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authorAnton Arapov <anton@redhat.com>2012-04-16 10:05:28 +0200
committerAnton Arapov <anton@redhat.com>2012-04-16 10:05:28 +0200
commitb4b6116a13633898cf868f2f103c96a90c4c20f8 (patch)
tree93d1b7e2cfcdf473d8d4ff3ad141fa864f8491f6 /arch/mips/dec/prom
parentedd4be777c953e5faafc80d091d3084b4343f5d3 (diff)
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fedora kernel: d9aad82f3319f3cfd1aebc01234254ef0c37ad84v3.3.2-1
Signed-off-by: Anton Arapov <anton@redhat.com>
Diffstat (limited to 'arch/mips/dec/prom')
-rw-r--r--arch/mips/dec/prom/Makefile9
-rw-r--r--arch/mips/dec/prom/call_o32.S89
-rw-r--r--arch/mips/dec/prom/cmdline.c39
-rw-r--r--arch/mips/dec/prom/console.c45
-rw-r--r--arch/mips/dec/prom/dectypes.h14
-rw-r--r--arch/mips/dec/prom/identify.c186
-rw-r--r--arch/mips/dec/prom/init.c135
-rw-r--r--arch/mips/dec/prom/locore.S29
-rw-r--r--arch/mips/dec/prom/memory.c118
9 files changed, 664 insertions, 0 deletions
diff --git a/arch/mips/dec/prom/Makefile b/arch/mips/dec/prom/Makefile
new file mode 100644
index 00000000000..064ae7a76bd
--- /dev/null
+++ b/arch/mips/dec/prom/Makefile
@@ -0,0 +1,9 @@
+#
+# Makefile for the DECstation prom monitor library routines
+# under Linux.
+#
+
+lib-y += init.o memory.o cmdline.o identify.o console.o
+
+lib-$(CONFIG_32BIT) += locore.o
+lib-$(CONFIG_64BIT) += call_o32.o
diff --git a/arch/mips/dec/prom/call_o32.S b/arch/mips/dec/prom/call_o32.S
new file mode 100644
index 00000000000..8c8498159e4
--- /dev/null
+++ b/arch/mips/dec/prom/call_o32.S
@@ -0,0 +1,89 @@
+/*
+ * O32 interface for the 64 (or N32) ABI.
+ *
+ * Copyright (C) 2002 Maciej W. Rozycki
+ *
+ * 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 <asm/asm.h>
+#include <asm/regdef.h>
+
+/* Maximum number of arguments supported. Must be even! */
+#define O32_ARGC 32
+/* Number of static registers we save. */
+#define O32_STATC 11
+/* Frame size for both of the above. */
+#define O32_FRAMESZ (4 * O32_ARGC + SZREG * O32_STATC)
+
+ .text
+
+/*
+ * O32 function call dispatcher, for interfacing 32-bit ROM routines.
+ *
+ * The standard 64 (N32) calling sequence is supported, with a0
+ * holding a function pointer, a1-a7 -- its first seven arguments
+ * and the stack -- remaining ones (up to O32_ARGC, including a1-a7).
+ * Static registers, gp and fp are preserved, v0 holds a result.
+ * This code relies on the called o32 function for sp and ra
+ * restoration and thus both this dispatcher and the current stack
+ * have to be placed in a KSEGx (or KUSEG) address space. Any
+ * pointers passed have to point to addresses within one of these
+ * spaces as well.
