#include <linux/kernel.h> #include <linux/export.h> #include <linux/spinlock_types.h> #include <linux/init.h> #include <asm/page.h> #include <asm/setup.h> #include <asm/io.h> #include <asm/cpufeature.h> #include <asm/special_insns.h> #include <asm/pgtable.h> #include <asm/olpc_ofw.h> /* address of OFW callback interface; will be NULL if OFW isn't found */ static int (*olpc_ofw_cif)(int *); /* page dir entry containing OFW's pgdir table; filled in by head_32.S */ u32 olpc_ofw_pgd __initdata; static DEFINE_SPINLOCK(ofw_lock); #define MAXARGS 10 void __init setup_olpc_ofw_pgd(void) { pgd_t *base, *ofw_pde; if (!olpc_ofw_cif) return; /* fetch OFW's PDE */ base = early_ioremap(olpc_ofw_pgd, sizeof(olpc_ofw_pgd) * PTRS_PER_PGD); if (!base) { printk(KERN_ERR "failed to remap OFW's pgd - disabling OFW!\n"); olpc_ofw_cif = NULL; return; } ofw_pde = &base[OLPC_OFW_PDE_NR]; /* install OFW's PDE permanently into the kernel's pgtable */ set_pgd(&swapper_pg_dir[OLPC_OFW_PDE_NR], *ofw_pde); /* implicit optimization barrier here due to uninline function return */ early_iounmap(base, sizeof(olpc_ofw_pgd) * PTRS_PER_PGD); } int __olpc_ofw(const char *name, int nr_args, const void **args, int nr_res, void **res) { int ofw_args[MAXARGS + 3]; unsigned long flags; int ret, i, *p; BUG_ON(nr_args + nr_res > MAXARGS); if (!olpc_ofw_cif) return -EIO; ofw_args[0] = (int)name; ofw_args[1] = nr_args; ofw_args[2] = nr_res; p = &ofw_args[3]; for (i = 0; i < nr_args; i++, p++) *p = (int)args[i]; /* call into ofw */ spin_lock_irqsave(&ofw_lock, flags); ret = olpc_ofw_cif(ofw_args); spin_unlock_irqrestore(&ofw_lock, flags); if (!ret) { for (i = 0; i < nr_res; i++, p++) *((int *)res[i]) = *p; } return ret; } EXPORT_SYMBOL_GPL(__olpc_ofw); bool olpc_ofw_present(void) { return olpc_ofw_cif != NULL; } EXPORT_SYMBOL_GPL(olpc_ofw_present); /* OFW cif _should_ be above this address */ #define OFW_MIN 0xff000000 /* OFW starts on a 1MB boundary */ #define OFW_BOUND (1<<20) void __init olpc_ofw_detect(void) { struct olpc_ofw_header *hdr = &boot_params.olpc_ofw_header; unsigned long start; /* ensure OFW booted us by checking for "OFW " string */ if (hdr->ofw_magic != OLPC_OFW_SIG) return; olpc_ofw_cif = (int (*)(int *))hdr->cif_handler; if ((unsigned long)olpc_ofw_cif < OFW_MIN) { printk(KERN_ERR "OFW detected, but cif has invalid address 0x%lx - disabling.\n", (unsigned long)olpc_ofw_cif); olpc_ofw_cif = NULL; return; } /* determine where OFW starts in memory */ start = round_down((unsigned long)olpc_ofw_cif, OFW_BOUND); printk(KERN_INFO "OFW detected in memory, cif @ 0x%lx (reserving top %ldMB)\n", (unsigned long)olpc_ofw_cif, (-start) >> 20); reserve_top_address(-start); } bool __init olpc_ofw_is_installed(void) { return olpc_ofw_cif != NULL; }