| /* |
| * (C) Copyright 2001 |
| * Erik Theisen, Wave 7 Optics, etheisen@mindspring.com |
| * |
| * See file CREDITS for list of people who contributed to this |
| * project. |
| * |
| * 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. |
| * |
| * This program is distributed in the hope that 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 <config.h> |
| |
| #if defined(CONFIG_4xx) && defined(CONFIG_CMD_SETGETDCR) |
| |
| #include <asm/ppc4xx.h> |
| |
| #define _LINUX_CONFIG_H 1 /* avoid reading Linux autoconf.h file */ |
| |
| #include <ppc_asm.tmpl> |
| #include <ppc_defs.h> |
| |
| #include <asm/cache.h> |
| #include <asm/mmu.h> |
| |
| #define _ASMLANGUAGE |
| |
| /***************************************************************************** |
| * |
| * XXX - DANGER |
| * These routines make use of self modifying code. DO NOT CALL THEM |
| * UNTIL THEY ARE RELOCATED TO RAM. Additionally, I do not |
| * recommend them for use in anything other than an interactive |
| * debugging environment. This is mainly due to performance reasons. |
| * |
| ****************************************************************************/ |
| |
| /* |
| * static void _create_MFDCR(unsigned short dcrn) |
| * |
| * Builds a 'mfdcr' instruction for get_dcr |
| * function. |
| */ |
| .section ".text" |
| .align 2 |
| .type _create_MFDCR,@function |
| _create_MFDCR: |
| /* |
| * Build up a 'mfdcr' instruction formatted as follows: |
| * |
| * OPCD | RT | DCRF | XO | CR | |
| * ---------------|--------------|--------------|----| |
| * 0 5 | 6 10 | 11 20 | 21 30 | 31 | |
| * | | DCRN | | | |
| * 31 | %r3 | (5..9|0..4) | 323 | 0 | |
| * |
| * Where: |
| * OPCD = opcode - 31 |
| * RT = destination register - %r3 return register |
| * DCRF = DCRN # with upper and lower halves swapped |
| * XO = extended opcode - 323 |
| * CR = CR[CR0] NOT undefined - 0 |
| */ |
| rlwinm r0, r3, 27, 27, 31 /* OPCD = 31 */ |
| rlwinm r3, r3, 5, 22, 26 |
| or r3, r3, r0 |
| slwi r3, r3, 10 |
| oris r3, r3, 0x3e30 /* RT = %r3 */ |
| ori r3, r3, 323 /* XO = 323 */ |
| slwi r3, r3, 1 /* CR = 0 */ |
| |
| mflr r4 |
| stw r3, 0(r4) /* Store instr in get_dcr() */ |
| dcbst r0, r4 /* Make sure val is written out */ |
| sync /* Wait for write to complete */ |
| icbi r0, r4 /* Make sure old instr is dumped */ |
| isync /* Wait for icbi to complete */ |
| |
| blr |
| .Lfe1: .size _create_MFDCR,.Lfe1-_create_MFDCR |
| /* end _create_MFDCR() */ |
| |
| /* |
| * static void _create_MTDCR(unsigned short dcrn, unsigned long value) |
| * |
| * Builds a 'mtdcr' instruction for set_dcr |
| * function. |
| */ |
| .section ".text" |
| .align 2 |
| .type _create_MTDCR,@function |
| _create_MTDCR: |
| /* |
| * Build up a 'mtdcr' instruction formatted as follows: |
| * |
| * OPCD | RS | DCRF | XO | CR | |
| * ---------------|--------------|--------------|----| |
| * 0 5 | 6 10 | 11 20 | 21 30 | 31 | |
| * | | DCRN | | | |
| * 31 | %r3 | (5..9|0..4) | 451 | 0 | |
| * |
| * Where: |
| * OPCD = opcode - 31 |
| * RS = source register - %r4 |
| * DCRF = dest. DCRN # with upper and lower halves swapped |
| * XO = extended opcode - 451 |
| * CR = CR[CR0] NOT undefined - 0 |
| */ |
| rlwinm r0, r3, 27, 27, 31 /* OPCD = 31 */ |
| rlwinm r3, r3, 5, 22, 26 |
| or r3, r3, r0 |
| slwi r3, r3, 10 |
| oris r3, r3, 0x3e40 /* RS = %r4 */ |
| ori r3, r3, 451 /* XO = 451 */ |
| slwi r3, r3, 1 /* CR = 0 */ |
| |
| mflr r5 |
| stw r3, 0(r5) /* Store instr in set_dcr() */ |
| dcbst r0, r5 /* Make sure val is written out */ |
| sync /* Wait for write to complete */ |
| icbi r0, r5 /* Make sure old instr is dumped */ |
| isync /* Wait for icbi to complete */ |
| |
| blr |
| .Lfe2: .size _create_MTDCR,.Lfe2-_create_MTDCR |
| /* end _create_MTDCR() */ |
| |
| |
| /* |
| * unsigned long get_dcr(unsigned short dcrn) |
| * |
| * Return a given DCR's value. |
| */ |
| /* */ |
| /* XXX - This is self modifying code, hence */ |
| /* it is in the data section. */ |
| /* */ |
| .section ".data" |
| .align 2 |
| .globl get_dcr |
| .type get_dcr,@function |
| get_dcr: |
| mflr r0 /* Get link register */ |
| stwu r1, -32(r1) /* Save back chain and move SP */ |
| stw r0, +36(r1) /* Save link register */ |
| |
| bl _create_MFDCR /* Build following instruction */ |
| /* XXX - we build this instuction up on the fly. */ |
| .long 0 /* Get DCR's value */ |
| |
| lwz r0, +36(r1) /* Get saved link register */ |
| mtlr r0 /* Restore link register */ |
| addi r1, r1, +32 /* Remove frame from stack */ |
| blr /* Return to calling function */ |
| .Lfe3: .size get_dcr,.Lfe3-get_dcr |
| /* end get_dcr() */ |
| |
| |
| /* |
| * unsigned void set_dcr(unsigned short dcrn, unsigned long value) |
| * |
| * Return a given DCR's value. |
| */ |
| /* |
| * XXX - This is self modifying code, hence |
| * it is in the data section. |
| */ |
| .section ".data" |
| .align 2 |
| .globl set_dcr |
| .type set_dcr,@function |
| set_dcr: |
| mflr r0 /* Get link register */ |
| stwu r1, -32(r1) /* Save back chain and move SP */ |
| stw r0, +36(r1) /* Save link register */ |
| |
| bl _create_MTDCR /* Build following instruction */ |
| /* XXX - we build this instuction up on the fly. */ |
| .long 0 /* Set DCR's value */ |
| |
| lwz r0, +36(r1) /* Get saved link register */ |
| mtlr r0 /* Restore link register */ |
| addi r1, r1, +32 /* Remove frame from stack */ |
| blr /* Return to calling function */ |
| .Lfe4: .size set_dcr,.Lfe4-set_dcr |
| /* end set_dcr() */ |
| #endif |
