More AP / SP bits for the 34K, the Malta bits and things. Still wants
a little polishing.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/kernel/vpe.c b/arch/mips/kernel/vpe.c
new file mode 100644
index 0000000..6bf42ba
--- /dev/null
+++ b/arch/mips/kernel/vpe.c
@@ -0,0 +1,1295 @@
+/*
+ * Copyright (C) 2004, 2005 MIPS Technologies, Inc. All rights reserved.
+ *
+ * This program is free software; you can distribute it and/or modify it
+ * under the terms of the GNU General Public License (Version 2) as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
+ *
+ */
+
+/*
+ * VPE support module
+ *
+ * Provides support for loading a MIPS SP program on VPE1.
+ * The SP enviroment is rather simple, no tlb's. It needs to be relocatable
+ * (or partially linked). You should initialise your stack in the startup
+ * code. This loader looks for the symbol __start and sets up
+ * execution to resume from there. The MIPS SDE kit contains suitable examples.
+ *
+ * To load and run, simply cat a SP 'program file' to /dev/vpe1.
+ * i.e cat spapp >/dev/vpe1.
+ *
+ * You'll need to have the following device files.
+ * mknod /dev/vpe0 c 63 0
+ * mknod /dev/vpe1 c 63 1
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <asm/uaccess.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/bootmem.h>
+#include <asm/mipsregs.h>
+#include <asm/cacheflush.h>
+#include <asm/atomic.h>
+#include <asm/cpu.h>
+#include <asm/processor.h>
+#include <asm/system.h>
+
+typedef void *vpe_handle;
+
+// defined here because the kernel module loader doesn't have
+// anything to do with it.
+#define SHN_MIPS_SCOMMON 0xff03
+
+#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))
+
+// temp number,
+#define VPE_MAJOR 63
+
+static char module_name[] = "vpe";
+static int major = 0;
+
+/* grab the likely amount of memory we will need. */
+#ifdef CONFIG_MIPS_VPE_LOADER_TOM
+#define P_SIZE (2 * 1024 * 1024)
+#else
+/* add an overhead to the max kmalloc size for non-striped symbols/etc */
+#define P_SIZE (256 * 1024)
+#endif
+
+#define MAX_VPES 16
+
+enum vpe_state {
+ VPE_STATE_UNUSED = 0,
+ VPE_STATE_INUSE,
+ VPE_STATE_RUNNING
+};
+
+enum tc_state {
+ TC_STATE_UNUSED = 0,
+ TC_STATE_INUSE,
+ TC_STATE_RUNNING,
+ TC_STATE_DYNAMIC
+};
+
+struct vpe;
+typedef struct tc {
+ enum tc_state state;
+ int index;
+
+ /* parent VPE */
+ struct vpe *pvpe;
+
+ /* The list of TC's with this VPE */
+ struct list_head tc;
+
+ /* The global list of tc's */
+ struct list_head list;
+} tc_t;
+
+typedef struct vpe {
+ enum vpe_state state;
+
+ /* (device) minor associated with this vpe */
+ int minor;
+
+ /* elfloader stuff */
+ void *load_addr;
+ u32 len;
+ char *pbuffer;
+ u32 plen;
+
+ unsigned long __start;
+
+ /* tc's associated with this vpe */
+ struct list_head tc;
+
+ /* The list of vpe's */
+ struct list_head list;
+
+ /* shared symbol address */
+ void *shared_ptr;
+} vpe_t;
+
+struct vpecontrol_ {
+ /* Virtual processing elements */
+ struct list_head vpe_list;
+
+ /* Thread contexts */
+ struct list_head tc_list;
+} vpecontrol;
+
+static void release_progmem(void *ptr);
+static void dump_vpe(vpe_t * v);
+extern void save_gp_address(unsigned int secbase, unsigned int rel);
+
+/* get the vpe associated with this minor */
+struct vpe *get_vpe(int minor)
+{
+ struct vpe *v;
+
+ list_for_each_entry(v, &vpecontrol.vpe_list, list) {
+ if (v->minor == minor)
+ return v;
+ }
+
+ printk(KERN_DEBUG "VPE: get_vpe minor %d not found\n", minor);
+ return NULL;
+}
+
+/* get the vpe associated with this minor */
