diff options
| -rw-r--r-- | sys/amd64/amd64/machdep.c | 78 | ||||
| -rw-r--r-- | sys/i386/i386/machdep.c | 78 |
2 files changed, 96 insertions, 60 deletions
diff --git a/sys/amd64/amd64/machdep.c b/sys/amd64/amd64/machdep.c index 69190b7..6e771c7 100644 --- a/sys/amd64/amd64/machdep.c +++ b/sys/amd64/amd64/machdep.c @@ -35,7 +35,7 @@ * SUCH DAMAGE. * * from: @(#)machdep.c 7.4 (Berkeley) 6/3/91 - * $Id: machdep.c,v 1.199 1996/08/19 20:06:52 julian Exp $ + * $Id: machdep.c,v 1.200 1996/09/01 02:16:07 nate Exp $ */ #include "npx.h" @@ -1081,39 +1081,64 @@ init386(first) biosextmem = rtcin(RTC_EXTLO)+ (rtcin(RTC_EXTHI)<<8); /* - * Print a warning and set it to the safest value if the official - * BIOS interface (bootblock supplied) disagrees with the - * hackish interface used above. Eventually only the official - * interface should be used. This is necessary for some machines - * who 'steal' memory from the basemem for use as BIOS memory. + * If BIOS tells us that it has more than 640k in the basemem, + * don't believe it - set it to 640k. + */ + if (biosbasemem > 640) { + printf("Preposterous RTC basemem of %dK, truncating to 640K\n", + biosbasemem); + biosbasemem = 640; + } + if (bootinfo.bi_memsizes_valid && bootinfo.bi_basemem > 640) { + printf("Preposterous BIOS basemem of %dK, truncating to 640K\n", + bootinfo.bi_basemem); + bootinfo.bi_basemem = 640; + } + + /* + * Warn if the official BIOS interface disagrees with the RTC + * interface used above about the amount of base memory or the + * amount of extended memory. Prefer the BIOS value for the base + * memory. This is necessary for machines that `steal' base + * memory for use as BIOS memory, at least if we are going to use + * the BIOS for apm. Prefer the RTC value for extended memory. + * Eventually the hackish interface shouldn't even be looked at. */ if (bootinfo.bi_memsizes_valid) { if (bootinfo.bi_basemem != biosbasemem) { - vm_offset_t pa, va, tmpva; - vm_size_t size; - unsigned *pte; + vm_offset_t pa; - printf("BIOS basemem (%ldK) != RTC basemem (%dK), ", + printf( + "BIOS basemem (%ldK) != RTC basemem (%dK), setting to BIOS value\n", bootinfo.bi_basemem, biosbasemem); - printf("setting to BIOS value.\n"); biosbasemem = bootinfo.bi_basemem; + /* - * XXX - Map this 'hole' of memory in the same manner - * as the ISA_HOLE (read/write/non-cacheable), since - * the BIOS 'fudges' it to become part of the ISA_HOLE. + * XXX if biosbasemem is now < 640, there is `hole' + * between the end of base memory and the start of + * ISA memory. The hole may be empty or it may + * contain BIOS code or data. Map it read/write so + * that the BIOS can write to it. (Memory from 0 to + * the physical end of the kernel is mapped read-only + * to begin with and then parts of it are remapped. + * The parts that aren't remapped form holes that + * remain read-only and are unused by the kernel. + * The base memory area is below the physical end of + * the kernel and right now forms a read-only hole. + * The part of it from 0 to + * (trunc_page(biosbasemem * 1024) - 1) will be + * remapped and used by the kernel later.) + * * This code is similar to the code used in * pmap_mapdev, but since no memory needs to be * allocated we simply change the mapping. */ - pa = biosbasemem * 1024; - va = pa + KERNBASE; - size = roundup(ISA_HOLE_START - pa, PAGE_SIZE); - for (tmpva = va; size > 0;) { - pte = (unsigned *)vtopte(tmpva); - *pte = pa | PG_RW | PG_V | PG_N; - size -= PAGE_SIZE; - tmpva += PAGE_SIZE; - pa += PAGE_SIZE; + for (pa = trunc_page(biosbasemem * 1024); + pa < ISA_HOLE_START; pa += PAGE_SIZE) { + unsigned *pte; + + pte = (unsigned *)vtopte(pa + KERNBASE); + *pte = pa | PG_RW | PG_V; } } if (bootinfo.bi_extmem != biosextmem) @@ -1122,13 +1147,6 @@ init386(first) } /* - * If BIOS tells us that it has more than 640k in the basemem, - * don't believe it - set it to 640k. - */ - if (biosbasemem > 640) - biosbasemem = 640; - - /* * Some 386 machines