Initial commit: OpenHarmony-v4.0-ReleaseOpenHarmony-v4.0-Release

1 files changed, 933 insertions, 0 deletions

diff --git a/arch/mips/kernel/vpe.c b/arch/mips/kernel/vpe.c
new file mode 100644
index 000000000..d0d832ab3
--- /dev/null
+++ b/arch/mips/kernel/vpe.c
@@ -0,0 +1,933 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2004, 2005 MIPS Technologies, Inc.  All rights reserved.
+ * Copyright (C) 2013 Imagination Technologies Ltd.
+ *
+ * VPE spport module for loading a MIPS SP program into VPE1. The SP
+ * environment is rather simple since there are no TLBs. It needs
+ * to be relocatable (or partiall linked). Initialize your stack in
+ * the startup-code. The loader looks for the symbol __start and sets
+ * up the execution to resume from there. To load and run, simply do
+ * a cat SP 'binary' to the /dev/vpe1 device.
+ */
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+#include <linux/vmalloc.h>
+#include <linux/elf.h>
+#include <linux/seq_file.h>
+#include <linux/syscalls.h>
+#include <linux/moduleloader.h>
+#include <linux/interrupt.h>
+#include <linux/poll.h>
+#include <linux/memblock.h>
+#include <asm/mipsregs.h>
+#include <asm/mipsmtregs.h>
+#include <asm/cacheflush.h>
+#include <linux/atomic.h>
+#include <asm/mips_mt.h>
+#include <asm/processor.h>
+#include <asm/vpe.h>
+
+#ifndef ARCH_SHF_SMALL
+#define ARCH_SHF_SMALL 0
+#endif
+
+/* If this is set, the section belongs in the init part of the module */
+#define INIT_OFFSET_MASK (1UL << (BITS_PER_LONG-1))
+
+struct vpe_control vpecontrol = {
+        .vpe_list_lock  = __SPIN_LOCK_UNLOCKED(vpe_list_lock),
+        .vpe_list       = LIST_HEAD_INIT(vpecontrol.vpe_list),
+        .tc_list_lock   = __SPIN_LOCK_UNLOCKED(tc_list_lock),
+        .tc_list        = LIST_HEAD_INIT(vpecontrol.tc_list)
+};
+
+/* get the vpe associated with this minor */
+struct vpe *get_vpe(int minor)
+{
+        struct vpe *res, *v;
+
+        if (!cpu_has_mipsmt)
+                return NULL;
+
+        res = NULL;
+        spin_lock(&vpecontrol.vpe_list_lock);
+        list_for_each_entry(v, &vpecontrol.vpe_list, list) {
+                if (v->minor == VPE_MODULE_MINOR) {
+                        res = v;
+                        break;
+                }
+        }
+        spin_unlock(&vpecontrol.vpe_list_lock);
+
+        return res;
+}
+
+/* get the vpe associated with this minor */
+struct tc *get_tc(int index)
+{
+        struct tc *res, *t;
+
+        res = NULL;
+        spin_lock(&vpecontrol.tc_list_lock);
+        list_for_each_entry(t, &vpecontrol.tc_list, list) {
+                if (t->index == index) {
+                        res = t;
+                        break;
+                }
+        }
+        spin_unlock(&vpecontrol.tc_list_lock);
+
+        return res;
+}
+
+/* allocate a vpe and associate it with this minor (or index) */
+struct vpe *alloc_vpe(int minor)
+{
+        struct vpe *v;
+
+        v = kzalloc(sizeof(struct vpe), GFP_KERNEL);
+        if (v == NULL)
+                goto out;
+
+        INIT_LIST_HEAD(&v->tc);
+        spin_lock(&vpecontrol.vpe_list_lock);
+        list_add_tail(&v->list, &vpecontrol.vpe_list);
+        spin_unlock(&vpecontrol.vpe_list_lock);
+
+        INIT_LIST_HEAD(&v->notify);
+        v->minor = VPE_MODULE_MINOR;
+
+out:
+        return v;
+}
+
+/* allocate a tc. At startup only tc0 is running, all other can be halted. */
+struct tc *alloc_tc(int index)
+{
+        struct tc *tc;
+
+        tc = kzalloc(sizeof(struct tc), GFP_KERNEL);
+        if (tc == NULL)
+                goto out;
+
+        INIT_LIST_HEAD(&tc->tc);
+        tc->index = index;
+
+        spin_lock(&vpecontrol.tc_list_lock);
+        list_add_tail(&tc->list, &vpecontrol.tc_list);
+        spin_unlock(&vpecontrol.tc_list_lock);
+
+out:
+        return tc;
+}
+
+/* clean up and free everything */
+void release_vpe(struct vpe *v)
+{
+        list_del(&v->list);
+        if (v->load_addr)
+                release_progmem(v->load_addr);
+        kfree(v);
+}
+
+/* Find some VPE program space */
+void *alloc_progmem(unsigned long len)
+{
+        void *addr;
+
+#ifdef CONFIG_MIPS_VPE_LOADER_TOM
+        /*
+         * This means you must tell Linux to use less memory than you
+         * physically have, for example by passing a mem= boot argument.