+struct tc *get_tc(int index)
+{
+ struct tc *t;
+
+ list_for_each_entry(t, &vpecontrol.tc_list, list) {
+ if (t->index == index)
+ return t;
+ }
+
+ printk(KERN_DEBUG "VPE: get_tc index %d not found\n", index);
+
+ return NULL;
+}
+
+struct tc *get_tc_unused(void)
+{
+ struct tc *t;
+
+ list_for_each_entry(t, &vpecontrol.tc_list, list) {
+ if (t->state == TC_STATE_UNUSED)
+ return t;
+ }
+
+ printk(KERN_DEBUG "VPE: All TC's are in use\n");
+
+ return NULL;
+}
+
+/* allocate a vpe and associate it with this minor (or index) */
+struct vpe *alloc_vpe(int minor)
+{
+ struct vpe *v;
+
+ if ((v = kmalloc(sizeof(struct vpe), GFP_KERNEL)) == NULL) {
+ printk(KERN_WARNING "VPE: alloc_vpe no mem\n");
+ return NULL;
+ }
+
+ memset(v, 0, sizeof(struct vpe));
+
+ INIT_LIST_HEAD(&v->tc);
+ list_add_tail(&v->list, &vpecontrol.vpe_list);
+
+ v->minor = minor;
+ return v;
+}
+
+/* allocate a tc. At startup only tc0 is running, all other can be halted. */
+struct tc *alloc_tc(int index)
+{
+ struct tc *t;
+
+ if ((t = kmalloc(sizeof(struct tc), GFP_KERNEL)) == NULL) {
+ printk(KERN_WARNING "VPE: alloc_tc no mem\n");
+ return NULL;
+ }
+
+ memset(t, 0, sizeof(struct tc));
+
+ INIT_LIST_HEAD(&t->tc);
+ list_add_tail(&t->list, &vpecontrol.tc_list);
+
+ t->index = index;
+
+ return t;
+}
+
+/* clean up and free everything */
+void release_vpe(struct vpe *v)
+{
+ list_del(&v->list);
+ if (v->load_addr)
+ release_progmem(v);
+ kfree(v);
+}
+
+void dump_mtregs(void)
+{
+ unsigned long val;
+
+ val = read_c0_config3();
+ printk("config3 0x%lx MT %ld\n", val,
+ (val & CONFIG3_MT) >> CONFIG3_MT_SHIFT);
+
+ val = read_c0_mvpconf0();
+ printk("mvpconf0 0x%lx, PVPE %ld PTC %ld M %ld\n", val,
+ (val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT,
+ val & MVPCONF0_PTC, (val & MVPCONF0_M) >> MVPCONF0_M_SHIFT);
+
+ val = read_c0_mvpcontrol();
+ printk("MVPControl 0x%lx, STLB %ld VPC %ld EVP %ld\n", val,
+ (val & MVPCONTROL_STLB) >> MVPCONTROL_STLB_SHIFT,
+ (val & MVPCONTROL_VPC) >> MVPCONTROL_VPC_SHIFT,
+ (val & MVPCONTROL_EVP));
+
+ val = read_c0_vpeconf0();
+ printk("VPEConf0 0x%lx MVP %ld\n", val,
+ (val & VPECONF0_MVP) >> VPECONF0_MVP_SHIFT);
+}
+
+/* Find some VPE program space */
+static void *alloc_progmem(u32 len)
+{
+#ifdef CONFIG_MIPS_VPE_LOADER_TOM
+ /* this means you must tell linux to use less memory than you physically have */
+ return (void *)((max_pfn * PAGE_SIZE) + KSEG0);
+#else
+ // simple grab some mem for now
+ return kmalloc(len, GFP_KERNEL);
+#endif
+}
+
+static 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];
+
+ // || strncmp(secstrings + s->sh_name, ".init", 5) == 0)
+ 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(&mod->core_size, s);
+ }
+
+ if (m == 0)
+ mod->core_text_size = mod->core_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) ) {
+ printk(KERN_ERR
+ "apply_r_mips_gprel16: relative address out of range 0x%x %d\n",
+ rel, 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) ) {
+ printk(KERN_ERR
+ "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) {
+ printk(KERN_ERR "module %s: dangerous relocation mod4\n", me->name);
+ 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;
+
+ /* Sign extend the addend we extract from the lo insn. */
+ vallo = ((insnlo & 0xffff) ^ 0x8000) - 0x8000;
+
+ if (mips_hi16_list != NULL) {
+ struct mips_hi16 *l;
+
+ l = mips_hi16_list;
+ while (l != NULL) {
+ struct mips_hi16 *next;
+ unsigned long insn;
+
+ /*
+ * The value for the HI16 had best be the same.