+ */
+NESTED(call_o32, O32_FRAMESZ, ra)
+ REG_SUBU sp,O32_FRAMESZ
+
+ REG_S ra,O32_FRAMESZ-1*SZREG(sp)
+ REG_S fp,O32_FRAMESZ-2*SZREG(sp)
+ REG_S gp,O32_FRAMESZ-3*SZREG(sp)
+ REG_S s7,O32_FRAMESZ-4*SZREG(sp)
+ REG_S s6,O32_FRAMESZ-5*SZREG(sp)
+ REG_S s5,O32_FRAMESZ-6*SZREG(sp)
+ REG_S s4,O32_FRAMESZ-7*SZREG(sp)
+ REG_S s3,O32_FRAMESZ-8*SZREG(sp)
+ REG_S s2,O32_FRAMESZ-9*SZREG(sp)
+ REG_S s1,O32_FRAMESZ-10*SZREG(sp)
+ REG_S s0,O32_FRAMESZ-11*SZREG(sp)
+
+ move jp,a0
+
+ sll a0,a1,zero
+ sll a1,a2,zero
+ sll a2,a3,zero
+ sll a3,a4,zero
+ sw a5,0x10(sp)
+ sw a6,0x14(sp)
+ sw a7,0x18(sp)
+
+ PTR_LA t0,O32_FRAMESZ(sp)
+ PTR_LA t1,0x1c(sp)
+ li t2,O32_ARGC-7
+1:
+ lw t3,(t0)
+ REG_ADDU t0,SZREG
+ sw t3,(t1)
+ REG_SUBU t2,1
+ REG_ADDU t1,4
+ bnez t2,1b
+
+ jalr jp
+
+ REG_L s0,O32_FRAMESZ-11*SZREG(sp)
+ REG_L s1,O32_FRAMESZ-10*SZREG(sp)
+ REG_L s2,O32_FRAMESZ-9*SZREG(sp)
+ REG_L s3,O32_FRAMESZ-8*SZREG(sp)
+ REG_L s4,O32_FRAMESZ-7*SZREG(sp)
+ REG_L s5,O32_FRAMESZ-6*SZREG(sp)
+ REG_L s6,O32_FRAMESZ-5*SZREG(sp)
+ REG_L s7,O32_FRAMESZ-4*SZREG(sp)
+ REG_L gp,O32_FRAMESZ-3*SZREG(sp)
+ REG_L fp,O32_FRAMESZ-2*SZREG(sp)
+ REG_L ra,O32_FRAMESZ-1*SZREG(sp)
+
+ REG_ADDU sp,O32_FRAMESZ
+ jr ra
+END(call_o32)
diff --git a/arch/mips/dec/prom/cmdline.c b/arch/mips/dec/prom/cmdline.c
new file mode 100644
index 00000000000..c3490bebbc5
--- /dev/null
+++ b/arch/mips/dec/prom/cmdline.c
@@ -0,0 +1,39 @@
+/*
+ * cmdline.c: read the command line passed to us by the PROM.
+ *
+ * Copyright (C) 1998 Harald Koerfgen
+ * Copyright (C) 2002, 2004 Maciej W. Rozycki
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/types.h>
+
+#include <asm/bootinfo.h>
+#include <asm/dec/prom.h>
+
+#undef PROM_DEBUG
+
+void __init prom_init_cmdline(s32 argc, s32 *argv, u32 magic)
+{
+ char *arg;
+ int start_arg, i;
+
+ /*
+ * collect args and prepare cmd_line
+ */
+ if (!prom_is_rex(magic))
+ start_arg = 1;
+ else
+ start_arg = 2;
+ for (i = start_arg; i < argc; i++) {
+ arg = (void *)(long)(argv[i]);
+ strcat(arcs_cmdline, arg);
+ if (i < (argc - 1))
+ strcat(arcs_cmdline, " ");
+ }
+
+#ifdef PROM_DEBUG
+ printk("arcs_cmdline: %s\n", &(arcs_cmdline[0]));
+#endif
+}
diff --git a/arch/mips/dec/prom/console.c b/arch/mips/dec/prom/console.c
new file mode 100644
index 00000000000..caa6e047caf
--- /dev/null
+++ b/arch/mips/dec/prom/console.c
@@ -0,0 +1,45 @@
+/*
+ * DECstation PROM-based early console support.