+         */
+        addr = pfn_to_kaddr(max_low_pfn);
+        memset(addr, 0, len);
+#else
+        /* simple grab some mem for now */
+        addr = kzalloc(len, GFP_KERNEL);
+#endif
+
+        return addr;
+}
+
+void release_progmem(void *ptr)
+{
+#ifndef CONFIG_MIPS_VPE_LOADER_TOM
+        kfree(ptr);
+#endif
+}
+
+/* Update size with this section: return offset. */
+static long get_offset(unsigned long *size, Elf_Shdr *sechdr)
+{
+        long ret;
+
+        ret = ALIGN(*size, sechdr->sh_addralign ? : 1);
+        *size = ret + sechdr->sh_size;
+        return ret;
+}
+
+/* Lay out the SHF_ALLOC sections in a way not dissimilar to how ld
+   might -- code, read-only data, read-write data, small data.  Tally
+   sizes, and place the offsets into sh_entsize fields: high bit means it
+   belongs in init. */
+static void layout_sections(struct module *mod, const Elf_Ehdr *hdr,
+                            Elf_Shdr *sechdrs, const char *secstrings)
+{
+        static unsigned long const masks[][2] = {
+                /* NOTE: all executable code must be the first section
+                 * in this array; otherwise modify the text_size
+                 * finder in the two loops below */
+                {SHF_EXECINSTR | SHF_ALLOC, ARCH_SHF_SMALL},
+                {SHF_ALLOC, SHF_WRITE | ARCH_SHF_SMALL},
+                {SHF_WRITE | SHF_ALLOC, ARCH_SHF_SMALL},
+                {ARCH_SHF_SMALL | SHF_ALLOC, 0}
+        };
+        unsigned int m, i;
+
+        for (i = 0; i < hdr->e_shnum; i++)
+                sechdrs[i].sh_entsize = ~0UL;
+
+        for (m = 0; m < ARRAY_SIZE(masks); ++m) {
+                for (i = 0; i < hdr->e_shnum; ++i) {
+                        Elf_Shdr *s = &sechdrs[i];
+
+                        if ((s->sh_flags & masks[m][0]) != masks[m][0]
+                            || (s->sh_flags & masks[m][1])
+                            || s->sh_entsize != ~0UL)
+                                continue;
+                        s->sh_entsize =
+                                get_offset((unsigned long *)&mod->core_layout.size, s);
+                }
+
+                if (m == 0)
+                        mod->core_layout.text_size = mod->core_layout.size;
+
+        }
+}
+
+/* from module-elf32.c, but subverted a little */
+
+struct mips_hi16 {
+        struct mips_hi16 *next;
+        Elf32_Addr *addr;
+        Elf32_Addr value;
+};
+
+static struct mips_hi16 *mips_hi16_list;
+static unsigned int gp_offs, gp_addr;
+
+static int apply_r_mips_none(struct module *me, uint32_t *location,
+                             Elf32_Addr v)
+{
+        return 0;
+}
+
+static int apply_r_mips_gprel16(struct module *me, uint32_t *location,
+                                Elf32_Addr v)
+{
+        int rel;
+
+        if (!(*location & 0xffff)) {
+                rel = (int)v - gp_addr;
+        } else {
+                /* .sbss + gp(relative) + offset */
+                /* kludge! */
+                rel =  (int)(short)((int)v + gp_offs +
+                                    (int)(short)(*location & 0xffff) - gp_addr);
+        }
+
+        if ((rel > 32768) || (rel < -32768)) {
