diff options
| author | Andres Salomon <dilinger@queued.net> | 2010-06-19 01:46:53 +0400 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2010-06-19 01:54:36 +0400 |
| commit | fd699c76552bbfa66631f019be415a87dbb08237 (patch) | |
| tree | 49f136f22fc94230af214f9c9c21a6fc0b7180e1 /arch/x86/include | |
| parent | 7e27d6e778cd87b6f2415515d7127eba53fe5d02 (diff) | |
| download | linux-fd699c76552bbfa66631f019be415a87dbb08237.tar.xz | |
x86, olpc: Add support for calling into OpenFirmware
Add support for saving OFW's cif, and later calling into it to run OFW
commands. OFW remains resident in memory, living within virtual range
0xff800000 - 0xffc00000. A single page directory entry points to the
pgdir that OFW actually uses, so rather than saving the entire page
table, we grab and install that one entry permanently in the kernel's
page table.
This is currently only used by the OLPC XO. Note that this particular
calling convention breaks PAE and PAT, and so cannot be used on newer
x86 hardware.
Signed-off-by: Andres Salomon <dilinger@queued.net>
LKML-Reference: <20100618174653.7755a39a@dev.queued.net>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'arch/x86/include')
| -rw-r--r-- | arch/x86/include/asm/bootparam.h | 11 | ||||
| -rw-r--r-- | arch/x86/include/asm/olpc_ofw.h | 31 |
2 files changed, 41 insertions, 1 deletions
diff --git a/arch/x86/include/asm/bootparam.h b/arch/x86/include/asm/bootparam.h index 6be33d83c716..8e6218550e77 100644 --- a/arch/x86/include/asm/bootparam.h +++ b/arch/x86/include/asm/bootparam.h @@ -70,6 +70,14 @@ struct sys_desc_table { __u8 table[14]; }; +/* Gleaned from OFW's set-parameters in cpu/x86/pc/linux.fth */ +struct olpc_ofw_header { + __u32 ofw_magic; /* OFW signature */ + __u32 ofw_version; + __u32 cif_handler; /* callback into OFW */ + __u32 irq_desc_table; +} __attribute__((packed)); + struct efi_info { __u32 efi_loader_signature; __u32 efi_systab; @@ -92,7 +100,8 @@ struct boot_params { __u8 hd0_info[16]; /* obsolete! */ /* 0x080 */ __u8 hd1_info[16]; /* obsolete! */ /* 0x090 */ struct sys_desc_table sys_desc_table; /* 0x0a0 */ - __u8 _pad4[144]; /* 0x0b0 */ + struct olpc_ofw_header olpc_ofw_header; /* 0x0b0 */ + __u8 _pad4[128]; /* 0x0c0 */ struct edid_info edid_info; /* 0x140 */ struct efi_info efi_info; /* 0x1c0 */ __u32 alt_mem_k; /* 0x1e0 */ diff --git a/arch/x86/include/asm/olpc_ofw.h b/arch/x86/include/asm/olpc_ofw.h new file mode 100644 index 000000000000..3e63d857c48f --- /dev/null +++ b/arch/x86/include/asm/olpc_ofw.h @@ -0,0 +1,31 @@ +#ifndef _ASM_X86_OLPC_OFW_H +#define _ASM_X86_OLPC_OFW_H + +/* index into the page table containing the entry OFW occupies */ +#define OLPC_OFW_PDE_NR 1022 + +#define OLPC_OFW_SIG 0x2057464F /* aka "OFW " */ + +#ifdef CONFIG_OLPC_OPENFIRMWARE + +/* run an OFW command by calling into the firmware */ +#define olpc_ofw(name, args, res) \ + __olpc_ofw((name), ARRAY_SIZE(args), args, ARRAY_SIZE(res), res) + +extern int __olpc_ofw(const char *name, int nr_args, void **args, int nr_res, + void **res); + +/* determine whether OFW is available and lives in the proper memory */ +extern void olpc_ofw_detect(void); + +/* install OFW's pde permanently into the kernel's pgtable */ +extern void setup_olpc_ofw_pgd(void); + +#else /* !CONFIG_OLPC_OPENFIRMWARE */ + +static inline void olpc_ofw_detect(void) { } +static inline void setup_olpc_ofw_pgd(void) { } + +#endif /* !CONFIG_OLPC_OPENFIRMWARE */ + +#endif /* _ASM_X86_OLPC_OFW_H */ |