linux/arch/x86/include/asm/olpc_ofw.h
Andres Salomon c10d1e260f x86, olpc: Add OLPC device-tree support
Make use of PROC_DEVICETREE to export the tree, and sparc's PROMTREE code to
call into OLPC's Open Firmware to build the tree.

v5: fix buglet with root node check (introduced in v4)

v4: address some minor style issues pointed out by Grant, and explicitly cast
    negative phandle checks to s32.

v3: rename olpc_prom to olpc_dt
  - rework Kconfig entries
  - drop devtree build hook from proc, instead adding a call to x86's
    paging_init (similarly to how sparc64 does it)
  - switch allocation from using slab to alloc_bootmem.  this allows
    the DT to be built earlier during boot (during setup_arch); the
    downside is that there are some 1200 bootmem reservations that are
    done during boot.  Not ideal..
  - add a helper olpc_ofw_is_installed function to test for the
    existence and successful detection of OLPC's OFW.

Signed-off-by: Andres Salomon <dilinger@queued.net>
LKML-Reference: <20101116220952.26526a80@queued.net>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2010-12-15 17:11:30 -08:00

45 lines
1.3 KiB
C

#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
extern bool olpc_ofw_is_installed(void);
/* 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, const 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);
/* check if OFW was detected during boot */
extern bool olpc_ofw_present(void);
#else /* !CONFIG_OLPC_OPENFIRMWARE */
static inline bool olpc_ofw_is_installed(void) { return false; }
static inline void olpc_ofw_detect(void) { }
static inline void setup_olpc_ofw_pgd(void) { }
static inline bool olpc_ofw_present(void) { return false; }
#endif /* !CONFIG_OLPC_OPENFIRMWARE */
#ifdef CONFIG_OLPC_OPENFIRMWARE_DT
extern void olpc_dt_build_devicetree(void);
#else
static inline void olpc_dt_build_devicetree(void) { }
#endif /* CONFIG_OLPC_OPENFIRMWARE_DT */
#endif /* _ASM_X86_OLPC_OFW_H */