+                pr_debug("VPE loader: apply_r_mips_gprel16: relative address 0x%x out of range of gp register\n",
+                         rel);
+                return -ENOEXEC;
+        }
+
+        *location = (*location & 0xffff0000) | (rel & 0xffff);
+
+        return 0;
+}
+
+static int apply_r_mips_pc16(struct module *me, uint32_t *location,
+                             Elf32_Addr v)
+{
+        int rel;
+        rel = (((unsigned int)v - (unsigned int)location));
+        rel >>= 2; /* because the offset is in _instructions_ not bytes. */
+        rel -= 1;  /* and one instruction less due to the branch delay slot. */
+
+        if ((rel > 32768) || (rel < -32768)) {
+                pr_debug("VPE loader: apply_r_mips_pc16: relative address out of range 0x%x\n",
+                         rel);
+                return -ENOEXEC;
+        }
+
+        *location = (*location & 0xffff0000) | (rel & 0xffff);
+
+        return 0;
+}
+
+static int apply_r_mips_32(struct module *me, uint32_t *location,
+                           Elf32_Addr v)
+{
+        *location += v;
+
+        return 0;
+}
+
+static int apply_r_mips_26(struct module *me, uint32_t *location,
+                           Elf32_Addr v)
+{
+        if (v % 4) {
+                pr_debug("VPE loader: apply_r_mips_26: unaligned relocation\n");
+                return -ENOEXEC;
+        }
+
+/*
+ * Not desperately convinced this is a good check of an overflow condition
+ * anyway. But it gets in the way of handling undefined weak symbols which
+ * we want to set to zero.
+ * if ((v & 0xf0000000) != (((unsigned long)location + 4) & 0xf0000000)) {
+ * printk(KERN_ERR
+ * "module %s: relocation overflow\n",
+ * me->name);
+ * return -ENOEXEC;
+ * }
+ */
+
+        *location = (*location & ~0x03ffffff) |
+                ((*location + (v >> 2)) & 0x03ffffff);
+        return 0;
+}
+
+static int apply_r_mips_hi16(struct module *me, uint32_t *location,
+                             Elf32_Addr v)
+{
+        struct mips_hi16 *n;
+
+        /*
+         * We cannot relocate this one now because we don't know the value of
+         * the carry we need to add.  Save the information, and let LO16 do the
+         * actual relocation.
+         */
+        n = kmalloc(sizeof(*n), GFP_KERNEL);
+        if (!n)
+                return -ENOMEM;
+
+        n->addr = location;
+        n->value = v;
+        n->next = mips_hi16_list;
+        mips_hi16_list = n;
+
+        return 0;
+}
+
+static int apply_r_mips_lo16(struct module *me, uint32_t *location,
+                             Elf32_Addr v)
+{
+        unsigned long insnlo = *location;
+        Elf32_Addr val, vallo;
+        struct mips_hi16 *l, *next;
+
+        /* Sign extend the addend we extract from the lo insn.  */
+        vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000;
+
+        if (mips_hi16_list != NULL) {
+
+                l = mips_hi16_list;
+                while (l != NULL) {
+                        unsigned long insn;
+
+                        /*
+                         * The value for the HI16 had best be the same.