+ *
+ * Copyright (C) 2004, 2007 Maciej W. Rozycki
+ *
+ * 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 <linux/console.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+
+#include <asm/dec/prom.h>
+
+static void __init prom_console_write(struct console *con, const char *s,
+ unsigned int c)
+{
+ char buf[81];
+ unsigned int chunk = sizeof(buf) - 1;
+
+ while (c > 0) {
+ if (chunk > c)
+ chunk = c;
+ memcpy(buf, s, chunk);
+ buf[chunk] = '\0';
+ prom_printf("%s", buf);
+ s += chunk;
+ c -= chunk;
+ }
+}
+
+static struct console promcons __initdata = {
+ .name = "prom",
+ .write = prom_console_write,
+ .flags = CON_BOOT | CON_PRINTBUFFER,
+ .index = -1,
+};
+
+void __init register_prom_console(void)
+{
+ register_console(&promcons);
+}
diff --git a/arch/mips/dec/prom/dectypes.h b/arch/mips/dec/prom/dectypes.h
new file mode 100644
index 00000000000..707b6f1f5a9
--- /dev/null
+++ b/arch/mips/dec/prom/dectypes.h
@@ -0,0 +1,14 @@
+#ifndef DECTYPES
+#define DECTYPES
+
+#define DS2100_3100 1 /* DS2100/3100 Pmax */
+#define DS5000_200 2 /* DS5000/200 3max */
+#define DS5000_1XX 3 /* DS5000/1xx kmin */
+#define DS5000_2X0 4 /* DS5000/2x0 3max+ */
+#define DS5800 5 /* DS5800 Isis */
+#define DS5400 6 /* DS5400 MIPSfair */
+#define DS5000_XX 7 /* DS5000/xx maxine */
+#define DS5500 11 /* DS5500 MIPSfair-2 */
+#define DS5100 12 /* DS5100 MIPSmate */
+
+#endif
diff --git a/arch/mips/dec/prom/identify.c b/arch/mips/dec/prom/identify.c
new file mode 100644
index 00000000000..95e26f4bb38
--- /dev/null
+++ b/arch/mips/dec/prom/identify.c
@@ -0,0 +1,186 @@
+/*
+ * identify.c: machine identification code.
+ *
+ * Copyright (C) 1998 Harald Koerfgen and Paul M. Antoine
+ * Copyright (C) 2002, 2003, 2004, 2005 Maciej W. Rozycki
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/mc146818rtc.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/types.h>
+
+#include <asm/bootinfo.h>
+
+#include <asm/dec/ioasic.h>
+#include <asm/dec/ioasic_addrs.h>
+#include <asm/dec/kn01.h>
+#include <asm/dec/kn02.h>
+#include <asm/dec/kn02ba.h>
+#include <asm/dec/kn02ca.h>
+#include <asm/dec/kn03.h>
+#include <asm/dec/kn230.h>
+#include <asm/dec/prom.h>
+#include <asm/dec/system.h>
+
+#include "dectypes.h"
+
+static const char *dec_system_strings[] = {
+ [MACH_DSUNKNOWN] "unknown DECstation",
+ [MACH_DS23100] "DECstation 2100/3100",
+ [MACH_DS5100] "DECsystem 5100",
+ [MACH_DS5000_200] "DECstation 5000/200",
+ [MACH_DS5000_1XX] "DECstation 5000/1xx",
+ [MACH_DS5000_XX] "Personal DECstation 5000/xx",
+ [MACH_DS5000_2X0] "DECstation 5000/2x0",
