| /* Copyright 2013-2014 IBM Corp. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or |
| * implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #define GPIO_BASE 0xc0007000 |
| #define GPIO_OUT 0x0 |
| #define GPIO_DIR 0x8 |
| |
| #define GPIO_MICROWATT_SUCCESS 0x00d5 |
| |
| /* Load an immediate 64-bit value into a register */ |
| #define LOAD_IMM64(r, e) \ |
| lis r,(e)@highest; \ |
| ori r,r,(e)@higher; \ |
| rldicr r,r, 32, 31; \ |
| oris r,r, (e)@h; \ |
| ori r,r, (e)@l; |
| |
| .section ".head","ax" |
| .global _start |
| _start: |
| LOAD_IMM64(%r3, GPIO_BASE) |
| |
| addi %r4,%r3,GPIO_DIR |
| li %r5,-1 |
| rldicl %r5,%r5,0,48 // 16 bits output, 16 bits input |
| stwcix %r5,0,%r4 |
| |
| addi %r4,%r3,GPIO_OUT |
| LOAD_IMM64(%r5, GPIO_MICROWATT_SUCCESS) |
| stwcix %r5,0,%r4 |
| |
| 1: b 1b |