/*
* IBM/AMCC PPC4xx SoC setup code
*
* Copyright 2008 DENX Software Engineering, Stefan Roese <sr@denx.de>
*
* L2 cache routines cloned from arch/ppc/syslib/ibm440gx_common.c which is:
* Eugene Surovegin <eugene.surovegin@zultys.com> or <ebs@ebshome.net>
* Copyright (c) 2003 - 2006 Zultys Technologies
*
* 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.
*/
#include <linux/stddef.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/of_platform.h>
#include <asm/dcr.h>
#include <asm/dcr-regs.h>
#include <asm/reg.h>
static u32 dcrbase_l2c;
/*
* L2-cache
*/
/* Issue L2C diagnostic command */
static inline u32 l2c_diag(u32 addr)
{
mtdcr(dcrbase_l2c + DCRN_L2C0_ADDR, addr);
mtdcr(dcrbase_l2c + DCRN_L2C0_CMD, L2C_CMD_DIAG);
while (!(mfdcr(dcrbase_l2c + DCRN_L2C0_SR) & L2C_SR_CC))
;
return mfdcr(dcrbase_l2c + DCRN_L2C0_DATA);
}
static irqreturn_t l2c_error_handler(int irq, void *dev)
{
u32 sr = mfdcr(dcrbase_l2c + DCRN_L2C0_SR);
if (sr & L2C_SR_CPE) {
/* Read cache trapped address */
u32 addr = l2c_diag(0x42000000);
printk(KERN_EMERG "L2C: Cache Parity Error, addr[16:26] = 0x%08x\n",
addr);
}
if (sr & L2C_SR_TPE) {
/* Read tag trapped address */
u32 addr = l2c_diag(0x82000000) >> 16;
printk(KERN_EMERG "L2C: Tag Parity Error, addr[16:26] = 0x%08x\n",
addr);
}
/* Clear parity errors */
if (sr & (L2C_SR_CPE | L2C_SR_TPE)){
mtdcr(dcrbase_l2c + DCRN_L2C0_ADDR, 0);
mtdcr(dcrbase_l2c + DCRN_L2C0_CMD, L2C_CMD_CCP | L2C_CMD_CTE);
} else {
printk(KERN_EMERG "L2C: LRU error\n");
}
return IRQ_HANDLED;
}
static int __init ppc4xx_l2c_probe(void)
{
struct device_node *np;
u32 r;
unsigned long flags;
int irq;
const u32 *dcrreg;
u32 dcrbase_isram;
int len;
const u32 *prop;
u32 l2_size;
np = of_find_compatible_node(NULL, NULL, "ibm,l2-cache");
if (!np)
return 0;
/* Get l2 cache size */
prop = of_get_property(np, "cache-size", NULL);
if (prop == NULL) {
printk(KERN_ERR "%s: Can't get cache-size!\n", np->full_name);
of_node_put(np);
return -ENODEV;
}
l2_size = prop[0];
/* Map DCRs */
dcrreg = of_get_property(np, "dcr-reg", &len);
if (!dcrreg || (len != 4 * sizeof(u32))) {
printk(KERN_ERR "%s: Can't get DCR register base !",
np->full_name);
of_node_put(np);
return -ENODEV;
}
dcrbase_isram = dcrreg[0];
dcrbase_l2c = dcrreg[2];
/* Get and map irq number from device tree */
irq = irq_of_parse_and_map(np, 0);
if (irq == NO_IRQ) {
printk(KERN_ERR "irq_of_parse_and_map failed\n");
of_node_put(np);
return -ENODEV;
}
/* Install error handler */
if (request_irq(irq, l2c_error_handler, IRQF_DISABLED, "L2C", 0) < 0) {
printk(KERN_ERR "Cannot install L2C error handler"
", cache is not enabled\n");
of_node_put(np);
return -ENODEV;
}
local_irq_save(flags);
asm volatile ("sync" ::: "memory");
/* Disable SRAM */
mtdcr(dcrbase_isram + DCRN_SRAM0_DPC,