+ [MACH_DS5400] "DECsystem 5400",
+ [MACH_DS5500] "DECsystem 5500",
+ [MACH_DS5800] "DECsystem 5800",
+ [MACH_DS5900] "DECsystem 5900",
+};
+
+const char *get_system_type(void)
+{
+#define STR_BUF_LEN 64
+ static char system[STR_BUF_LEN];
+ static int called = 0;
+
+ if (called == 0) {
+ called = 1;
+ snprintf(system, STR_BUF_LEN, "Digital %s",
+ dec_system_strings[mips_machtype]);
+ }
+
+ return system;
+}
+
+
+/*
+ * Setup essential system-specific memory addresses. We need them
+ * early. Semantically the functions belong to prom/init.c, but they
+ * are compact enough we want them inlined. --macro
+ */
+volatile u8 *dec_rtc_base;
+
+EXPORT_SYMBOL(dec_rtc_base);
+
+static inline void prom_init_kn01(void)
+{
+ dec_kn_slot_base = KN01_SLOT_BASE;
+ dec_kn_slot_size = KN01_SLOT_SIZE;
+
+ dec_rtc_base = (void *)CKSEG1ADDR(dec_kn_slot_base + KN01_RTC);
+}
+
+static inline void prom_init_kn230(void)
+{
+ dec_kn_slot_base = KN01_SLOT_BASE;
+ dec_kn_slot_size = KN01_SLOT_SIZE;
+
+ dec_rtc_base = (void *)CKSEG1ADDR(dec_kn_slot_base + KN01_RTC);
+}
+
+static inline void prom_init_kn02(void)
+{
+ dec_kn_slot_base = KN02_SLOT_BASE;
+ dec_kn_slot_size = KN02_SLOT_SIZE;
+ dec_tc_bus = 1;
+
+ dec_rtc_base = (void *)CKSEG1ADDR(dec_kn_slot_base + KN02_RTC);
+}
+
+static inline void prom_init_kn02xa(void)
+{
+ dec_kn_slot_base = KN02XA_SLOT_BASE;
+ dec_kn_slot_size = IOASIC_SLOT_SIZE;
+ dec_tc_bus = 1;
+
+ ioasic_base = (void *)CKSEG1ADDR(dec_kn_slot_base + IOASIC_IOCTL);
+ dec_rtc_base = (void *)CKSEG1ADDR(dec_kn_slot_base + IOASIC_TOY);
+}
+
+static inline void prom_init_kn03(void)
+{
+ dec_kn_slot_base = KN03_SLOT_BASE;
+ dec_kn_slot_size = IOASIC_SLOT_SIZE;
+ dec_tc_bus = 1;
+
+ ioasic_base = (void *)CKSEG1ADDR(dec_kn_slot_base + IOASIC_IOCTL);
+ dec_rtc_base = (void *)CKSEG1ADDR(dec_kn_slot_base + IOASIC_TOY);
+}
+
+
+void __init prom_identify_arch(u32 magic)
+{
+ unsigned char dec_cpunum, dec_firmrev, dec_etc, dec_systype;
+ u32 dec_sysid;
+
+ if (!prom_is_rex(magic)) {
+ dec_sysid = simple_strtoul(prom_getenv("systype"),
+ (char **)0, 0);
+ } else {
+ dec_sysid = rex_getsysid();
+ if (dec_sysid == 0) {
+ printk("Zero sysid returned from PROM! "
+ "Assuming a PMAX-like machine.\n");
+ dec_sysid = 1;
+ }
+ }
+
+ dec_cpunum = (dec_sysid & 0xff000000) >> 24;
+ dec_systype = (dec_sysid & 0xff0000) >> 16;
+ dec_firmrev = (dec_sysid & 0xff00) >> 8;
+ dec_etc = dec_sysid & 0xff;
+
+ /*
+ * FIXME: This may not be an exhaustive list of DECStations/Servers!
+ * Put all model-specific initialisation calls here.
