc6400105,0xc6800105,0xc6c00105,0xc7000105,0xc7400105,0xc7800105,0xc7c00105 + .long 0xc8000105,0xc8400105,0xc8800105,0xc8c00105,0xc9000105,0xc9400105,0xc9800105,0xc9c00105 + .long 0xca000105,0xca400105,0xca800105,0xcac00105,0xcb000105,0xcb400105,0xcb800105,0xcbc00105 + .long 0xcc000105,0xcc400105,0xcc800105,0xccc00105,0xcd000105,0xcd400105,0xcd800105,0xcdc00105 + .long 0xce000105,0xce400105,0xce800105,0xcec00105,0xcf000105,0xcf400105,0xcf800105,0xcfc00105 + .long 0xd0000105,0xd0400105,0xd0800105,0xd0c00105,0xd1000105,0xd1400105,0xd1800105,0xd1c00105 + .long 0xd2000105,0xd2400105,0xd2800105,0xd2c00105,0xd3000105,0xd3400105,0xd3800105,0xd3c00105 + .long 0xd4000105,0xd4400105,0xd4800105,0xd4c00105,0xd5000105,0xd5400105,0xd5800105,0xd5c00105 + .long 0xd6000105,0xd6400105,0xd6800105,0xd6c00105,0xd7000105,0xd7400105,0xd7800105,0xd7c00105 + .long 0xd8000105,0xd8400105,0xd8800105,0xd8c00105,0xd9000105,0xd9400105,0xd9800105,0xd9c00105 + .long 0xda000105,0xda400105,0xda800105,0xdac00105,0xdb000105,0xdb400105,0xdb800105,0xdbc00105 + .long 0xdc000105,0xdc400105,0xdc800105,0xdcc00105,0xdd000105,0xdd400105,0xdd800105,0xddc00105 + .long 0xde000105,0xde400105,0xde800105,0xdec00105,0xdf000105,0xdf400105,0xdf800105,0xdfc00105 + .long 0xe0000105,0xe0400105,0xe0800105,0xe0c00105,0xe1000105,0xe1400105,0xe1800105,0xe1c00105 + .long 0xe2000105,0xe2400105,0xe2800105,0xe2c00105,0xe3000105,0xe3400105,0xe3800105,0xe3c00105 + .long 0xe4000105,0xe4400105,0xe4800105,0xe4c00105,0xe5000105,0xe5400105,0xe5800105,0xe5c00105 + .long 0xe6000105,0xe6400105,0xe6800105,0xe6c00105,0xe7000105,0xe7400105,0xe7800105,0xe7c00105 + .long 0xe8000105,0xe8400105,0xe8800105,0xe8c00105,0xe9000105,0xe9400105,0xe9800105,0xe9c00105 + .long 0xea000105,0xea400105,0xea800105,0xeac00105,0xeb000105,0xeb400105,0xeb800105,0xebc00105 + .long 0xec000105,0xec400105,0xec800105,0xecc00105,0xed000105,0xed400105,0xed800105,0xedc00105 + .long 0xee000105,0xee400105,0xee800105,0xeec00105,0xef000105,0xef400105,0xef800105,0xefc00105 + .long 0xf0000105,0xf0400105,0xf0800105,0xf0c00105,0xf1000105,0xf1400105,0xf1800105,0xf1c00105 + .long 0xf2000105,0xf2400105,0xf2800105,0xf2c00105,0xf3000105,0xf3400105,0xf3800105,0xf3c00105 + .long 0xf4000105,0xf4400105,0xf4800105,0xf4c00105,0xf5000105,0xf5400105,0xf5800105,0xf5c00105 + .long 0xf6000105,0xf6400105,0xf6800105,0xf6c00105,0xf7000105,0xf7400105,0xf7800105,0xf7c00105 + .long 0xf8000105,0xf8400105,0xf8800105,0xf8c00105,0xf9000105,0xf9400105,0xf9800105,0xf9c00105 + .long 0xfa000105,0xfa400105,0xfa800105,0xfac00105,0xfb000105,0xfb400105,0xfb800105,0xfbc00105 + .long 0xfc000105,0xfc400105,0xfc800105,0xfcc00105,0xfd000105,0xfd400105,0xfd800105,0xfdc00105 + .long 0xfe000105,0xfe400105,0xfe800105,0xfec00105,0xff000105,0xff400105,0xff800105,0xffc00105