| Jayachandran C | 5649d37 | 2013-06-10 06:30:04 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * This file is subject to the terms and conditions of the GNU General Public |
| 3 | * License. See the file "COPYING" in the main directory of this archive |
| 4 | * for more details. |
| 5 | * |
| 6 | * Copyright (C) 2013 Broadcom Corporation. |
| 7 | * |
| 8 | * based on arch/mips/cavium-octeon/cpu.c |
| 9 | * Copyright (C) 2009 Wind River Systems, |
| 10 | * written by Ralf Baechle <ralf@linux-mips.org> |
| 11 | */ |
| 12 | #include <linux/init.h> |
| 13 | #include <linux/irqflags.h> |
| 14 | #include <linux/notifier.h> |
| 15 | #include <linux/prefetch.h> |
| 16 | #include <linux/sched.h> |
| 17 | |
| 18 | #include <asm/cop2.h> |
| 19 | #include <asm/current.h> |
| 20 | #include <asm/mipsregs.h> |
| 21 | #include <asm/page.h> |
| 22 | |
| 23 | #include <asm/netlogic/mips-extns.h> |
| 24 | |
| 25 | /* |
| 26 | * 64 bit ops are done in inline assembly to support 32 bit |
| 27 | * compilation |
| 28 | */ |
| 29 | void nlm_cop2_save(struct nlm_cop2_state *r) |
| 30 | { |
| 31 | asm volatile( |
| 32 | ".set push\n" |
| 33 | ".set noat\n" |
| 34 | "dmfc2 $1, $0, 0\n" |
| 35 | "sd $1, 0(%1)\n" |
| 36 | "dmfc2 $1, $0, 1\n" |
| 37 | "sd $1, 8(%1)\n" |
| 38 | "dmfc2 $1, $0, 2\n" |
| 39 | "sd $1, 16(%1)\n" |
| 40 | "dmfc2 $1, $0, 3\n" |
| 41 | "sd $1, 24(%1)\n" |
| 42 | "dmfc2 $1, $1, 0\n" |
| 43 | "sd $1, 0(%2)\n" |
| 44 | "dmfc2 $1, $1, 1\n" |
| 45 | "sd $1, 8(%2)\n" |
| 46 | "dmfc2 $1, $1, 2\n" |
| 47 | "sd $1, 16(%2)\n" |
| 48 | "dmfc2 $1, $1, 3\n" |
| 49 | "sd $1, 24(%2)\n" |
| 50 | ".set pop\n" |
| 51 | : "=m"(*r) |
| 52 | : "r"(r->tx), "r"(r->rx)); |
| 53 | |
| 54 | r->tx_msg_status = __read_32bit_c2_register($2, 0); |
| 55 | r->rx_msg_status = __read_32bit_c2_register($3, 0) & 0x0fffffff; |
| 56 | } |
| 57 | |
| 58 | void nlm_cop2_restore(struct nlm_cop2_state *r) |
| 59 | { |
| 60 | u32 rstat; |
| 61 | |
| 62 | asm volatile( |
| 63 | ".set push\n" |
| 64 | ".set noat\n" |
| 65 | "ld $1, 0(%1)\n" |
| 66 | "dmtc2 $1, $0, 0\n" |
| 67 | "ld $1, 8(%1)\n" |
| 68 | "dmtc2 $1, $0, 1\n" |
| 69 | "ld $1, 16(%1)\n" |
| 70 | "dmtc2 $1, $0, 2\n" |
| 71 | "ld $1, 24(%1)\n" |
| 72 | "dmtc2 $1, $0, 3\n" |
| 73 | "ld $1, 0(%2)\n" |
| 74 | "dmtc2 $1, $1, 0\n" |
| 75 | "ld $1, 8(%2)\n" |
| 76 | "dmtc2 $1, $1, 1\n" |
| 77 | "ld $1, 16(%2)\n" |
| 78 | "dmtc2 $1, $1, 2\n" |
| 79 | "ld $1, 24(%2)\n" |
| 80 | "dmtc2 $1, $1, 3\n" |
| 81 | ".set pop\n" |
| 82 | : : "m"(*r), "r"(r->tx), "r"(r->rx)); |
| 83 | |
| 84 | __write_32bit_c2_register($2, 0, r->tx_msg_status); |
| 85 | rstat = __read_32bit_c2_register($3, 0) & 0xf0000000u; |
| 86 | __write_32bit_c2_register($3, 0, r->rx_msg_status | rstat); |
| 87 | } |
| 88 | |
| 89 | static int nlm_cu2_call(struct notifier_block *nfb, unsigned long action, |
| 90 | void *data) |
| 91 | { |
| 92 | unsigned long flags; |
| 93 | unsigned int status; |
| 94 | |
| 95 | switch (action) { |
| 96 | case CU2_EXCEPTION: |
| 97 | if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) |
| 98 | break; |
| 99 | local_irq_save(flags); |
| 100 | KSTK_STATUS(current) |= ST0_CU2; |
| 101 | status = read_c0_status(); |
| 102 | write_c0_status(status | ST0_CU2); |
| 103 | nlm_cop2_restore(&(current->thread.cp2)); |
| 104 | write_c0_status(status & ~ST0_CU2); |
| 105 | local_irq_restore(flags); |
| 106 | pr_info("COP2 access enabled for pid %d (%s)\n", |
| 107 | current->pid, current->comm); |
| 108 | return NOTIFY_BAD; /* Don't call default notifier */ |
| 109 | } |
| 110 | |
| 111 | return NOTIFY_OK; /* Let default notifier send signals */ |
| 112 | } |
| 113 | |
| 114 | static int __init nlm_cu2_setup(void) |
| 115 | { |
| 116 | return cu2_notifier(nlm_cu2_call, 0); |
| 117 | } |
| 118 | early_initcall(nlm_cu2_setup); |