diff options
| -rw-r--r-- | common/fdt_support.c | 264 | ||||
| -rw-r--r-- | include/fdt_support.h | 1 |
2 files changed, 265 insertions, 0 deletions
diff --git a/common/fdt_support.c b/common/fdt_support.c index 4d87135cb..70ad81d29 100644 --- a/common/fdt_support.c +++ b/common/fdt_support.c @@ -2,6 +2,8 @@ * (C) Copyright 2007 * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com * + * Copyright 2010 Freescale Semiconductor, Inc. + * * See file CREDITS for list of people who contributed to this * project. * @@ -861,3 +863,265 @@ void fdt_del_node_and_alias(void *blob, const char *alias) off = fdt_path_offset(blob, "/aliases"); fdt_delprop(blob, off, alias); } + +/* Helper to read a big number; size is in cells (not bytes) */ +static inline u64 of_read_number(const __be32 *cell, int size) +{ + u64 r = 0; + while (size--) + r = (r << 32) | be32_to_cpu(*(cell++)); + return r; +} + +static int of_n_cells(const void *blob, int nodeoffset, const char *name) +{ + int np; + const int *ip; + + do { + np = fdt_parent_offset(blob, nodeoffset); + + if (np >= 0) + nodeoffset = np; + ip = (int *)fdt_getprop(blob, nodeoffset, name, NULL); + if (ip) + return be32_to_cpup(ip); + } while (np >= 0); + + /* No #<NAME>-cells property for the root node */ + return 1; +} + +int of_n_addr_cells(const void *blob, int nodeoffset) +{ + return of_n_cells(blob, nodeoffset, "#address-cells"); +} + +int of_n_size_cells(const void *blob, int nodeoffset) +{ + return of_n_cells(blob, nodeoffset, "#size-cells"); +} + +#define PRu64 "%llx" + +/* Max address size we deal with */ +#define OF_MAX_ADDR_CELLS 4 +#define OF_BAD_ADDR ((u64)-1) +#define OF_CHECK_COUNTS(na, ns) ((na) > 0 && (na) <= OF_MAX_ADDR_CELLS && \ + (ns) > 0) + +/* Debug utility */ +#ifdef DEBUG +static void of_dump_addr(const char *s, const u32 *addr, int na) +{ + printf("%s", s); + while(na--) + printf(" %08x", *(addr++)); + printf("\n"); +} +#else +static void of_dump_addr(const char *s, const u32 *addr, int na) { } +#endif + +/* Callbacks for bus specific translators */ +struct of_bus { + const char *name; + const char *addresses; + void (*count_cells)(void *blob, int offset, + int *addrc, int *sizec); + u64 (*map)(u32 *addr, const u32 *range, + int na, int ns, int pna); + int (*translate)(u32 *addr, u64 offset, int na); +}; + +/* Default translator (generic bus) */ +static void of_bus_default_count_cells(void *blob, int offset, + int *addrc, int *sizec) +{ + if (addrc) + *addrc = of_n_addr_cells(blob, offset); + if (sizec) + *sizec = of_n_size_cells(blob, offset); +} + +static u64 of_bus_default_map(u32 *addr, const u32 *range, + int na, int ns, int pna) +{ + u64 cp, s, da; + + cp = of_read_number(range, na); + s = of_read_number(range + na + pna, ns); + da = of_read_number(addr, na); + + debug("OF: default map, cp="PRu64", s="PRu64", da="PRu64"\n", + cp, s, da); + + if (da < cp || da >= (cp + s)) + return OF_BAD_ADDR; + return da - cp; +} + +static int of_bus_default_translate(u32 *addr, u64 offset, int na) +{ + u64 a = of_read_number(addr, na); + memset(addr, 0, na * 4); + a += offset; + if (na > 1) + addr[na - 2] = a >> 32; + addr[na - 1] = a & 0xffffffffu; + + return 0; +} + +/* Array of bus specific translators */ +static struct of_bus of_busses[] = { + /* Default */ + { + .name = "default", + .addresses = "reg", + .count_cells = of_bus_default_count_cells, + .map = of_bus_default_map, + .translate = of_bus_default_translate, + }, +}; + +static int of_translate_one(void * blob, int parent, struct of_bus *bus, + struct of_bus *pbus, u32 *addr, + int na, int ns, int pna, const char *rprop) +{ + const u32 *ranges; + int rlen; + int rone; + u64 offset = OF_BAD_ADDR; + + /* Normally, an absence of a "ranges" property means we are + * crossing a non-translatable boundary, and thus the addresses + * below the current not cannot be converted to CPU physical ones. + * Unfortunately, while this is very clear in the spec, it's not + * what Apple understood, and they do have things like /uni-n or + * /ht nodes with no "ranges" property and a lot of perfectly + * useable mapped devices below them. Thus we treat the absence of + * "ranges" as equivalent to an empty "ranges" property which means + * a 1:1 translation at that level. It's up to the caller not to try + * to translate addresses that aren't supposed to be translated in + * the first place. --BenH. + */ + ranges = (u32 *)fdt_getprop(blob, parent, rprop, &rlen); + if (ranges == NULL || rlen == 0) { + offset = of_read_number(addr, na); + memset(addr, 0, pna * 4); + debug("OF: no ranges, 1:1 translation\n"); + goto finish; + } + + debug("OF: walking ranges...