+ */
+ if (v != l->value) {
+ printk("%d != %d\n", v, l->value);
+ goto out_danger;
+ }
+
+
+ /*
+ * 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_danger:
+ printk(KERN_ERR "module %s: dangerous " "relocation\n", me->name);
+
+ 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
+};
+
+
+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) {
+ printk(KERN_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 ) {
+ printk(KERN_DEBUG
+ "relocation error 0x%x sym refer <%s> value 0x%x "
+ "type 0x%x r_info 0x%x\n",
+ (unsigned int)location, strtab + sym->st_name, v,
+ r_info, ELF32_R_TYPE(r_info));
+ }
+
+ if (res)
+ return res;
+ }
+
+ return 0;
+}
+
+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 int 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 ret = 0, 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;
+ }
+
+ 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:
+
+ printk(KERN_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;
+ }
+
+ }
+
+ return ret;
+}
+
+#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);
+
+ printk(KERN_DEBUG "dump_elfsymbols: n %d\n", n);
+ for (i = 1; i < n; i++) {
+ printk(KERN_DEBUG " i %d name <%s> 0x%x\n", i,
+ strtab + sym[i].st_name, sym[i].st_value);
+ }
+}
+#endif
+
+static void dump_tc(struct tc *t)
+{
+ printk(KERN_WARNING "VPE: TC index %d TCStatus 0x%lx halt 0x%lx\n",
+ t->index, read_tc_c0_tcstatus(), read_tc_c0_tchalt());
+ printk(KERN_WARNING "VPE: tcrestart 0x%lx\n", read_tc_c0_tcrestart());
+}
+
+static void dump_tclist(void)
+{
+ struct tc *t;
+
+ list_for_each_entry(t, &vpecontrol.tc_list, list) {
+ dump_tc(t);
+ }
+}
+
+/* We are prepared so configure and start the VPE... */
+int vpe_run(vpe_t * v)
+{
+ unsigned long val;
+ struct tc *t;
+
+ /* check we are the Master VPE */
+ val = read_c0_vpeconf0();
+ if (!(val & VPECONF0_MVP)) {
+ printk(KERN_WARNING
+ "VPE: only Master VPE's are allowed to configure MT\n");
+ return -1;
+ }
+
+ /* disable MT (using dvpe) */
+ dvpe();
+
+ /* Put MVPE's into 'configuration state' */
+ write_c0_mvpcontrol(read_c0_mvpcontrol() | MVPCONTROL_VPC);
+
+ if (!list_empty(&v->tc)) {
+ if ((t = list_entry(v->tc.next, struct tc, tc)) == NULL) {
+ printk(KERN_WARNING "VPE: TC %d is already in use.\n",
+ t->index);
+ return -ENOEXEC;
+ }
+ } else {
+ printk(KERN_WARNING "VPE: No TC's associated with VPE %d\n",
+ v->minor);
+ return -ENOEXEC;
+ }
+
+ settc(t->index);
+
+ val = read_vpe_c0_vpeconf0();
+
+ /* should check it is halted, and not activated */
+ if ((read_tc_c0_tcstatus() & TCSTATUS_A) || !(read_tc_c0_tchalt() & TCHALT_H)) {
+ printk(KERN_WARNING "VPE: TC %d is already doing something!\n",
+ t->index);
+
+ dump_tclist();