+                         */
+                        if (v != l->value) {
+                                pr_debug("VPE loader: apply_r_mips_lo16/hi16: inconsistent value information\n");
+                                goto out_free;
+                        }
+
+                        /*
+                         * Do the HI16 relocation.  Note that we actually don't
+                         * need to know anything about the LO16 itself, except
+                         * where to find the low 16 bits of the addend needed
+                         * by the LO16.
+                         */
+                        insn = *l->addr;
+                        val = ((insn & 0xffff) << 16) + vallo;
+                        val += v;
+
+                        /*
+                         * Account for the sign extension that will happen in
+                         * the low bits.
+                         */
+                        val = ((val >> 16) + ((val & 0x8000) != 0)) & 0xffff;
+
+                        insn = (insn & ~0xffff) | val;
+                        *l->addr = insn;
+
+                        next = l->next;
+                        kfree(l);
+                        l = next;
+                }
+
+                mips_hi16_list = NULL;
+        }
+
+        /*
+         * Ok, we're done with the HI16 relocs.  Now deal with the LO16.
+         */
+        val = v + vallo;
+        insnlo = (insnlo & ~0xffff) | (val & 0xffff);
+        *location = insnlo;
+
+        return 0;
+
+out_free:
+        while (l != NULL) {
+                next = l->next;
+                kfree(l);
+                l = next;
+        }
+        mips_hi16_list = NULL;
+
+        return -ENOEXEC;
+}
+
+static int (*reloc_handlers[]) (struct module *me, uint32_t *location,
+                                Elf32_Addr v) = {
+        [R_MIPS_NONE]   = apply_r_mips_none,
+        [R_MIPS_32]     = apply_r_mips_32,
+        [R_MIPS_26]     = apply_r_mips_26,
+        [R_MIPS_HI16]   = apply_r_mips_hi16,
+        [R_MIPS_LO16]   = apply_r_mips_lo16,
+        [R_MIPS_GPREL16] = apply_r_mips_gprel16,
+        [R_MIPS_PC16] = apply_r_mips_pc16
+};
+
+static char *rstrs[] = {
+        [R_MIPS_NONE]   = "MIPS_NONE",
+        [R_MIPS_32]     = "MIPS_32",
+        [R_MIPS_26]     = "MIPS_26",
+        [R_MIPS_HI16]   = "MIPS_HI16",
+        [R_MIPS_LO16]   = "MIPS_LO16",
+        [R_MIPS_GPREL16] = "MIPS_GPREL16",
+        [R_MIPS_PC16] = "MIPS_PC16"
+};
+
+static int apply_relocations(Elf32_Shdr *sechdrs,
+                      const char *strtab,
+                      unsigned int symindex,
+                      unsigned int relsec,
+                      struct module *me)
+{
+        Elf32_Rel *rel = (void *) sechdrs[relsec].sh_addr;
+        Elf32_Sym *sym;
+        uint32_t *location;
+        unsigned int i;
+        Elf32_Addr v;
+        int res;
+
+        for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
+                Elf32_Word r_info = rel[i].r_info;
+
+                /* This is where to make the change */
+                location = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
+                        + rel[i].r_offset;
+                /* This is the symbol it is referring to */
+                sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
+                        + ELF32_R_SYM(r_info);
+
+                if (!sym->st_value) {
+                        pr_debug("%s: undefined weak symbol %s\n",
+                                 me->name, strtab + sym->st_name);
+                        /* just print the warning, dont barf */
+                }
+
+                v = sym->st_value;
+
+                res = reloc_handlers[ELF32_R_TYPE(r_info)](me, location, v);
+                if (res) {
+                        char *r = rstrs[ELF32_R_TYPE(r_info)];
+                        pr_warn("VPE loader: .text+0x%x relocation type %s for symbol \"%s\" failed\n",
+                                rel[i].r_offset, r ? r : "UNKNOWN",
+                                strtab + sym->st_name);
+                        return res;
+                }
+        }
+
+        return 0;
+}
+
+static inline void save_gp_address(unsigned int secbase, unsigned int rel)
+{
+        gp_addr = secbase + rel;
+        gp_offs = gp_addr - (secbase & 0xffff0000);
+}
+/* end module-elf32.c */
+
+/* Change all symbols so that sh_value encodes the pointer directly. */
+static void simplify_symbols(Elf_Shdr *sechdrs,
+                            unsigned int symindex,
+                            const char *strtab,
+                            const char *secstrings,
+                            unsigned int nsecs, struct module *mod)
+{
+        Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
+        unsigned long secbase, bssbase = 0;
+        unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
+        int size;
+
+        /* find the .bss section for COMMON symbols */
+        for (i = 0; i < nsecs; i++) {
+                if (strncmp(secstrings + sechdrs[i].sh_name, ".bss", 4) == 0) {
+                        bssbase = sechdrs[i].sh_addr;
+                        break;
+                }
+        }
+
+        for (i = 1; i < n; i++) {
+                switch (sym[i].st_shndx) {
+                case SHN_COMMON:
+                        /* Allocate space for the symbol in the .bss section.