+ */
+ switch (dec_systype) {
+ case DS2100_3100:
+ mips_machtype = MACH_DS23100;
+ prom_init_kn01();
+ break;
+ case DS5100: /* DS5100 MIPSMATE */
+ mips_machtype = MACH_DS5100;
+ prom_init_kn230();
+ break;
+ case DS5000_200: /* DS5000 3max */
+ mips_machtype = MACH_DS5000_200;
+ prom_init_kn02();
+ break;
+ case DS5000_1XX: /* DS5000/100 3min */
+ mips_machtype = MACH_DS5000_1XX;
+ prom_init_kn02xa();
+ break;
+ case DS5000_2X0: /* DS5000/240 3max+ or DS5900 bigmax */
+ mips_machtype = MACH_DS5000_2X0;
+ prom_init_kn03();
+ if (!(ioasic_read(IO_REG_SIR) & KN03_IO_INR_3MAXP))
+ mips_machtype = MACH_DS5900;
+ break;
+ case DS5000_XX: /* Personal DS5000/xx maxine */
+ mips_machtype = MACH_DS5000_XX;
+ prom_init_kn02xa();
+ break;
+ case DS5800: /* DS5800 Isis */
+ mips_machtype = MACH_DS5800;
+ break;
+ case DS5400: /* DS5400 MIPSfair */
+ mips_machtype = MACH_DS5400;
+ break;
+ case DS5500: /* DS5500 MIPSfair-2 */
+ mips_machtype = MACH_DS5500;
+ break;
+ default:
+ mips_machtype = MACH_DSUNKNOWN;
+ break;
+ }
+
+ if (mips_machtype == MACH_DSUNKNOWN)
+ printk("This is an %s, id is %x\n",
+ dec_system_strings[mips_machtype], dec_systype);
+ else
+ printk("This is a %s\n", dec_system_strings[mips_machtype]);
+}
diff --git a/arch/mips/dec/prom/init.c b/arch/mips/dec/prom/init.c
new file mode 100644
index 00000000000..93f1239af52
--- /dev/null
+++ b/arch/mips/dec/prom/init.c
@@ -0,0 +1,135 @@
+/*
+ * init.c: PROM library initialisation code.
+ *
+ * Copyright (C) 1998 Harald Koerfgen
+ * Copyright (C) 2002, 2004 Maciej W. Rozycki
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/linkage.h>
+#include <linux/smp.h>
+#include <linux/string.h>
+#include <linux/types.h>
+
+#include <asm/bootinfo.h>
+#include <asm/cpu.h>
+#include <asm/processor.h>
+
+#include <asm/dec/prom.h>
+
+
+int (*__rex_bootinit)(void);
+int (*__rex_bootread)(void);
+int (*__rex_getbitmap)(memmap *);
+unsigned long *(*__rex_slot_address)(int);
+void *(*__rex_gettcinfo)(void);
+int (*__rex_getsysid)(void);
+void (*__rex_clear_cache)(void);
+
+int (*__prom_getchar)(void);
+char *(*__prom_getenv)(char *);
+int (*__prom_printf)(char *, ...);
+
+int (*__pmax_open)(char*, int);
+int (*__pmax_lseek)(int, long, int);
+int (*__pmax_read)(int, void *, int);
+int (*__pmax_close)(int);
+
+
+/*
+ * Detect which PROM the DECSTATION has, and set the callback vectors
+ * appropriately.
+ */
+void __init which_prom(s32 magic, s32 *prom_vec)
+{
+ /*
+ * No sign of the REX PROM's magic number means we assume a non-REX
+ * machine (i.e. we're on a DS2100/3100, DS5100 or DS5000/2xx)
+ */
+ if (prom_is_rex(magic)) {
+ /*
+ * Set up prom abstraction structure with REX entry points.
+ */
+ __rex_bootinit =
+ (void *)(long)*(prom_vec + REX_PROM_BOOTINIT);
+ __rex_bootread =
+ (void *)(long)*(prom_vec + REX_PROM_BOOTREAD);
+ __rex_getbitmap =
+ (void *)(long)*(prom_vec + REX_PROM_GETBITMAP);
+ __prom_getchar =
+ (void *)(long)*(prom_vec + REX_PROM_GETCHAR);
+ __prom_getenv =
+ (void *)(long)*(prom_vec + REX_PROM_GETENV);
+ __rex_getsysid =
+ (void *)(long)*(prom_vec + REX_PROM_GETSYSID);
+ __rex_gettcinfo =
+ (void *)(long)*(prom_vec + REX_PROM_GETTCINFO);
+ __prom_printf =
+ (void *)(long)*(prom_vec + REX_PROM_PRINTF);
+ __rex_slot_address =
+ (void *)(long)*(prom_vec + REX_PROM_SLOTADDR);
+ __rex_clear_cache =
+ (void *)(long)*(prom_vec + REX_PROM_CLEARCACHE);
+ } else {
+ /*
+ * Set up prom abstraction structure with non-REX entry points.
