From c10d1e260f7cb6766dc76b4e36ed8f4be53f195a Mon Sep 17 00:00:00 2001 From: Andres Salomon Date: Wed, 17 Nov 2010 06:09:52 +0000 Subject: [PATCH] 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 LKML-Reference: <20101116220952.26526a80@queued.net> Signed-off-by: H. Peter Anvin --- arch/x86/Kconfig | 6 ++ arch/x86/include/asm/olpc_ofw.h | 9 +++ arch/x86/include/asm/prom.h | 1 + arch/x86/mm/init_32.c | 2 + arch/x86/platform/olpc/Makefile | 1 + arch/x86/platform/olpc/olpc_dt.c | 165 ++++++++++++++++++++++++++++++++++++++ arch/x86/platform/olpc/olpc_ofw.c | 5 ++ 7 files changed, 189 insertions(+) create mode 100644 arch/x86/include/asm/prom.h create mode 100644 arch/x86/platform/olpc/olpc_dt.c diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index e330da2..ef34031 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -2049,11 +2049,17 @@ config OLPC_OPENFIRMWARE bool "Support for OLPC's Open Firmware" depends on !X86_64 && !X86_PAE default n + select OF help This option adds support for the implementation of Open Firmware that is used on the OLPC XO-1 Children's Machine. If unsure, say N here. +config OLPC_OPENFIRMWARE_DT + bool + default y if OLPC_OPENFIRMWARE && PROC_DEVICETREE + select OF_PROMTREE + endif # X86_32 config AMD_NB diff --git a/arch/x86/include/asm/olpc_ofw.h b/arch/x86/include/asm/olpc_ofw.h index 2a84781..641988e 100644 --- a/arch/x86/include/asm/olpc_ofw.h +++ b/arch/x86/include/asm/olpc_ofw.h @@ -8,6 +8,8 @@ #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) @@ -26,10 +28,17 @@ 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 */ diff --git a/arch/x86/include/asm/prom.h b/arch/x86/include/asm/prom.h new file mode 100644 index 0000000..b4ec95f --- /dev/null +++ b/arch/x86/include/asm/prom.h @@ -0,0 +1 @@ +/* dummy prom.h; here to make linux/of.h's #includes happy */ diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c index 0e969f9..8c852e4 100644 --- a/arch/x86/mm/init_32.c +++ b/arch/x86/mm/init_32.c @@ -45,6 +45,7 @@ #include #include #include +#include #include #include #include @@ -715,6 +716,7 @@ void __init paging_init(void) /* * NOTE: at this point the bootmem allocator is fully available. */ + olpc_dt_build_devicetree(); sparse_init(); zone_sizes_init(); } diff --git a/arch/x86/platform/olpc/Makefile b/arch/x86/platform/olpc/Makefile index c31b8fc..e797428 100644 --- a/arch/x86/platform/olpc/Makefile +++ b/arch/x86/platform/olpc/Makefile @@ -1,3 +1,4 @@ obj-$(CONFIG_OLPC) += olpc.o obj-$(CONFIG_OLPC_XO1) += olpc-xo1.o obj-$(CONFIG_OLPC_OPENFIRMWARE) += olpc_ofw.o +obj-$(CONFIG_OLPC_OPENFIRMWARE_DT) += olpc_dt.o diff --git a/arch/x86/platform/olpc/olpc_dt.c b/arch/x86/platform/olpc/olpc_dt.c new file mode 100644 index 0000000..7054697 --- /dev/null +++ b/arch/x86/platform/olpc/olpc_dt.c @@ -0,0 +1,165 @@ +/* + * OLPC-specific OFW device tree support code. + * + * Paul Mackerras August 1996. + * Copyright (C) 1996-2005 Paul Mackerras. + * + * Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner. + * {engebret|bergner}@us.ibm.com + * + * Adapted for sparc by David S. Miller davem@davemloft.net + * Adapted for x86/OLPC by Andres Salomon + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include +#include +#include +#include +#include + +static phandle __init olpc_dt_getsibling(phandle node) +{ + const void *args[] = { (void *)node }; + void *res[] = { &node }; + + if ((s32)node == -1) + return 0; + + if (olpc_ofw("peer", args, res) || (s32)node == -1) + return 0; + + return node; +} + +static phandle __init olpc_dt_getchild(phandle node) +{ + const void *args[] = { (void *)node }; + void *res[] = { &node }; + + if ((s32)node == -1) + return 0; + + if (olpc_ofw("child", args, res) || (s32)node == -1) { + pr_err("PROM: %s: fetching child failed!\n", __func__); + return 0; + } + + return node; +} + +static int __init olpc_dt_getproplen(phandle node, const char *prop) +{ + const void *args[] = { (void *)node, prop }; + int len; + void *res[] = { &len }; + + if ((s32)node == -1) + return -1; + + if (olpc_ofw("getproplen", args, res)) { + pr_err("PROM: %s: getproplen failed!\n", __func__); + return -1; + } + + return len; +} + +static int __init olpc_dt_getproperty(phandle node, const char *prop, + char *buf, int bufsize) +{ + int plen; + + plen = olpc_dt_getproplen(node, prop); + if (plen > bufsize || plen < 1) { + return -1; + } else { + const void *args[] = { (void *)node, prop, buf, (void *)plen }; + void *res[] = { &plen }; + + if (olpc_ofw("getprop", args, res)) { + pr_err("PROM: %s: getprop failed!\n", __func__); + return -1; + } + } + + return plen; +} + +static int __init olpc_dt_nextprop(phandle node, char *prev, char *buf) +{ + const void *args[] = { (void *)node, prev, buf }; + int success; + void *res[] = { &success }; + + buf[0] = '\0'; + + if ((s32)node == -1) + return -1; + + if (olpc_ofw("nextprop", args, res) || success != 1) + return -1; + + return 0; +} + +static int __init olpc_dt_pkg2path(phandle node, char *buf, + const int buflen, int *len) +{ + const void *args[] = { (void *)node, buf, (void *)buflen }; + void *res[] = { len }; + + if ((s32)node == -1) + return -1; + + if (olpc_ofw("package-to-path", args, res) || *len < 1) + return -1; + + return 0; +} + +static unsigned int prom_early_allocated __initdata; + +void * __init prom_early_alloc(unsigned long size) +{ + void *res; + + res = alloc_bootmem(size); + if (res) + memset(res, 0, size); + + prom_early_allocated += size; + + return res; +} + +static struct of_pdt_ops prom_olpc_ops __initdata = { + .nextprop = olpc_dt_nextprop, + .getproplen = olpc_dt_getproplen, + .getproperty = olpc_dt_getproperty, + .getchild = olpc_dt_getchild, + .getsibling = olpc_dt_getsibling, + .pkg2path = olpc_dt_pkg2path, +}; + +void __init olpc_dt_build_devicetree(void) +{ + phandle root; + + if (!olpc_ofw_is_installed()) + return; + + root = olpc_dt_getsibling(0); + if (!root) { + pr_err("PROM: unable to get root node from OFW!\n"); + return; + } + of_pdt_build_devicetree(root, &prom_olpc_ops); + + pr_info("PROM DT: Built device tree with %u bytes of memory.\n", + prom_early_allocated); +} diff --git a/arch/x86/platform/olpc/olpc_ofw.c b/arch/x86/platform/olpc/olpc_ofw.c index 7873204..e7604f6 100644 --- a/arch/x86/platform/olpc/olpc_ofw.c +++ b/arch/x86/platform/olpc/olpc_ofw.c @@ -110,3 +110,8 @@ void __init olpc_ofw_detect(void) (unsigned long)olpc_ofw_cif, (-start) >> 20); reserve_top_address(-start); } + +bool __init olpc_ofw_is_installed(void) +{ + return olpc_ofw_cif != NULL; +} -- 2.7.4