+                           st_value is currently size.
+                           We want it to have the address of the symbol. */
+
+                        size = sym[i].st_value;
+                        sym[i].st_value = bssbase;
+
+                        bssbase += size;
+                        break;
+
+                case SHN_ABS:
+                        /* Don't need to do anything */
+                        break;
+
+                case SHN_UNDEF:
+                        /* ret = -ENOENT; */
+                        break;
+
+                case SHN_MIPS_SCOMMON:
+                        pr_debug("simplify_symbols: ignoring SHN_MIPS_SCOMMON symbol <%s> st_shndx %d\n",
+                                 strtab + sym[i].st_name, sym[i].st_shndx);
+                        /* .sbss section */
+                        break;
+
+                default:
+                        secbase = sechdrs[sym[i].st_shndx].sh_addr;
+
+                        if (strncmp(strtab + sym[i].st_name, "_gp", 3) == 0)
+                                save_gp_address(secbase, sym[i].st_value);
+
+                        sym[i].st_value += secbase;
+                        break;
+                }
+        }
+}
+
+#ifdef DEBUG_ELFLOADER
+static void dump_elfsymbols(Elf_Shdr *sechdrs, unsigned int symindex,
+                            const char *strtab, struct module *mod)
+{
+        Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
+        unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
+
+        pr_debug("dump_elfsymbols: n %d\n", n);
+        for (i = 1; i < n; i++) {
+                pr_debug(" i %d name <%s> 0x%x\n", i, strtab + sym[i].st_name,
+                         sym[i].st_value);
+        }
+}
+#endif
+
+static int find_vpe_symbols(struct vpe *v, Elf_Shdr *sechdrs,
+                                      unsigned int symindex, const char *strtab,
+                                      struct module *mod)
+{
+        Elf_Sym *sym = (void *)sechdrs[symindex].sh_addr;
+        unsigned int i, n = sechdrs[symindex].sh_size / sizeof(Elf_Sym);
+
+        for (i = 1; i < n; i++) {
+                if (strcmp(strtab + sym[i].st_name, "__start") == 0)
+                        v->__start = sym[i].st_value;
+
+                if (strcmp(strtab + sym[i].st_name, "vpe_shared") == 0)
+                        v->shared_ptr = (void *)sym[i].st_value;
+        }
+
+        if ((v->__start == 0) || (v->shared_ptr == NULL))
+                return -1;
+
+        return 0;
+}
+
+/*
+ * Allocates a VPE with some program code space(the load address), copies the
+ * contents of the program (p)buffer performing relocatations/etc, free's it
+ * when finished.