might give us a bogus number for extended * mem. If this happens, stop now. */ diff --git a/sys/i386/i386/machdep.c b/sys/i386/i386/machdep.c index 69190b7..6e771c7 100644 --- a/sys/i386/i386/machdep.c +++ b/sys/i386/i386/machdep.c @@ -35,7 +35,7 @@ * SUCH DAMAGE. * * from: @(#)machdep.c 7.4 (Berkeley) 6/3/91 - * $Id: machdep.c,v 1.199 1996/08/19 20:06:52 julian Exp $ + * $Id: machdep.c,v 1.200 1996/09/01 02:16:07 nate Exp $ */ #include "npx.h" @@ -1081,39 +1081,64 @@ init386(first) biosextmem = rtcin(RTC_EXTLO)+ (rtcin(RTC_EXTHI)<<8); /* - * Print a warning and set it to the safest value if the official - * BIOS interface (bootblock supplied) disagrees with the - * hackish interface used above. Eventually only the official - * interface should be used. This is necessary for some machines - * who 'steal' memory from the basemem for use as BIOS memory. + * If BIOS tells us that it has more than 640k in the basemem, + * don't believe it - set it to 640k. + */ + if (biosbasemem > 640) { + printf("Preposterous RTC basemem of %dK, truncating to 640K\n", + biosbasemem); + biosbasemem = 640; + } + if (bootinfo.bi_memsizes_valid && bootinfo.bi_basemem > 640) { + printf("Preposterous BIOS basemem of %dK, truncating to 640K\n", + bootinfo.bi_basemem); + bootinfo.bi_basemem = 640; + } + + /* + * Warn if the official BIOS interface disagrees with the RTC + * interface used above about the amount of base memory or the + * amount of extended memory. Prefer the BIOS value for the base + * memory. This is necessary for machines that `steal' base + * memory for use as BIOS memory, at least if we are going to use + * the BIOS for apm. Prefer the RTC value for extended memory. + * Eventually the hackish interface shouldn't even be looked at. */ if (bootinfo.bi_memsizes_valid) { if (bootinfo.bi_basemem != biosbasemem) { - vm_offset_t pa, va, tmpva; - vm_size_t size; - unsigned *pte; + vm_offset_t pa; - printf("BIOS basemem (%ldK) != RTC basemem (%dK), ", + printf( + "BIOS basemem (%ldK) != RTC basemem (%dK), setting to BIOS value\n", bootinfo.bi_basemem, biosbasemem); - printf("setting to BIOS value.\n"); biosbasemem = bootinfo.bi_basemem; + /* - * XXX - Map this 'hole' of memory in the same manner - * as the ISA_HOLE (read/write/non-cacheable), since - * the BIOS 'fudges' it to become part of the ISA_HOLE. + * XXX if biosbasemem is now < 640, there is `hole' + * between the end of base memory and the start of + * ISA memory. The hole may be empty or it may + * contain BIOS code or data. Map it read/write so + * that the BIOS can write to it. (Memory from 0 to + * the physical end of the kernel is mapped read-only + * to begin with and then parts of it are remapped. + * The parts that aren't remapped form holes that + * remain read-only and are unused by the kernel. + * The base memory area is below the physical end of + * the kernel and right now forms a read-only hole. + * The part of it from 0 to + * (trunc_page(biosbasemem * 1024) - 1) will be + * remapped and used by the kernel later.) + * * This code is similar to the code used in * pmap_mapdev, but since no memory needs to be * allocated we simply change the mapping. */ - pa = biosbasemem * 1024; - va = pa + KERNBASE; - size = roundup(ISA_HOLE_START - pa, PAGE_SIZE); - for (tmpva = va; size > 0;) { - pte = (unsigned *)vtopte(tmpva); - *pte = pa | PG_RW | PG_V | PG_N; - size -= PAGE_SIZE; - tmpva += PAGE_SIZE; - pa += PAGE_SIZE; + for (pa = trunc_page(biosbasemem * 1024); + pa < ISA_HOLE_START; pa += PAGE_SIZE) { + unsigned *pte; + + pte = (unsigned *)vtopte(pa + KERNBASE); + *pte = pa | PG_RW | PG_V; } } if (bootinfo.bi_extmem != biosextmem) @@ -1122,13 +1147,6 @@ init386(first) } /* - * If BIOS tells us that it has more than 640k in the basemem, - * don't believe it - set it to 640k. - */ - if (biosbasemem > 640) - biosbasemem = 640; - - /* * Some 386 machines might give us a bogus number for extended * mem. If this happens, stop now. */ |