\n"); + + /* Now walk through the ranges */ + rlen /= 4; + rone = na + pna + ns; + for (; rlen >= rone; rlen -= rone, ranges += rone) { + offset = bus->map(addr, ranges, na, ns, pna); + if (offset != OF_BAD_ADDR) + break; + } + if (offset == OF_BAD_ADDR) { + debug("OF: not found !\n"); + return 1; + } + memcpy(addr, ranges + na, 4 * pna); + + finish: + of_dump_addr("OF: parent translation for:", addr, pna); + debug("OF: with offset: "PRu64"\n", offset); + + /* Translate it into parent bus space */ + return pbus->translate(addr, offset, pna); +} + +/* + * Translate an address from the device-tree into a CPU physical address, + * this walks up the tree and applies the various bus mappings on the + * way. + * + * Note: We consider that crossing any level with #size-cells == 0 to mean + * that translation is impossible (that is we are not dealing with a value + * that can be mapped to a cpu physical address). This is not really specified + * that way, but this is traditionally the way IBM at least do things + */ +u64 __of_translate_address(void *blob, int node_offset, const u32 *in_addr, + const char *rprop) +{ + int parent; + struct of_bus *bus, *pbus; + u32 addr[OF_MAX_ADDR_CELLS]; + int na, ns, pna, pns; + u64 result = OF_BAD_ADDR; + + debug("OF: ** translation for device %s **\n", + fdt_get_name(blob, node_offset, NULL)); + + /* Get parent & match bus type */ + parent = fdt_parent_offset(blob, node_offset); + if (parent < 0) + goto bail; + bus = &of_busses[0]; + + /* Cound address cells & copy address locally */ + bus->count_cells(blob, node_offset, &na, &ns); + if (!OF_CHECK_COUNTS(na, ns)) { + printf("%s: Bad cell count for %s\n", __FUNCTION__, + fdt_get_name(blob, node_offset, NULL)); + goto bail; + } + memcpy(addr, in_addr, na * 4); + + debug("OF: bus is %s (na=%d, ns=%d) on %s\n", + bus->name, na, ns, fdt_get_name(blob, parent, NULL)); + of_dump_addr("OF: translating address:", addr, na); + + /* Translate */ + for (;;) { + /* Switch to parent bus */ + node_offset = parent; + parent = fdt_parent_offset(blob, node_offset); + + /* If root, we have finished */ + if (parent < 0) { + debug("OF: reached root node\n"); + result = of_read_number(addr, na); + break; + } + + /* Get new parent bus and counts */ + pbus = &of_busses[0]; + pbus->count_cells(blob, node_offset, &pna, &pns); + if (!OF_CHECK_COUNTS(pna, pns)) { + printf("%s: Bad cell count for %s\n", __FUNCTION__, + fdt_get_name(blob, node_offset, NULL)); + break; + } + + debug("OF: parent bus is %s (na=%d, ns=%d) on %s\n", + pbus->name, pna, pns, fdt_get_name(blob, parent, NULL)); + + /* Apply bus translation */ + if (of_translate_one(blob, node_offset, bus, pbus, + addr, na, ns, pna, rprop)) + break; + + /* Complete the move up one level */ + na = pna; + ns = pns; + bus = pbus; + + of_dump_addr("OF: one level translation:", addr, na); + } + bail: + + return result; +} + +u64 fdt_translate_address(void *blob, int node_offset, const u32 *in_addr) +{ + return __of_translate_address(blob, node_offset, in_addr, "ranges"); +} diff --git a/include/fdt_support.h b/include/fdt_support.h index fc16159eb..78c38b296 100644 --- a/include/fdt_support.h +++ b/include/fdt_support.h @@ -83,6 +83,7 @@ int fdt_fixup_nor_flash_size(void *blob, int cs, u32 size); void fdt_fixup_mtdparts(void *fdt, void *node_info, int node_info_size); void fdt_del_node_and_alias(void *blob, const char *alias); +u64 fdt_translate_address(void *blob, int node_offset, const u32 *in_addr); #endif /* ifdef CONFIG_OF_LIBFDT */ #endif /* ifndef __FDT_SUPPORT_H */ |