[PATCH 1/2] [POWERPC] Add PPC4xx L2-cache support (440GX & 460EX/GT)

Stefan Roese

2008-03-18 13:36:29 UTC

This patch adds support for the 256k L2 cache found on some IBM/AMCC
4xx PPC's. It introduces a common 4xx SoC file (sysdev/ppc4xx_soc.c)
which currently "only" adds the L2 cache init code. Other common 4xx
stuff can be added later here.

The L2 cache handling code is just a copy of Eugene's code in arch/ppc
with small modifications.

Tested on AMCC Taishan 440GX and Canyonlands 460EX.

Signed-off-by: Stefan Roese <sr at denx.de>
---
arch/powerpc/Kconfig | 3 +
arch/powerpc/platforms/44x/Kconfig | 2 +
arch/powerpc/sysdev/Makefile | 1 +
arch/powerpc/sysdev/ppc4xx_soc.c | 174 ++++++++++++++++++++++++++++++++++++
include/asm-powerpc/dcr-regs.h | 78 ++++++++++++++++
5 files changed, 258 insertions(+), 0 deletions(-)
create mode 100644 arch/powerpc/sysdev/ppc4xx_soc.c

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 1189d8d..69d4738 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -490,6 +490,9 @@ config FSL_PCI
bool
select PPC_INDIRECT_PCI

+config 4xx_SOC
+ bool
+
# Yes MCA RS/6000s exist but Linux-PPC does not currently support any
config MCA
bool
diff --git a/arch/powerpc/platforms/44x/Kconfig b/arch/powerpc/platforms/44x/Kconfig
index 83155fe..061ba3c 100644
--- a/arch/powerpc/platforms/44x/Kconfig
+++ b/arch/powerpc/platforms/44x/Kconfig
@@ -120,6 +120,7 @@ config 440GP

