diff options
Diffstat (limited to 'arch/mips/powertv/powertv_setup.c')
| -rw-r--r-- | arch/mips/powertv/powertv_setup.c | 351 |
1 files changed, 351 insertions, 0 deletions
diff --git a/arch/mips/powertv/powertv_setup.c b/arch/mips/powertv/powertv_setup.c new file mode 100644 index 00000000000..bd8ebf128f2 --- /dev/null +++ b/arch/mips/powertv/powertv_setup.c @@ -0,0 +1,351 @@ +/* + * Carsten Langgaard, carstenl@mips.com + * Copyright (C) 2000 MIPS Technologies, Inc. All rights reserved. + * Portions copyright (C) 2009 Cisco Systems, Inc. + * + * 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. + */ +#include <linux/init.h> +#include <linux/sched.h> +#include <linux/ioport.h> +#include <linux/pci.h> +#include <linux/screen_info.h> +#include <linux/notifier.h> +#include <linux/etherdevice.h> +#include <linux/if_ether.h> +#include <linux/ctype.h> + +#include <linux/cpu.h> +#include <asm/bootinfo.h> +#include <asm/irq.h> +#include <asm/mips-boards/generic.h> +#include <asm/mips-boards/prom.h> +#include <asm/dma.h> +#include <linux/time.h> +#include <asm/traps.h> +#include <asm/asm-offsets.h> +#include "reset.h" + +#define VAL(n) STR(n) + +/* + * Macros for loading addresses and storing registers: + * PTR_LA Load the address into a register + * LONG_S Store the full width of the given register. + * LONG_L Load the full width of the given register + * PTR_ADDIU Add a constant value to a register used as a pointer + * REG_SIZE Number of 8-bit bytes in a full width register + */ +#ifdef CONFIG_64BIT +#warning TODO: 64-bit code needs to be verified +#define PTR_LA "dla " +#define LONG_S "sd " +#define LONG_L "ld " +#define PTR_ADDIU "daddiu " +#define REG_SIZE "8" /* In bytes */ +#endif + +#ifdef CONFIG_32BIT +#define PTR_LA "la " +#define LONG_S "sw " +#define LONG_L "lw " +#define PTR_ADDIU "addiu " +#define REG_SIZE "4" /* In bytes */ +#endif + +static struct pt_regs die_regs; +static bool have_die_regs; + +static void register_panic_notifier(void); +static int panic_handler(struct notifier_block *notifier_block, + unsigned long event, void *cause_string); + +const char *get_system_type(void) +{ + return "PowerTV"; +} + +void __init plat_mem_setup(void) +{ + panic_on_oops = 1; + register_panic_notifier(); + +#if 0 + mips_pcibios_init(); +#endif + mips_reboot_setup(); +} + +/* + * Install a panic notifier for platform-specific diagnostics + */ +static void register_panic_notifier() +{ + static struct notifier_block panic_notifier = { + .notifier_call = panic_handler, + .next = NULL, + .priority = INT_MAX + }; + atomic_notifier_chain_register(&panic_notifier_list, &panic_notifier); +} + +static int panic_handler(struct notifier_block *notifier_block, + unsigned long event, void *cause_string) +{ + struct pt_regs my_regs; + + /* Save all of the registers */ + { + unsigned long at, v0, v1; /* Must be on the stack */ + + /* Start by saving $at and v0 on the stack. We use $at + * ourselves, but it looks like the compiler may use v0 or v1 + * to load the address of the pt_regs structure. We'll come + * back later to store the registers in the pt_regs + * structure. */ + __asm__ __volatile__ ( + ".set noat\n" + LONG_S "$at, %[at]\n" + LONG_S "$2, %[v0]\n" + LONG_S "$3, %[v1]\n" + : + [at] "=m" (at), + [v0] "=m" (v0), + [v1] "=m" (v1) + : + : "at" + ); + + __asm__ __volatile__ ( + ".set noat\n" + "move $at, %[pt_regs]\n" + + /* Argument registers */ + LONG_S "$4, " VAL(PT_R4) "($at)\n" + LONG_S "$5, " VAL(PT_R5) "($at)\n" + LONG_S "$6, " VAL(PT_R6) "($at)\n" + LONG_S "$7, " VAL(PT_R7) "($at)\n" + + /* Temporary regs */ + LONG_S "$8, " VAL(PT_R8) "($at)\n" + LONG_S "$9, " VAL(PT_R9) "($at)\n" + LONG_S "$10, " VAL(PT_R10) "($at)\n" + LONG_S "$11, " VAL(PT_R11) "($at)\n" + LONG_S "$12, " VAL(PT_R12) "($at)\n" + LONG_S "$13, " VAL(PT_R13) "($at)\n" + LONG_S "$14, " VAL(PT_R14) "($at)\n" + LONG_S "$15, " VAL(PT_R15) "($at)\n" + + /* "Saved" registers */ + LONG_S "$16, " VAL(PT_R16) "($at)\n" + LONG_S "$17, " VAL(PT_R17) "($at)\n" + LONG_S "$18, " VAL(PT_R18) "($at)\n" + LONG_S "$19, " VAL(PT_R19) "($at)\n" + LONG_S "$20, " VAL(PT_R20) "($at)\n" + LONG_S "$21, " VAL(PT_R21) "($at)\n" + LONG_S "$22, " VAL(PT_R22) "($at)\n" + LONG_S "$23, " VAL(PT_R23) "($at)\n" + + /* Add'l temp regs */ + LONG_S "$24, " VAL(PT_R24) "($at)\n" + LONG_S "$25, " VAL(PT_R25) "($at)\n" + + /* Kernel temp regs */ + LONG_S "$26, " VAL(PT_R26) "($at)\n" + LONG_S "$27, " VAL(PT_R27) "($at)\n" + + /* Global pointer, stack pointer, frame pointer and + * return address */ + LONG_S "$gp, " VAL(PT_R28) "($at)\n" + LONG_S "$sp, " VAL(PT_R29) "($at)\n" + LONG_S "$fp, " VAL(PT_R30) "($at)\n" + LONG_S "$ra, " VAL(PT_R31) "($at)\n" + + /* Now we can get the $at and v0 registers back and + * store them */ + LONG_L "$8, %[at]\n" + LONG_S "$8, " VAL(PT_R1) "($at)\n" + LONG_L "$8, %[v0]\n" + LONG_S "$8, " VAL(PT_R2) "($at)\n" + LONG_L "$8, %[v1]\n" + LONG_S "$8, " VAL(PT_R3) "($at)\n" + : + : + [at] "m" (at), + [v0] "m" (v0), + [v1] "m" (v1), + [pt_regs] "r" (&my_regs) + : "at", "t0" + ); + + /* Set the current EPC value to be the current location in this + * function */ + __asm__ __volatile__ ( + ".set noat\n" + "1:\n" + PTR_LA "$at, 1b\n" + LONG_S "$at, %[cp0_epc]\n" + : + [cp0_epc] "=m" (my_regs.cp0_epc) + : + : "at" + ); + + my_regs.cp0_cause = read_c0_cause(); + my_regs.cp0_status = read_c0_status(); + } + +#ifdef CONFIG_DIAGNOSTICS + failure_report((char *) cause_string, + have_die_regs ? &die_regs : &my_regs); + have_die_regs = false; +#else + pr_crit("I'm feeling a bit sleepy. hmmmmm... perhaps a nap would... " + "zzzz... \n"); +#endif + + return NOTIFY_DONE; +} + +/** + * Platform-specific handling of oops + * @str: Pointer to the oops string + * @regs: Pointer to the oops registers + * All we do here is to save the registers for subsequent printing through + * the panic notifier. + */ +void platform_die(const char *str, const struct pt_regs *regs) +{ + /* If we already have saved registers, don't overwrite them as they + * they apply to the initial fault */ + + if (!have_die_regs) { + have_die_regs = true; + die_regs = *regs; + } +} + +/* Information about the RF MAC address, if one was supplied on the + * command line. */ +static bool have_rfmac; +static u8 rfmac[ETH_ALEN]; + +static int rfmac_param(char *p) +{ + u8 *q; + bool is_high_nibble; + int c; + + /* Skip a leading "0x", if present */ + if (*p == '0' && *(p+1) == 'x') + p += 2; + + q = rfmac; + is_high_nibble = true; + + for (c = (unsigned char) *p++; + isxdigit(c) && q - rfmac < ETH_ALEN; + c = (unsigned char) *p++) { + int nibble; + + nibble = (isdigit(c) ? (c - '0') : + (isupper(c) ? c - 'A' + 10 : c - 'a' + 10)); + + if (is_high_nibble) + *q = nibble << 4; + else + *q++ |= nibble; + + is_high_nibble = !is_high_nibble; + } + + /* If we parsed all the way to the end