+ */
+ __prom_getchar = (void *)PMAX_PROM_GETCHAR;
+ __prom_getenv = (void *)PMAX_PROM_GETENV;
+ __prom_printf = (void *)PMAX_PROM_PRINTF;
+ __pmax_open = (void *)PMAX_PROM_OPEN;
+ __pmax_lseek = (void *)PMAX_PROM_LSEEK;
+ __pmax_read = (void *)PMAX_PROM_READ;
+ __pmax_close = (void *)PMAX_PROM_CLOSE;
+ }
+}
+
+void __init prom_init(void)
+{
+ extern void dec_machine_halt(void);
+ static char cpu_msg[] __initdata =
+ "Sorry, this kernel is compiled for a wrong CPU type!\n";
+ s32 argc = fw_arg0;
+ s32 *argv = (void *)fw_arg1;
+ u32 magic = fw_arg2;
+ s32 *prom_vec = (void *)fw_arg3;
+
+ /*
+ * Determine which PROM we have
+ * (and therefore which machine we're on!)
+ */
+ which_prom(magic, prom_vec);
+
+ if (prom_is_rex(magic))
+ rex_clear_cache();
+
+ /* Register the early console. */
+ register_prom_console();
+
+ /* Were we compiled with the right CPU option? */
+#if defined(CONFIG_CPU_R3000)
+ if ((current_cpu_type() == CPU_R4000SC) ||
+ (current_cpu_type() == CPU_R4400SC)) {
+ static char r4k_msg[] __initdata =
+ "Please recompile with \"CONFIG_CPU_R4x00 = y\".\n";
+ printk(cpu_msg);
+ printk(r4k_msg);
+ dec_machine_halt();
+ }
+#endif
+
+#if defined(CONFIG_CPU_R4X00)
+ if ((current_cpu_type() == CPU_R3000) ||
+ (current_cpu_type() == CPU_R3000A)) {
+ static char r3k_msg[] __initdata =
+ "Please recompile with \"CONFIG_CPU_R3000 = y\".\n";
+ printk(cpu_msg);
+ printk(r3k_msg);
+ dec_machine_halt();
+ }
+#endif
+
+ prom_meminit(magic);
+ prom_identify_arch(magic);
+ prom_init_cmdline(argc, argv, magic);
+}
diff --git a/arch/mips/dec/prom/locore.S b/arch/mips/dec/prom/locore.S
new file mode 100644
index 00000000000..f72b5741025
--- /dev/null
+++ b/arch/mips/dec/prom/locore.S
@@ -0,0 +1,29 @@
+/*
+ * locore.S
+ */
+#include <asm/asm.h>
+#include <asm/regdef.h>
+#include <asm/mipsregs.h>
+
+ .text
+
+/*
+ * Simple general exception handling routine. This one is used for the
+ * Memory sizing routine for pmax machines. HK
+ */
+
+NESTED(genexcept_early, 0, sp)
+ .set noat
+ .set noreorder
+
+ mfc0 k0, CP0_STATUS
+ la k1, mem_err
+
+ sw k0, 0(k1)
+
+ mfc0 k0, CP0_EPC
+ nop
+ addiu k0, 4 # skip the causing instruction
+ jr k0
+ rfe
+END(genexcept_early)
diff --git a/arch/mips/dec/prom/memory.c b/arch/mips/dec/prom/memory.c
new file mode 100644
index 00000000000..e95ff3054ff
--- /dev/null
+++ b/arch/mips/dec/prom/memory.c
@@ -0,0 +1,118 @@
+/*
+ * memory.c: memory initialisation code.