config 440GX
bool
+ select 4xx_SOC
select IBM_NEW_EMAC_EMAC4
select IBM_NEW_EMAC_RGMII
select IBM_NEW_EMAC_ZMII #test only
diff --git a/arch/powerpc/sysdev/Makefile b/arch/powerpc/sysdev/Makefile
index 15f3e85..851a0be 100644
--- a/arch/powerpc/sysdev/Makefile
+++ b/arch/powerpc/sysdev/Makefile
@@ -27,6 +27,7 @@ obj-$(CONFIG_PPC_INDIRECT_PCI) += indirect_pci.o
obj-$(CONFIG_PPC_I8259) += i8259.o
obj-$(CONFIG_IPIC) += ipic.o
obj-$(CONFIG_4xx) += uic.o
+obj-$(CONFIG_4xx_SOC) += ppc4xx_soc.o
obj-$(CONFIG_XILINX_VIRTEX) += xilinx_intc.o
obj-$(CONFIG_OF_RTC) += of_rtc.o
ifeq ($(CONFIG_PCI),y)
diff --git a/arch/powerpc/sysdev/ppc4xx_soc.c b/arch/powerpc/sysdev/ppc4xx_soc.c
new file mode 100644
index 0000000..4847555
--- /dev/null
+++ b/arch/powerpc/sysdev/ppc4xx_soc.c
@@ -0,0 +1,174 @@
+/*
+ * IBM/AMCC PPC4xx SoC setup code
+ *
+ * Copyright 2008 DENX Software Engineering, Stefan Roese <sr at denx.de>
+ *
+ * L2 cache routines cloned from arch/ppc/syslib/ibm440gx_common.c which is:
+ * Eugene Surovegin <eugene.surovegin at zultys.com> or <ebs at 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>
+
+static u32 dcrbase;
+
+/*
+ * L2-cache
+ */
+
+/* Issue L2C diagnostic command */
+static inline u32 l2c_diag(u32 addr)
+{
+ mtdcr(dcrbase + DCRN_L2C0_ADDR, addr);
+ mtdcr(dcrbase + DCRN_L2C0_CMD, L2C_CMD_DIAG);
+ while (!(mfdcr(dcrbase + DCRN_L2C0_SR) & L2C_SR_CC))
+ ;
+
+ return mfdcr(dcrbase + DCRN_L2C0_DATA);
+}
+
+static irqreturn_t l2c_error_handler(int irq, void *dev)
+{
+ u32 sr = mfdcr(dcrbase + 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 + DCRN_L2C0_ADDR, 0);
+ mtdcr(dcrbase + 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 = NULL;
+ u32 r;
+ unsigned long flags;
+ int irq;
+ const u32 *dcrreg;
+ u32 dcrbase_isram;
+ int len;
+
+ np = of_find_compatible_node(np, NULL, "ibm,l2-cache");
+ if (!np)
+ return 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);
+ return -ENODEV;
+ }
+ dcrbase_isram = dcrreg[0];
+ dcrbase = 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");
+ 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");
+ 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 + DCRN_L2C0_CFG) &
+ ~(L2C_CFG_ICU | L2C_CFG_DCU | L2C_CFG_SS_MASK);
+ r |= L2C_CFG_L2M | L2C_CFG_SS_256;
+ mtdcr(dcrbase + DCRN_L2C0_CFG, r);
+
+ mtdcr(dcrbase + DCRN_L2C0_ADDR, 0);
+
+ /* Hardware Clear Command */
+ mtdcr(dcrbase + DCRN_L2C0_CMD, L2C_CMD_HCC);
+ while (!(mfdcr(dcrbase + DCRN_L2C0_SR) & L2C_SR_CC))
+ ;
+
+ /* Clear Cache Parity and Tag Errors */
+ mtdcr(dcrbase + DCRN_L2C0_CMD, L2C_CMD_CCP | L2C_CMD_CTE);
+
+ /* Enable 64G snoop region starting at 0 */
+ r = mfdcr(dcrbase + DCRN_L2C0_SNP0) &
+ ~(L2C_SNP_BA_MASK | L2C_SNP_SSR_MASK);
+ r |= L2C_SNP_SSR_32G | L2C_SNP_ESR;
+ mtdcr(dcrbase + DCRN_L2C0_SNP0, r);
+
+ r = mfdcr(dcrbase + DCRN_L2C0_SNP1) &
+ ~(L2C_SNP_BA_MASK | L2C_SNP_SSR_MASK);
+ r |= 0x80000000 | L2C_SNP_SSR_32G | L2C_SNP_ESR;
+ mtdcr(dcrbase + DCRN_L2C0_SNP1, r);
+
+ asm volatile ("sync" ::: "memory");
+
+ /* Enable ICU/DCU ports */
+ r = mfdcr(dcrbase + 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"))
+ r |= L2C_CFG_RDBW;
+
+ mtdcr(dcrbase + DCRN_L2C0_CFG, r);
+
+ asm volatile ("sync; isync" ::: "memory");
+ local_irq_restore(flags);
+
+ printk(KERN_INFO "256k L2-cache enabled\n");
+
+ return 0;
+}
+arch_initcall(ppc4xx_l2c_probe);
diff --git a/include/asm-powerpc/dcr-regs.h b/include/asm-powerpc/dcr-regs.h
index 9f1fb98..29b0ece 100644
--- a/include/asm-powerpc/dcr-regs.h
+++ b/include/asm-powerpc/dcr-regs.h
@@ -68,4 +68,82 @@
#define SDR0_UART3 0x0123
#define SDR0_CUST0 0x4000

