| /* 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 LA_REG 0xc8020000 |
| #define FLASH_AUTO_CFG_REG 0xc0006008 |
| |
| /* 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: |
| // Set SPI flash divider to 1 |
| LOAD_IMM64(3, FLASH_AUTO_CFG_REG) |
| lwzcix %r5,0,%r3 |
| lis %r0,0xF |
| andc %r5,%r5,%r0 |
| lis %r4,0x1 |
| or %r5,%r5,%r4 |
| stwcix %r5,0,%r3 |
| |
| // Zero BSS |
| LOAD_IMM64(%r10,__bss_start) |
| LOAD_IMM64(%r11,__bss_end) |
| subf %r11,%r10,%r11 |
| addi %r11,%r11,63 |
| srdi. %r11,%r11,6 |
| beq 2f |
| mtctr %r11 |
| 1: dcbz 0,%r10 |
| addi %r10,%r10,64 |
| bdnz 1b |
| |
| 2: LOAD_IMM64(%r1,__stack_top) |
| li %r0,0 |
| stdu %r0,-16(%r1) |
| LOAD_IMM64(%r12, main) |
| mtctr %r12 |
| bctrl |
| attn // terminate on exit |
| b . |