+ return -ENOEXEC;
+ }
+
+ /* Write the address we want it to start running from in the TCPC register. */
+ write_tc_c0_tcrestart((unsigned long)v->__start);
+
+ /* write the sivc_info address to tccontext */
+ write_tc_c0_tccontext((unsigned long)0);
+
+ /* Set up the XTC bit in vpeconf0 to point at our tc */
+ write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() | (t->index << VPECONF0_XTC_SHIFT));
+
+ /* mark the TC as activated, not interrupt exempt and not dynamically allocatable */
+ val = read_tc_c0_tcstatus();
+ val = (val & ~(TCSTATUS_DA | TCSTATUS_IXMT)) | TCSTATUS_A;
+ write_tc_c0_tcstatus(val);
+
+ write_tc_c0_tchalt(read_tc_c0_tchalt() & ~TCHALT_H);
+
+ /* set up VPE1 */
+ write_vpe_c0_vpecontrol(read_vpe_c0_vpecontrol() & ~VPECONTROL_TE); // no multiple TC's
+ write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() | VPECONF0_VPA); // enable this VPE
+
+ /*
+ * The sde-kit passes 'memsize' to __start in $a3, so set something
+ * here...
+ * Or set $a3 (register 7) to zero and define DFLT_STACK_SIZE and
+ * DFLT_HEAP_SIZE when you compile your program
+ */
+
+ mttgpr(7, 0);
+
+ /* set config to be the same as vpe0, particularly kseg0 coherency alg */
+ write_vpe_c0_config(read_c0_config());
+
+ /* clear out any left overs from a previous program */
+ write_vpe_c0_cause(0);
+
+ /* take system out of configuration state */
+ write_c0_mvpcontrol(read_c0_mvpcontrol() & ~MVPCONTROL_VPC);
+
+ /* clear interrupts enabled IE, ERL, EXL, and KSU from c0 status */
+ write_vpe_c0_status(read_vpe_c0_status() & ~(ST0_ERL | ST0_KSU | ST0_IE | ST0_EXL));
+
+ /* set it running */
+ evpe(EVPE_ENABLE);
+
+ return 0;
+}
+
+static unsigned long find_vpe_symbols(vpe_t * 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;
+ }
+ }
+
+ 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.
+*/
+int vpe_elfload(vpe_t * v)
+{
+ Elf_Ehdr *hdr;
+ Elf_Shdr *sechdrs;
+ long err = 0;
+ char *secstrings, *strtab = NULL;
+ unsigned int len, i, symindex = 0, strindex = 0;
+
+ struct module mod; // so we can re-use the relocations code
+
+ memset(&mod, 0, sizeof(struct module));
+ strcpy(mod.name, "VPE dummy prog module");
+
+ 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, 4) != 0
+ || hdr->e_type != ET_REL || !elf_check_arch(hdr)
+ || hdr->e_shentsize != sizeof(*sechdrs)) {
+ printk(KERN_WARNING
+ "VPE program, wrong arch or weird elf version\n");
+
+ return -ENOEXEC;
+ }
+
+ if (len < hdr->e_shoff + hdr->e_shnum * sizeof(Elf_Shdr)) {
+ printk(KERN_ERR "VPE 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;
+
+ for (i = 1; i < hdr->e_shnum; i++) {
+
+ if (sechdrs[i].sh_type != SHT_NOBITS
+ && len < sechdrs[i].sh_offset + sechdrs[i].sh_size) {