mfdcr(dcrbase_isram + DCRN_SRAM0_DPC) & ~SRAM_DPC_ENABLE);
mtdcr(dcrbase_isram + DCRN_SRAM0_SB0CR,
mfdcr(dcrbase_isram + DCRN_SRAM0_SB0CR) & ~SRAM_SBCR_BU_MASK);
mtdcr(dcrbase_isram + DCRN_SRAM0_SB1CR,
mfdcr(dcrbase_isram + DCRN_SRAM0_SB1CR) & ~SRAM_SBCR_BU_MASK);
mtdcr(dcrbase_isram + DCRN_SRAM0_SB2CR,
mfdcr(dcrbase_isram + DCRN_SRAM0_SB2CR) & ~SRAM_SBCR_BU_MASK);
mtdcr(dcrbase_isram + DCRN_SRAM0_SB3CR,
mfdcr(dcrbase_isram + DCRN_SRAM0_SB3CR) & ~SRAM_SBCR_BU_MASK);
/* Enable L2_MODE without ICU/DCU */
r = mfdcr(dcrbase_l2c + DCRN_L2C0_CFG) &
~(L2C_CFG_ICU | L2C_CFG_DCU | L2C_CFG_SS_MASK);
r |= L2C_CFG_L2M | L2C_CFG_SS_256;
mtdcr(dcrbase_l2c + DCRN_L2C0_CFG, r);
mtdcr(dcrbase_l2c + DCRN_L2C0_ADDR, 0);
/* Hardware Clear Command */
mtdcr(dcrbase_l2c + DCRN_L2C0_CMD, L2C_CMD_HCC);
while (!(mfdcr(dcrbase_l2c + DCRN_L2C0_SR) & L2C_SR_CC))
;
/* Clear Cache Parity and Tag Errors */
mtdcr(dcrbase_l2c + DCRN_L2C0_CMD, L2C_CMD_CCP | L2C_CMD_CTE);
/* Enable 64G snoop region starting at 0 */
r = mfdcr(dcrbase_l2c + DCRN_L2C0_SNP0) &
~(L2C_SNP_BA_MASK | L2C_SNP_SSR_MASK);
r |= L2C_SNP_SSR_32G | L2C_SNP_ESR;
mtdcr(dcrbase_l2c + DCRN_L2C0_SNP0, r);
r = mfdcr(dcrbase_l2c + DCRN_L2C0_SNP1) &
~(L2C_SNP_BA_MASK | L2C_SNP_SSR_MASK);
r |= 0x80000000 | L2C_SNP_SSR_32G | L2C_SNP_ESR;
mtdcr(dcrbase_l2c + DCRN_L2C0_SNP1, r);
asm volatile ("sync" ::: "memory");
/* Enable ICU/DCU ports */
r = mfdcr(dcrbase_l2c + DCRN_L2C0_CFG);
r &= ~(L2C_CFG_DCW_MASK | L2C_CFG_PMUX_MASK | L2C_CFG_PMIM
| L2C_CFG_TPEI | L2C_CFG_CPEI | L2C_CFG_NAM | L2C_CFG_NBRM);
r |= L2C_CFG_ICU | L2C_CFG_DCU | L2C_CFG_TPC | L2C_CFG_CPC | L2C_CFG_FRAN
| L2C_CFG_CPIM | L2C_CFG_TPIM | L2C_CFG_LIM | L2C_CFG_SMCM;
/* Check for 460EX/GT special handling */
if (of_device_is_compatible(np, "ibm,l2-cache-460ex") ||
of_device_is_compatible(np, "ibm,l2-cache-460gt"))
r |= L2C_CFG_RDBW;
mtdcr(dcrbase_l2c + DCRN_L2C0_CFG, r);
asm volatile ("sync; isync" ::: "memory");
local_irq_restore(flags);
printk(KERN_INFO "%dk L2-cache enabled\n", l2_size >> 10);
of_node_put(np);
return 0;
}
arch_initcall(ppc4xx_l2c_probe);
/*
* Apply a system reset. Alternatively a board specific value may be
* provided via the "reset-type" property in the cpu node.
*/
void ppc4xx_reset_system(char *cmd)
{
struct device_node *np;
u32 reset_type = DBCR0_RST_SYSTEM;
const u32 *prop;
np = of_find_node_by_type(NULL, "cpu");
if (np) {
prop = of_get_property(np, "reset-type", NULL);
/*
* Check if property exists and if it is in range:
* 1 - PPC4xx core reset
* 2 - PPC4xx chip reset
* 3 - PPC4xx system reset (default)
*/
if ((prop) && ((prop[0] >= 1) && (prop[0] <= 3)))
reset_type = prop[0] << 28;
}
mtspr(SPRN_DBCR0, mfspr(SPRN_DBCR0) | reset_type);
while (1)
; /* Just in case the reset doesn't work */
}