+ *
+ * Copyright (C) 1998 Harald Koerfgen, Frieder Streffer and Paul M. Antoine
+ * Copyright (C) 2000, 2002 Maciej W. Rozycki
+ */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/bootmem.h>
+#include <linux/types.h>
+
+#include <asm/addrspace.h>
+#include <asm/bootinfo.h>
+#include <asm/dec/machtype.h>
+#include <asm/dec/prom.h>
+#include <asm/page.h>
+#include <asm/sections.h>
+
+
+volatile unsigned long mem_err; /* So we know an error occurred */
+
+/*
+ * Probe memory in 4MB chunks, waiting for an error to tell us we've fallen
+ * off the end of real memory. Only suitable for the 2100/3100's (PMAX).
+ */
+
+#define CHUNK_SIZE 0x400000
+
+static inline void pmax_setup_memory_region(void)
+{
+ volatile unsigned char *memory_page, dummy;
+ char old_handler[0x80];
+ extern char genexcept_early;
+
+ /* Install exception handler */
+ memcpy(&old_handler, (void *)(CKSEG0 + 0x80), 0x80);
+ memcpy((void *)(CKSEG0 + 0x80), &genexcept_early, 0x80);
+
+ /* read unmapped and uncached (KSEG1)
+ * DECstations have at least 4MB RAM
+ * Assume less than 480MB of RAM, as this is max for 5000/2xx
+ * FIXME this should be replaced by the first free page!
+ */
+ for (memory_page = (unsigned char *)CKSEG1 + CHUNK_SIZE;
+ mem_err == 0 && memory_page < (unsigned char *)CKSEG1 + 0x1e00000;
+ memory_page += CHUNK_SIZE) {
+ dummy = *memory_page;
+ }
+ memcpy((void *)(CKSEG0 + 0x80), &old_handler, 0x80);
+
+ add_memory_region(0, (unsigned long)memory_page - CKSEG1 - CHUNK_SIZE,
+ BOOT_MEM_RAM);
+}
+
+/*
+ * Use the REX prom calls to get hold of the memory bitmap, and thence
+ * determine memory size.
+ */
+static inline void rex_setup_memory_region(void)
+{
+ int i, bitmap_size;
+ unsigned long mem_start = 0, mem_size = 0;
+ memmap *bm;
+
+ /* some free 64k */
+ bm = (memmap *)CKSEG0ADDR(0x28000);
+
+ bitmap_size = rex_getbitmap(bm);
+
+ for (i = 0; i < bitmap_size; i++) {
+ /* FIXME: very simplistically only add full sets of pages */
+ if (bm->bitmap[i] == 0xff)
+ mem_size += (8 * bm->pagesize);
+ else if (!mem_size)
+ mem_start += (8 * bm->pagesize);
+ else {
+ add_memory_region(mem_start, mem_size, BOOT_MEM_RAM);
+ mem_start += mem_size + (8 * bm->pagesize);
+ mem_size = 0;
+ }
+ }
+ if (mem_size)
+ add_memory_region(mem_start, mem_size, BOOT_MEM_RAM);
+}
+
+void __init prom_meminit(u32 magic)
+{
+ if (!prom_is_rex(magic))
+ pmax_setup_memory_region();
+ else
+ rex_setup_memory_region();
+}
+
+void __init prom_free_prom_memory(void)
+{
+ unsigned long end;
+
+ /*
+ * Free everything below the kernel itself but leave
+ * the first page reserved for the exception handlers.
+ */
+
+#if defined(CONFIG_DECLANCE) || defined(CONFIG_DECLANCE_MODULE)
+ /*
+ * Leave 128 KB reserved for Lance memory for
+ * IOASIC DECstations.
+ *
+ * XXX: save this address for use in dec_lance.c?
+ */
+ if (IOASIC)
+ end = __pa(&_text) - 0x00020000;
+ else
+#endif
+ end = __pa(&_text);
+
+ free_init_pages("unused PROM memory", PAGE_SIZE, end);
+}