+ printk(KERN_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_size);
+ memset(v->load_addr, 0, mod.core_size);
+
+ printk("VPE elf_loader: loading to %p\n", v->load_addr);
+
+ 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;
+ }
+
+ /* Fix up syms, so that st_value is a pointer to location. */
+ err =
+ simplify_symbols(sechdrs, symindex, strtab, secstrings,
+ hdr->e_shnum, &mod);
+ if (err < 0) {
+ printk(KERN_WARNING "VPE: unable to simplify symbols\n");
+ goto cleanup;
+ }
+
+ /* 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) {
+ printk(KERN_WARNING
+ "vpe_elfload: error in relocations err %ld\n",
+ err);
+ goto cleanup;
+ }
+ }
+
+ /* 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) {
+
+ printk(KERN_WARNING
+ "VPE: program doesn't contain __start or vpe_shared symbols\n");
+ err = -ENOEXEC;
+ }
+
+ printk(" elf loaded\n");
+
+cleanup:
+ return err;
+}
+
+static void dump_vpe(vpe_t * v)
+{
+ struct tc *t;
+
+ printk(KERN_DEBUG "VPEControl 0x%lx\n", read_vpe_c0_vpecontrol());
+ printk(KERN_DEBUG "VPEConf0 0x%lx\n", read_vpe_c0_vpeconf0());
+
+ list_for_each_entry(t, &vpecontrol.tc_list, list) {
+ dump_tc(t);
+ }
+}
+
+/* checks for VPE is unused and gets ready to load program */
+static int vpe_open(struct inode *inode, struct file *filp)
+{
+ int minor;
+ vpe_t *v;
+
+ /* assume only 1 device at the mo. */
+ if ((minor = MINOR(inode->i_rdev)) != 1) {
+ printk(KERN_WARNING "VPE: only vpe1 is supported\n");
+ return -ENODEV;
+ }
+
+ if ((v = get_vpe(minor)) == NULL) {
+ printk(KERN_WARNING "VPE: unable to get vpe\n");
+ return -ENODEV;
+ }
+
+ if (v->state != VPE_STATE_UNUSED) {
+ unsigned long tmp;
+ struct tc *t;
+
+ printk(KERN_WARNING "VPE: device %d already in use\n", minor);
+
+ dvpe();
+ dump_vpe(v);
+
+ printk(KERN_WARNING "VPE: re-initialising %d\n", minor);
+
+ release_progmem(v->load_addr);
+
+ t = get_tc(minor);
+ settc(minor);
+ tmp = read_tc_c0_tcstatus();
+
+ /* mark not allocated and not dynamically allocatable */
+ tmp &= ~(TCSTATUS_A | TCSTATUS_DA);
+ tmp |= TCSTATUS_IXMT; /* interrupt exempt */
+ write_tc_c0_tcstatus(tmp);
+
+ write_tc_c0_tchalt(TCHALT_H);
+
+ }
+
+ // allocate it so when we get write ops we know it's expected.
+ v->state = VPE_STATE_INUSE;
+
+ /* this of-course trashes what was there before... */
+ v->pbuffer = vmalloc(P_SIZE);
+ v->plen = P_SIZE;
+ v->load_addr = NULL;
+ v->len = 0;
+
+ return 0;
+}
+
+static int vpe_release(struct inode *inode, struct file *filp)
+{
+ int minor, ret = 0;
+ vpe_t *v;
+ Elf_Ehdr *hdr;
+
+ minor = MINOR(inode->i_rdev);
+ if ((v = get_vpe(minor)) == NULL)
+ return -ENODEV;
+
+ // simple case of fire and forget, so tell the VPE to run...