of the parameter value and + * parsed all ETH_ALEN bytes, we have a usable RF MAC address */ + have_rfmac = (c == '\0' && q - rfmac == ETH_ALEN); + + return 0; +} + +early_param("rfmac", rfmac_param); + +/* + * Generate an Ethernet MAC address that has a good chance of being unique. + * @addr: Pointer to six-byte array containing the Ethernet address + * Generates an Ethernet MAC address that is highly likely to be unique for + * this particular system on a network with other systems of the same type. + * + * The problem we are solving is that, when random_ether_addr() is used to + * generate MAC addresses at startup, there isn't much entropy for the random + * number generator to use and the addresses it produces are fairly likely to + * be the same as those of other identical systems on the same local network. + * This is true even for relatively small numbers of systems (for the reason + * why, see the Wikipedia entry for "Birthday problem" at: + * http://en.wikipedia.org/wiki/Birthday_problem + * + * The good news is that we already have a MAC address known to be unique, the + * RF MAC address. The bad news is that this address is already in use on the + * RF interface. Worse, the obvious trick, taking the RF MAC address and + * turning on the locally managed bit, has already been used for other devices. + * Still, this does give us something to work with. + * + * The approach we take is: + * 1. If we can't get the RF MAC Address, just call random_ether_addr. + * 2. Use the 24-bit NIC-specific bits of the RF MAC address as the last 24 + * bits of the new address. This is very likely to be unique, except for + * the current box. + * 3. To avoid using addresses already on the current box, we set the top + * six bits of the address with a value different from any currently + * registered Scientific Atlanta organizationally unique identifyer + * (OUI). This avoids duplication with any addresses on the system that + * were generated from valid Scientific Atlanta-registered address by + * simply flipping the locally managed bit. + * 4. We aren't generating a multicast address, so we leave the multicast + * bit off. Since we aren't using a registered address, we have to set + * the locally managed bit. + * 5. We then randomly generate the remaining 16-bits. This does two + * things: + * a. It allows us to call this function for more than one device + * in this system + * b. It ensures that things will probably still work even if + * some device on the device network has a locally managed + * address that matches the top six bits from step 2. + */ +void platform_random_ether_addr(u8 addr[ETH_ALEN]) +{ + const int num_random_bytes = 2; + const unsigned char non_sciatl_oui_bits = 0xc0u; + const unsigned char mac_addr_locally_managed = (1 << 1); + + if (!have_rfmac) { + pr_warning("rfmac not available on command line; " + "generating random MAC address\n"); + random_ether_addr(addr); + } + + else { + int i; + + /* Set the first byte to something that won't match a Scientific + * Atlanta OUI, is locally managed, and isn't a multicast + * address */ + addr[0] = non_sciatl_oui_bits | mac_addr_locally_managed; + + /* Get some bytes of random address information */ + get_random_bytes(&addr[1], num_random_bytes); + + /* Copy over the NIC-specific bits of the RF MAC address */ + for (i = 1 + num_random_bytes; i < ETH_ALEN; i++) + addr[i] = rfmac[i]; + } +} |