+/*
+ * All those DCR register addresses are offsets from the base address
+ * for the SRAM0 controller (e.g. 0x20 on 440GX). The base address is
+ * excluded here and configured in the device tree.
+ */
+#define DCRN_SRAM0_SB0CR 0x00
+#define DCRN_SRAM0_SB1CR 0x01
+#define DCRN_SRAM0_SB2CR 0x02
+#define DCRN_SRAM0_SB3CR 0x03
+#define SRAM_SBCR_BU_MASK 0x00000180
+#define SRAM_SBCR_BS_64KB 0x00000800
+#define SRAM_SBCR_BU_RO 0x00000080
+#define SRAM_SBCR_BU_RW 0x00000180
+#define DCRN_SRAM0_BEAR 0x04
+#define DCRN_SRAM0_BESR0 0x05
+#define DCRN_SRAM0_BESR1 0x06
+#define DCRN_SRAM0_PMEG 0x07
+#define DCRN_SRAM0_CID 0x08
+#define DCRN_SRAM0_REVID 0x09
+#define DCRN_SRAM0_DPC 0x0a
+#define SRAM_DPC_ENABLE 0x80000000
+
+/*
+ * All those DCR register addresses are offsets from the base address
+ * for the SRAM0 controller (e.g. 0x30 on 440GX). The base address is
+ * excluded here and configured in the device tree.
+ */
+#define DCRN_L2C0_CFG 0x00
+#define L2C_CFG_L2M 0x80000000
+#define L2C_CFG_ICU 0x40000000
+#define L2C_CFG_DCU 0x20000000
+#define L2C_CFG_DCW_MASK 0x1e000000
+#define L2C_CFG_TPC 0x01000000
+#define L2C_CFG_CPC 0x00800000
+#define L2C_CFG_FRAN 0x00200000
+#define L2C_CFG_SS_MASK 0x00180000
+#define L2C_CFG_SS_256 0x00000000
+#define L2C_CFG_CPIM 0x00040000
+#define L2C_CFG_TPIM 0x00020000
+#define L2C_CFG_LIM 0x00010000
+#define L2C_CFG_PMUX_MASK 0x00007000
+#define L2C_CFG_PMUX_SNP 0x00000000
+#define L2C_CFG_PMUX_IF 0x00001000
+#define L2C_CFG_PMUX_DF 0x00002000
+#define L2C_CFG_PMUX_DS 0x00003000
+#define L2C_CFG_PMIM 0x00000800
+#define L2C_CFG_TPEI 0x00000400
+#define L2C_CFG_CPEI 0x00000200
+#define L2C_CFG_NAM 0x00000100
+#define L2C_CFG_SMCM 0x00000080
+#define L2C_CFG_NBRM 0x00000040
+#define L2C_CFG_RDBW 0x00000008 /* only 460EX/GT */
+#define DCRN_L2C0_CMD 0x01
+#define L2C_CMD_CLR 0x80000000
+#define L2C_CMD_DIAG 0x40000000
+#define L2C_CMD_INV 0x20000000
+#define L2C_CMD_CCP 0x10000000
+#define L2C_CMD_CTE 0x08000000
+#define L2C_CMD_STRC 0x04000000
+#define L2C_CMD_STPC 0x02000000
+#define L2C_CMD_RPMC 0x01000000
+#define L2C_CMD_HCC 0x00800000
+#define DCRN_L2C0_ADDR 0x02
+#define DCRN_L2C0_DATA 0x03
+#define DCRN_L2C0_SR 0x04
+#define L2C_SR_CC 0x80000000
+#define L2C_SR_CPE 0x40000000
+#define L2C_SR_TPE 0x20000000
+#define L2C_SR_LRU 0x10000000
+#define L2C_SR_PCS 0x08000000
+#define DCRN_L2C0_REVID 0x05
+#define DCRN_L2C0_SNP0 0x06
+#define DCRN_L2C0_SNP1 0x07
+#define L2C_SNP_BA_MASK 0xffff0000
+#define L2C_SNP_SSR_MASK 0x0000f000
+#define L2C_SNP_SSR_32G 0x0000f000
+#define L2C_SNP_ESR 0x00000800
+
#endif /* __DCR_REGS_H__ */

--
1.5.4.4