+
+ hdr = (Elf_Ehdr *) v->pbuffer;
+ if (memcmp(hdr->e_ident, ELFMAG, 4) == 0) {
+ if (vpe_elfload(v) >= 0)
+ vpe_run(v);
+ else {
+ printk(KERN_WARNING "VPE: ELF load failed.\n");
+ ret = -ENOEXEC;
+ }
+ } else {
+ printk(KERN_WARNING "VPE: only elf files are supported\n");
+ ret = -ENOEXEC;
+ }
+
+ // cleanup any temp buffers
+ if (v->pbuffer)
+ vfree(v->pbuffer);
+ v->plen = 0;
+ return ret;
+}
+
+static ssize_t vpe_write(struct file *file, const char __user * buffer,
+ size_t count, loff_t * ppos)
+{
+ int minor;
+ size_t ret = count;
+ vpe_t *v;
+
+ minor = MINOR(file->f_dentry->d_inode->i_rdev);
+ if ((v = get_vpe(minor)) == NULL)
+ return -ENODEV;
+
+ if (v->pbuffer == NULL) {
+ printk(KERN_ERR "vpe_write: no pbuffer\n");
+ return -ENOMEM;
+ }
+
+ if ((count + v->len) > v->plen) {
+ printk(KERN_WARNING
+ "VPE Loader: elf size too big. Perhaps strip uneeded symbols\n");
+ return -ENOMEM;
+ }
+
+ count -= copy_from_user(v->pbuffer + v->len, buffer, count);
+ if (!count) {
+ printk("vpe_write: copy_to_user failed\n");
+ return -EFAULT;
+ }
+
+ v->len += count;
+ return ret;
+}
+
+static struct file_operations vpe_fops = {
+ .owner = THIS_MODULE,
+ .open = vpe_open,
+ .release = vpe_release,
+ .write = vpe_write
+};
+
+/* module wrapper entry points */
+/* give me a vpe */
+vpe_handle vpe_alloc(void)
+{
+ int i;
+ struct vpe *v;
+
+ /* find a vpe */
+ for (i = 1; i < MAX_VPES; i++) {
+ if ((v = get_vpe(i)) != NULL) {
+ v->state = VPE_STATE_INUSE;
+ return v;
+ }
+ }
+ return NULL;
+}
+
+EXPORT_SYMBOL(vpe_alloc);
+
+/* start running from here */
+int vpe_start(vpe_handle vpe, unsigned long start)
+{
+ struct vpe *v = vpe;
+
+ v->__start = start;
+ return vpe_run(v);
+}
+
+EXPORT_SYMBOL(vpe_start);
+
+/* halt it for now */
+int vpe_stop(vpe_handle vpe)
+{
+ struct vpe *v = vpe;
+ struct tc *t;
+ unsigned int evpe_flags;
+
+ evpe_flags = dvpe();
+
+ if ((t = list_entry(v->tc.next, struct tc, tc)) != NULL) {
+
+ settc(t->index);
+ write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~VPECONF0_VPA);
+ }
+
+ evpe(evpe_flags);
+
+ return 0;
+}
+
+EXPORT_SYMBOL(vpe_stop);
+
+/* I've done with it thank you */
+int vpe_free(vpe_handle vpe)
+{
+ struct vpe *v = vpe;
+ struct tc *t;
+ unsigned int evpe_flags;
+
+ if ((t = list_entry(v->tc.next, struct tc, tc)) == NULL) {
+ return -ENOEXEC;
+ }
+
+ evpe_flags = dvpe();
+
+ /* Put MVPE's into 'configuration state' */
+ write_c0_mvpcontrol(read_c0_mvpcontrol() | MVPCONTROL_VPC);
+
+ settc(t->index);
+ write_vpe_c0_vpeconf0(read_vpe_c0_vpeconf0() & ~VPECONF0_VPA);
+
+ /* mark the TC unallocated and halt'ed */
+ write_tc_c0_tcstatus(read_tc_c0_tcstatus() & ~TCSTATUS_A);
+ write_tc_c0_tchalt(TCHALT_H);
+
+ v->state = VPE_STATE_UNUSED;
+
+ write_c0_mvpcontrol(read_c0_mvpcontrol() & ~MVPCONTROL_VPC);
+ evpe(evpe_flags);
+
+ return 0;
+}
+
+EXPORT_SYMBOL(vpe_free);
+
+void *vpe_get_shared(int index)
+{
+ struct vpe *v;
+
+ if ((v = get_vpe(index)) == NULL) {
+ printk(KERN_WARNING "vpe: invalid vpe index %d\n", index);