+ */
+static int vpe_elfload(struct vpe *v)
+{
+        Elf_Ehdr *hdr;
+        Elf_Shdr *sechdrs;
+        long err = 0;
+        char *secstrings, *strtab = NULL;
+        unsigned int len, i, symindex = 0, strindex = 0, relocate = 0;
+        struct module mod; /* so we can re-use the relocations code */
+
+        memset(&mod, 0, sizeof(struct module));
+        strcpy(mod.name, "VPE loader");
+
+        hdr = (Elf_Ehdr *) v->pbuffer;
+        len = v->plen;
+
+        /* Sanity checks against insmoding binaries or wrong arch,
+           weird elf version */
+        if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) != 0
+            || (hdr->e_type != ET_REL && hdr->e_type != ET_EXEC)
+            || !elf_check_arch(hdr)
+            || hdr->e_shentsize != sizeof(*sechdrs)) {
+                pr_warn("VPE loader: program wrong arch or weird elf version\n");
+
+                return -ENOEXEC;
+        }
+
+        if (hdr->e_type == ET_REL)
+                relocate = 1;
+
+        if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) {
+                pr_err("VPE loader: program length %u truncated\n", len);
+
+                return -ENOEXEC;
+        }
+
+        /* Convenience variables */
+        sechdrs = (void *)hdr + hdr->e_shoff;
+        secstrings = (void *)hdr + sechdrs[hdr->e_shstrndx].sh_offset;
+        sechdrs[0].sh_addr = 0;
+
+        /* And these should exist, but gcc whinges if we don't init them */
+        symindex = strindex = 0;
+
+        if (relocate) {
+                for (i = 1; i < hdr->e_shnum; i++) {
+                        if ((sechdrs[i].sh_type != SHT_NOBITS) &&
+                            (len < sechdrs[i].sh_offset + sechdrs[i].sh_size)) {
+                                pr_err("VPE program length %u truncated\n",
+                                       len);
+                                return -ENOEXEC;
+                        }
+
+                        /* Mark all sections sh_addr with their address in the
+                           temporary image. */
+                        sechdrs[i].sh_addr = (size_t) hdr +
+                                sechdrs[i].sh_offset;
+
+                        /* Internal symbols and strings. */
+                        if (sechdrs[i].sh_type == SHT_SYMTAB) {
+                                symindex = i;
+                                strindex = sechdrs[i].sh_link;
+                                strtab = (char *)hdr +
+                                        sechdrs[strindex].sh_offset;
+                        }
+                }
+                layout_sections(&mod, hdr, sechdrs, secstrings);
+        }
+
+        v->load_addr = alloc_progmem(mod.core_layout.size);
+        if (!v->load_addr)
+                return -ENOMEM;
+
+        pr_info("VPE loader: loading to %p\n", v->load_addr);
+
+        if (relocate) {
+                for (i = 0; i < hdr->e_shnum; i++) {
+                        void *dest;
+
+                        if (!(sechdrs[i].sh_flags & SHF_ALLOC))
+                                continue;
+
+                        dest = v->load_addr + sechdrs[i].sh_entsize;
+
+                        if (sechdrs[i].sh_type != SHT_NOBITS)
+                                memcpy(dest, (void *)sechdrs[i].sh_addr,
+                                       sechdrs[i].sh_size);
+                        /* Update sh_addr to point to copy in image. */
+                        sechdrs[i].sh_addr = (unsigned long)dest;
+
+                        pr_debug(" section sh_name %s sh_addr 0x%x\n",
+                                 secstrings + sechdrs[i].sh_name,
+                                 sechdrs[i].sh_addr);
+                }
+
+                /* Fix up syms, so that st_value is a pointer to location. */
+                simplify_symbols(sechdrs, symindex, strtab, secstrings,
+                                 hdr->e_shnum, &mod);
+
+                /* Now do relocations. */
+                for (i = 1; i < hdr->e_shnum; i++) {
+                        const char *strtab = (char *)sechdrs[strindex].sh_addr;
