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-rw-r--r--arch/mips/powertv/powertv_setup.c351
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 000000000000..bd8ebf128f29
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+++ b/arch/mips/powertv/powertv_setup.c
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+/*
+ * 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];
+ }
+}
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