diff options
Diffstat (limited to 'arch/i386/cpu/sc520/sc520_car.S')
| -rw-r--r-- | arch/i386/cpu/sc520/sc520_car.S | 93 |
1 files changed, 0 insertions, 93 deletions
diff --git a/arch/i386/cpu/sc520/sc520_car.S b/arch/i386/cpu/sc520/sc520_car.S deleted file mode 100644 index a33f94f..0000000 --- a/arch/i386/cpu/sc520/sc520_car.S +++ /dev/null @@ -1,93 +0,0 @@ -/* - * (C) Copyright 2010-2011 - * Graeme Russ, <graeme.russ@gmail.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> -#include <asm/processor-flags.h> -#include <asm/ic/sc520.h> - -.section .text - -.globl car_init -car_init: - /* - * How to enable Cache-As-RAM for the AMD Elan SC520: - * 1. Turn off the CPU Cache (may not be strictly required) - * 2. Set code execution PAR (usually the BOOTCS region) to be - * non-cachable - * 3. Create a Cachable PAR Region for an area of memory which is - * a) NOT where the code is being executed - * b) NOT SDRAM (Controller not initialised yet) - * c) WILL response to read requests - * The easiest way to do this is to create a second BOOTCS - * PAR mappnig with an address != the PAR in step 2 - * 4. Issue a wbinvd to invalidate the CPU cache - * 5. Turn on the CPU Cache - * 6. Read 16kB from the cached PAR region setup in step 3 - * 7. Turn off the CPU Cache (but DO NOT issue a wbinvd) - * - * The following code uses PAR2 as the cached PAR (PAR0 and PAR1 - * are avoided as these are the only two PARs which can be used - * as PCI BUS Memory regions which the board might require) - * - * The configuration of PAR2 must be set in the board configuration - * file as CONFIG_SYS_SC520_CAR_PAR - */ - - /* Configure Cache-As-RAM PAR */ - movl $CONFIG_SYS_SC520_CAR_PAR, %eax - movl $SC520_PAR2, %edi - movl %eax, (%edi) - - /* Trash the cache then turn it on */ - wbinvd - movl %cr0, %eax - andl $~(X86_CR0_NW | X86_CR0_CD), %eax - movl %eax, %cr0 - - /* - * The cache is now enabled and empty. Map a region of memory to - * it by reading that region. - */ - movl $CONFIG_SYS_CAR_ADDR, %esi - movl $CONFIG_SYS_CAR_SIZE, %ecx - shrl $2, %ecx /* we are reading longs */ - cld - rep lodsl - - /* Turn off the cache, but don't trash it */ - movl %cr0, %eax - orl $(X86_CR0_NW | X86_CR0_CD), %eax - movl %eax, %cr0 - - /* Clear the CAR region */ - xorl %eax, %eax - movl $CONFIG_SYS_CAR_ADDR, %edi - movl $CONFIG_SYS_CAR_SIZE, %ecx - shrl $2, %ecx /* we are writing longs */ - rep stosl - - /* - * Done - We should now have CONFIG_SYS_CAR_SIZE bytes of - * Cache-As-RAM - */ - jmp car_init_ret |