Use the correct location of the EBDA for searching for the RSDP.
The EBDA is the 1 KB area addressed by the 16 bit pointer at 0x40E. Pointed out by: robert.moore AT intel.com
This commit is contained in:
parent
3ffbc0cd8e
commit
2c0d74e8e8
Notes:
svn2git
2020-12-20 02:59:44 +00:00
svn path=/head/; revision=129702
@ -84,22 +84,24 @@ biosacpi_detect(void)
|
||||
}
|
||||
|
||||
/*
|
||||
* Find the RSDP in low memory.
|
||||
* Find the RSDP in low memory. See section 5.2.2 of the ACPI spec.
|
||||
*/
|
||||
static RSDP_DESCRIPTOR *
|
||||
biosacpi_find_rsdp(void)
|
||||
{
|
||||
RSDP_DESCRIPTOR *rsdp;
|
||||
uint16_t *addr;
|
||||
|
||||
/* search the EBDA */
|
||||
if ((rsdp = biosacpi_search_rsdp((char *)0, 0x400)) != NULL)
|
||||
return(rsdp);
|
||||
/* EBDA is the 1 KB addressed by the 16 bit pointer at 0x40E. */
|
||||
addr = (uint16_t *)0x40E;
|
||||
if ((rsdp = biosacpi_search_rsdp((char *)(*addr << 4), 0x400)) != NULL)
|
||||
return (rsdp);
|
||||
|
||||
/* search the BIOS space */
|
||||
/* Check the upper memory BIOS space, 0xe0000 - 0xfffff. */
|
||||
if ((rsdp = biosacpi_search_rsdp((char *)0xe0000, 0x20000)) != NULL)
|
||||
return(rsdp);
|
||||
return (rsdp);
|
||||
|
||||
return(NULL);
|
||||
return (NULL);
|
||||
}
|
||||
|
||||
static RSDP_DESCRIPTOR *
|
||||
|
@ -121,6 +121,34 @@ acpi_get_rsdp(u_long addr)
|
||||
return (acpi_map_physical(addr, len));
|
||||
}
|
||||
|
||||
static struct ACPIrsdp *
|
||||
acpi_scan_rsd_ptr(void)
|
||||
{
|
||||
#if defined(__i386__)
|
||||
struct ACPIrsdp *rsdp;
|
||||
u_long addr, end;
|
||||
|
||||
/*
|
||||
* On ia32, scan physical memory for the RSD PTR if above failed.
|
||||
* According to section 5.2.2 of the ACPI spec, we only consider
|
||||
* two regions for the base address:
|
||||
* 1. EBDA (1 KB area addressed by the 16 bit pointer at 0x40E
|
||||
* 2. High memory (0xE0000 - 0xFFFFF)
|
||||
*/
|
||||
addr = RSDP_EBDA_PTR;
|
||||
pread(acpi_mem_fd, &addr, sizeof(uint16_t), addr);
|
||||
addr <<= 4;
|
||||
end = addr + RSDP_EBDA_SIZE;
|
||||
for (; addr < end; addr += 16)
|
||||
if ((rsdp = acpi_get_rsdp(addr)) != NULL)
|
||||
return (rsdp);
|
||||
for (addr = RSDP_HI_START; addr < RSDP_HI_END; addr += 16)
|
||||
if ((rsdp = acpi_get_rsdp(addr)) != NULL)
|
||||
return (rsdp);
|
||||
#endif /* __i386__ */
|
||||
return (NULL);
|
||||
}
|
||||
|
||||
/*
|
||||
* Public interfaces
|
||||
*/
|
||||
@ -143,23 +171,7 @@ acpi_find_rsd_ptr(void)
|
||||
machdep_acpi_root);
|
||||
}
|
||||
|
||||
#if defined(__i386__)
|
||||
/*
|
||||
* On ia32, scan physical memory for the RSD PTR if above failed.
|
||||
* According to section 5.2.2 of the ACPI spec, we only consider
|
||||
* two regions for the base address:
|
||||
* 1. EBDA (0x0 - 0x3FF)
|
||||
* 2. High memory (0xE0000 - 0xFFFFF)
|
||||
*/
|
||||
for (addr = RSDP_EBDA_START; addr < RSDP_EBDA_END; addr += 16)
|
||||
if ((rsdp = acpi_get_rsdp(addr)) != NULL)
|
||||
return (rsdp);
|
||||
for (addr = RSDP_HI_START; addr < RSDP_HI_END; addr += 16)
|
||||
if ((rsdp = acpi_get_rsdp(addr)) != NULL)
|
||||
return (rsdp);
|
||||
#endif
|
||||
|
||||
return (NULL);
|
||||
return (acpi_scan_rsd_ptr());
|
||||
}
|
||||
|
||||
void *
|
||||
|
@ -299,8 +299,8 @@ struct ECDTbody {
|
||||
* 1. EBDA (0x0 - 0x3FF)
|
||||
* 2. High memory (0xE0000 - 0xFFFFF)
|
||||
*/
|
||||
#define RSDP_EBDA_START 0
|
||||
#define RSDP_EBDA_END (0x400 - sizeof(struct ACPIrsdp))
|
||||
#define RSDP_EBDA_PTR 0x40E
|
||||
#define RSDP_EBDA_SIZE (1024 - sizeof(struct ACPIrsdp))
|
||||
#define RSDP_HI_START 0xE0000
|
||||
#define RSDP_HI_END (0x100000 - sizeof(struct ACPIrsdp))
|
||||
|
||||
|
Loading…
Reference in New Issue
Block a user