+                        unsigned int info = sechdrs[i].sh_info;
+
+                        /* Not a valid relocation section? */
+                        if (info >= hdr->e_shnum)
+                                continue;
+
+                        /* Don't bother with non-allocated sections */
+                        if (!(sechdrs[info].sh_flags & SHF_ALLOC))
+                                continue;
+
+                        if (sechdrs[i].sh_type == SHT_REL)
+                                err = apply_relocations(sechdrs, strtab,
+                                                        symindex, i, &mod);
+                        else if (sechdrs[i].sh_type == SHT_RELA)
+                                err = apply_relocate_add(sechdrs, strtab,
+                                                         symindex, i, &mod);
+                        if (err < 0)
+                                return err;
+
+                }
+        } else {
+                struct elf_phdr *phdr = (struct elf_phdr *)
+                                                ((char *)hdr + hdr->e_phoff);
+
+                for (i = 0; i < hdr->e_phnum; i++) {
+                        if (phdr->p_type == PT_LOAD) {
+                                memcpy((void *)phdr->p_paddr,
+                                       (char *)hdr + phdr->p_offset,
+                                       phdr->p_filesz);
+                                memset((void *)phdr->p_paddr + phdr->p_filesz,
+                                       0, phdr->p_memsz - phdr->p_filesz);
+                    }
+                    phdr++;
+                }
+
+                for (i = 0; i < hdr->e_shnum; i++) {
+                        /* Internal symbols and strings. */
+                        if (sechdrs[i].sh_type == SHT_SYMTAB) {
+                                symindex = i;
+                                strindex = sechdrs[i].sh_link;
+                                strtab = (char *)hdr +
+                                        sechdrs[strindex].sh_offset;
+
+                                /*
+                                 * mark symtab's address for when we try
+                                 * to find the magic symbols
+                                 */
+                                sechdrs[i].sh_addr = (size_t) hdr +
+                                        sechdrs[i].sh_offset;
+                        }
+                }
+        }
+
+        /* make sure it's physically written out */
+        flush_icache_range((unsigned long)v->load_addr,
+                           (unsigned long)v->load_addr + v->len);
+
+        if ((find_vpe_symbols(v, sechdrs, symindex, strtab, &mod)) < 0) {
+                if (v->__start == 0) {
+                        pr_warn("VPE loader: program does not contain a __start symbol\n");
+                        return -ENOEXEC;
+                }
+
+                if (v->shared_ptr == NULL)
+                        pr_warn("VPE loader: program does not contain vpe_shared symbol.\n"
+                                " Unable to use AMVP (AP/SP) facilities.\n");
+        }
+
+        pr_info(" elf loaded\n");
+        return 0;
+}
+
+static int getcwd(char *buff, int size)
+{
+        mm_segment_t old_fs;
+        int ret;
+
+        old_fs = get_fs();
+        set_fs(KERNEL_DS);
+
+        ret = sys_getcwd(buff, size);
+
+        set_fs(old_fs);
+
+        return ret;
+}
+
+/* checks VPE is unused and gets ready to load program  */
+static int vpe_open(struct inode *inode, struct file *filp)
+{
+        enum vpe_state state;
+        struct vpe_notifications *notifier;
+        struct vpe *v;
+        int ret;
+
+        if (VPE_MODULE_MINOR != iminor(inode)) {
+                /* assume only 1 device at the moment. */
+                pr_warn("VPE loader: only vpe1 is supported\n");
+
+                return -ENODEV;
+        }
+
+        v = get_vpe(aprp_cpu_index());
+        if (v == NULL) {
+                pr_warn("VPE loader: unable to get vpe\n");
+
+                return -ENODEV;
+        }
+
+        state = xchg(&v->state, VPE_STATE_INUSE);