+ return NULL;
+ }
+
+ return v->shared_ptr;
+}
+
+EXPORT_SYMBOL(vpe_get_shared);
+
+static int __init vpe_module_init(void)
+{
+ struct vpe *v = NULL;
+ struct tc *t;
+ unsigned long val;
+ int i;
+
+ if (!cpu_has_mipsmt) {
+ printk("VPE loader: not a MIPS MT capable processor\n");
+ return -ENODEV;
+ }
+
+ if ((major = register_chrdev(VPE_MAJOR, module_name, &vpe_fops) < 0)) {
+ printk("VPE loader: unable to register character device\n");
+ return -EBUSY;
+ }
+
+ if (major == 0)
+ major = VPE_MAJOR;
+
+ dmt();
+ dvpe();
+
+ /* Put MVPE's into 'configuration state' */
+ write_c0_mvpcontrol(read_c0_mvpcontrol() | MVPCONTROL_VPC);
+
+ /* dump_mtregs(); */
+
+ INIT_LIST_HEAD(&vpecontrol.vpe_list);
+ INIT_LIST_HEAD(&vpecontrol.tc_list);
+
+ val = read_c0_mvpconf0();
+ for (i = 0; i < ((val & MVPCONF0_PTC) + 1); i++) {
+ t = alloc_tc(i);
+
+ /* VPE's */
+ if (i < ((val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT) + 1) {
+ settc(i);
+
+ if ((v = alloc_vpe(i)) == NULL) {
+ printk(KERN_WARNING "VPE: unable to allocate VPE\n");
+ return -ENODEV;
+ }
+
+ list_add(&t->tc, &v->tc); /* add the tc to the list of this vpe's tc's. */
+
+ /* deactivate all but vpe0 */
+ if (i != 0) {
+ unsigned long tmp = read_vpe_c0_vpeconf0();
+
+ tmp &= ~VPECONF0_VPA;
+
+ /* master VPE */
+ tmp |= VPECONF0_MVP;
+ write_vpe_c0_vpeconf0(tmp);
+ }
+
+ /* disable multi-threading with TC's */
+ write_vpe_c0_vpecontrol(read_vpe_c0_vpecontrol() & ~VPECONTROL_TE);
+
+ if (i != 0) {
+ write_vpe_c0_status((read_c0_status() &
+ ~(ST0_IM | ST0_IE | ST0_KSU))
+ | ST0_CU0);
+
+ /* set config to be the same as vpe0, particularly kseg0 coherency alg */
+ write_vpe_c0_config(read_c0_config());
+ }
+
+ }
+
+ /* TC's */
+ t->pvpe = v; /* set the parent vpe */
+
+ if (i != 0) {
+ unsigned long tmp;
+
+ /* tc 0 will of course be running.... */
+ if (i == 0)
+ t->state = TC_STATE_RUNNING;
+
+ settc(i);
+
+ /* bind a TC to each VPE, May as well put all excess TC's
+ on the last VPE */
+ if (i >= (((val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT) + 1))
+ write_tc_c0_tcbind(read_tc_c0_tcbind() |
+ ((val & MVPCONF0_PVPE) >> MVPCONF0_PVPE_SHIFT));
+ else
+ write_tc_c0_tcbind(read_tc_c0_tcbind() | i);
+
+ tmp = read_tc_c0_tcstatus();
+
+ /* mark not allocated and not dynamically allocatable */
+ tmp &= ~(TCSTATUS_A | TCSTATUS_DA);
+ tmp |= TCSTATUS_IXMT; /* interrupt exempt */
+ write_tc_c0_tcstatus(tmp);
+
+ write_tc_c0_tchalt(TCHALT_H);
+ }
+ }
+
+ /* release config state */
+ write_c0_mvpcontrol(read_c0_mvpcontrol() & ~MVPCONTROL_VPC);
+
+ return 0;
+}
+
+static void __exit vpe_module_exit(void)
+{
+ struct vpe *v, *n;
+
+ list_for_each_entry_safe(v, n, &vpecontrol.vpe_list, list) {
+ if (v->state != VPE_STATE_UNUSED) {
+ release_vpe(v);
+ }
+ }
+
+ unregister_chrdev(major, module_name);
+}
+
+module_init(vpe_module_init);
+module_exit(vpe_module_exit);
+MODULE_DESCRIPTION("MIPS VPE Loader");
+MODULE_AUTHOR("Elizabeth Clarke, MIPS Technologies, Inc");
+MODULE_LICENSE("GPL");