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Change method to determine base memory size.

Browse Source 
Try INT 15H/E820H first, then fall back to the old compatibility
method (INT 12H).
This is a workaround for newer machines which have broken INT 12H BIOS
service implementation.

Reviewed by:	-current ML
MFC after:	3 days
This commit is contained in:
Mitsuru IWASAKI 2002-10-25 18:46:36 +00:00
parent df6b615a42
commit fb3a308a4a
2 changed files with 110 additions and 86 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

98
sys/amd64/amd64/machdep.c
View File

@ -1281,49 +1281,7 @@ getmemsize(int first)
bzero(&vmf, sizeof(struct vm86frame));
bzero(physmap, sizeof(physmap));
/*
* Perform "base memory" related probes & setup
*/
vm86_intcall(0x12, &vmf);
basemem = vmf.vmf_ax;
if (basemem > 640) {
printf("Preposterous BIOS basemem of %uK, truncating to 640K\n",
basemem);
basemem = 640;
}
/*
* XXX if biosbasemem is now < 640, there is a `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 PAGE_SIZE 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.
*/
for (pa = trunc_page(basemem * 1024);
pa < ISA_HOLE_START; pa += PAGE_SIZE)
pmap_kenter(KERNBASE + pa, pa);
/*
* if basemem != 640, map pages r/w into vm86 page table so
* that the bios can scribble on it.
*/
pte = (pt_entry_t *)vm86paddr;
for (i = basemem / 4; i < 160; i++)
pte[i] = (i << PAGE_SHIFT) | PG_V | PG_RW | PG_U;
basemem = 0;
/*
* map page 1 R/W into the kernel page table so we can use it
@ -1392,6 +1350,60 @@ getmemsize(int first)
next_run: ;
} while (vmf.vmf_ebx != 0);
/*
* Perform "base memory" related probes & setup
*/
for (i = 0; i <= physmap_idx; i += 2) {
if (physmap[i] == 0x00000000) {
basemem = physmap[i + 1] / 1024;
break;
}
}
/* Fall back to the old compatibility function for base memory */
if (basemem == 0) {
vm86_intcall(0x12, &vmf);
basemem = vmf.vmf_ax;
}
if (basemem > 640) {
printf("Preposterous BIOS basemem of %uK, truncating to 640K\n",
basemem);
basemem = 640;
}
/*
* XXX if biosbasemem is now < 640, there is a `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 PAGE_SIZE 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.
*/
for (pa = trunc_page(basemem * 1024);
pa < ISA_HOLE_START; pa += PAGE_SIZE)
pmap_kenter(KERNBASE + pa, pa);
/*
* if basemem != 640, map pages r/w into vm86 page table so
* that the bios can scribble on it.
*/
pte = (pt_entry_t *)vm86paddr;
for (i = basemem / 4; i < 160; i++)
pte[i] = (i << PAGE_SHIFT) | PG_V | PG_RW | PG_U;
if (physmap[1] != 0)
goto physmap_done;

98
sys/i386/i386/machdep.c
View File

@ -1281,49 +1281,7 @@ getmemsize(int first)
bzero(&vmf, sizeof(struct vm86frame));
bzero(physmap, sizeof(physmap));
/*
* Perform "base memory" related probes & setup
*/
vm86_intcall(0x12, &vmf);
basemem = vmf.vmf_ax;
if (basemem > 640) {
printf("Preposterous BIOS basemem of %uK, truncating to 640K\n",
basemem);
basemem = 640;
}
/*
* XXX if biosbasemem is now < 640, there is a `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 PAGE_SIZE 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.
*/
for (pa = trunc_page(basemem * 1024);
pa < ISA_HOLE_START; pa += PAGE_SIZE)
pmap_kenter(KERNBASE + pa, pa);
/*
* if basemem != 640, map pages r/w into vm86 page table so
* that the bios can scribble on it.
*/
pte = (pt_entry_t *)vm86paddr;
for (i = basemem / 4; i < 160; i++)
pte[i] = (i << PAGE_SHIFT) | PG_V | PG_RW | PG_U;
basemem = 0;
/*
* map page 1 R/W into the kernel page table so we can use it
@ -1392,6 +1350,60 @@ getmemsize(int first)
next_run: ;
} while (vmf.vmf_ebx != 0);
/*
* Perform "base memory" related probes & setup
*/
for (i = 0; i <= physmap_idx; i += 2) {
if (physmap[i] == 0x00000000) {
basemem = physmap[i + 1] / 1024;
break;
}
}
/* Fall back to the old compatibility function for base memory */
if (basemem == 0) {
vm86_intcall(0x12, &vmf);
basemem = vmf.vmf_ax;
}
if (basemem > 640) {
printf("Preposterous BIOS basemem of %uK, truncating to 640K\n",
basemem);
basemem = 640;
}
/*
* XXX if biosbasemem is now < 640, there is a `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 PAGE_SIZE 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.
*/
for (pa = trunc_page(basemem * 1024);
pa < ISA_HOLE_START; pa += PAGE_SIZE)
pmap_kenter(KERNBASE + pa, pa);
/*
* if basemem != 640, map pages r/w into vm86 page table so
* that the bios can scribble on it.
*/
pte = (pt_entry_t *)vm86paddr;
for (i = basemem / 4; i < 160; i++)
pte[i] = (i << PAGE_SHIFT) | PG_V | PG_RW | PG_U;
if (physmap[1] != 0)
goto physmap_done;