+        if (state != VPE_STATE_UNUSED) {
+                pr_debug("VPE loader: tc in use dumping regs\n");
+
+                list_for_each_entry(notifier, &v->notify, list)
+                        notifier->stop(aprp_cpu_index());
+
+                release_progmem(v->load_addr);
+                cleanup_tc(get_tc(aprp_cpu_index()));
+        }
+
+        /* this of-course trashes what was there before... */
+        v->pbuffer = vmalloc(P_SIZE);
+        if (!v->pbuffer) {
+                pr_warn("VPE loader: unable to allocate memory\n");
+                return -ENOMEM;
+        }
+        v->plen = P_SIZE;
+        v->load_addr = NULL;
+        v->len = 0;
+
+        v->cwd[0] = 0;
+        ret = getcwd(v->cwd, VPE_PATH_MAX);
+        if (ret < 0)
+                pr_warn("VPE loader: open, getcwd returned %d\n", ret);
+
+        v->shared_ptr = NULL;
+        v->__start = 0;
+
+        return 0;
+}
+
+static int vpe_release(struct inode *inode, struct file *filp)
+{
+#if defined(CONFIG_MIPS_VPE_LOADER_MT) || defined(CONFIG_MIPS_VPE_LOADER_CMP)
+        struct vpe *v;
+        Elf_Ehdr *hdr;
+        int ret = 0;
+
+        v = get_vpe(aprp_cpu_index());
+        if (v == NULL)
+                return -ENODEV;
+
+        hdr = (Elf_Ehdr *) v->pbuffer;
+        if (memcmp(hdr->e_ident, ELFMAG, SELFMAG) == 0) {
+                if (vpe_elfload(v) >= 0) {
+                        vpe_run(v);
+                } else {
+                        pr_warn("VPE loader: ELF load failed.\n");
+                        ret = -ENOEXEC;
+                }
+        } else {
+                pr_warn("VPE loader: only elf files are supported\n");
+                ret = -ENOEXEC;
+        }
+
+        /* It's good to be able to run the SP and if it chokes have a look at
+           the /dev/rt?. But if we reset the pointer to the shared struct we
+           lose what has happened. So perhaps if garbage is sent to the vpe
+           device, use it as a trigger for the reset. Hopefully a nice
+           executable will be along shortly. */
+        if (ret < 0)
+                v->shared_ptr = NULL;
+
+        vfree(v->pbuffer);
+        v->plen = 0;
+
+        return ret;
+#else
+        pr_warn("VPE loader: ELF load failed.\n");
+        return -ENOEXEC;
+#endif
+}
+
+static ssize_t vpe_write(struct file *file, const char __user *buffer,
+                         size_t count, loff_t *ppos)
+{
+        size_t ret = count;
+        struct vpe *v;
+
+        if (iminor(file_inode(file)) != VPE_MODULE_MINOR)
+                return -ENODEV;
+
+        v = get_vpe(aprp_cpu_index());
+
+        if (v == NULL)
+                return -ENODEV;
+
+        if ((count + v->len) > v->plen) {
+                pr_warn("VPE loader: elf size too big. Perhaps strip unneeded symbols\n");
+                return -ENOMEM;
+        }
+
+        count -= copy_from_user(v->pbuffer + v->len, buffer, count);
+        if (!count)
+                return -EFAULT;
+
+        v->len += count;
+        return ret;
+}
+
+const struct file_operations vpe_fops = {
+        .owner = THIS_MODULE,
+        .open = vpe_open,
+        .release = vpe_release,
+        .write = vpe_write,
+        .llseek = noop_llseek,
+};
+
+void *vpe_get_shared(int index)
+{
+        struct vpe *v = get_vpe(index);
+
+        if (v == NULL)
+                return NULL;
+
+        return v->shared_ptr;
+}
+EXPORT_SYMBOL(vpe_get_shared);
+
+int vpe_notify(int index, struct vpe_notifications *notify)
+{
+        struct vpe *v = get_vpe(index);
+
+        if (v == NULL)
+                return -1;
+
+        list_add(&notify->list, &v->notify);
+        return 0;
+}
+EXPORT_SYMBOL(vpe_notify);
+
+char *vpe_getcwd(int index)
+{
+        struct vpe *v = get_vpe(index);
+
+        if (v == NULL)
+                return NULL;
+
+        return v->cwd;
+}
+EXPORT_SYMBOL(vpe_getcwd);
+
+module_init(vpe_module_init);
+module_exit(vpe_module_exit);
+MODULE_DESCRIPTION("MIPS VPE Loader");
+MODULE_AUTHOR("Elizabeth Oldham, MIPS Technologies, Inc.");
+MODULE_LICENSE("GPL");