TX39/TX49 can enable/disable I/D cache at runtime. Add kernel options
to control them. This is useful to debug some cache-related issues,
such as aliasing or I/D coherency. Also enable CWF bit for TX49 SoCs.
Signed-off-by: Atsushi Nemoto <anemo@xxxxxxxxxxxxx>
---
arch/mips/txx9/generic/setup.c | 113 +++++++++++++++++++++++++++++++++
arch/mips/txx9/generic/setup_tx3927.c | 18 +++---
arch/mips/txx9/generic/setup_tx4927.c | 1 +
arch/mips/txx9/generic/setup_tx4938.c | 1 +
arch/mips/txx9/jmr3927/setup.c | 11 +---
arch/mips/txx9/rbtx4927/setup.c | 6 --
6 files changed, 124 insertions(+), 26 deletions(-)
diff --git a/arch/mips/txx9/generic/setup.c b/arch/mips/txx9/generic/setup.c
index af97514..48aba94 100644
--- a/arch/mips/txx9/generic/setup.c
+++ b/arch/mips/txx9/generic/setup.c
@@ -25,6 +25,7 @@
#include <asm/bootinfo.h>
#include <asm/time.h>
#include <asm/reboot.h>
+#include <asm/r4kcache.h>
#include <asm/txx9/generic.h>
#include <asm/txx9/pci.h>
#ifdef CONFIG_CPU_TX49XX
@@ -185,6 +186,110 @@ static void __init prom_init_cmdline(void)
}
}
+static int txx9_ic_disable __initdata;
+static int txx9_dc_disable __initdata;
+
+#if defined(CONFIG_CPU_TX49XX)
+/* flush all cache on very early stage (before 4k_cache_init) */
+static void __init early_flush_dcache(void)
+{
+ unsigned int conf = read_c0_config();
+ unsigned int dc_size = 1 << (12 + ((conf & CONF_DC) >> 6));
+ unsigned int linesz = 32;
+ unsigned long addr, end;
+
+ end = INDEX_BASE + dc_size / 4;
+ /* 4way, waybit=0 */
+ for (addr = INDEX_BASE; addr < end; addr += linesz) {
+ cache_op(Index_Writeback_Inv_D, addr | 0);
+ cache_op(Index_Writeback_Inv_D, addr | 1);
+ cache_op(Index_Writeback_Inv_D, addr | 2);
+ cache_op(Index_Writeback_Inv_D, addr | 3);
+ }
+}
+
+static void __init txx9_cache_fixup(void)
+{
+ unsigned int conf;
+
+ conf = read_c0_config();
+ /* flush and disable */
+ if (txx9_ic_disable) {
+ conf |= TX49_CONF_IC;
+ write_c0_config(conf);
+ }
+ if (txx9_dc_disable) {
+ early_flush_dcache();
+ conf |= TX49_CONF_DC;
+ write_c0_config(conf);
+ }
+
+ /* enable cache */
+ conf = read_c0_config();
+ if (!txx9_ic_disable)
+ conf &= ~TX49_CONF_IC;
+ if (!txx9_dc_disable)
+ conf &= ~TX49_CONF_DC;
+ write_c0_config(conf);
+
+ if (conf & TX49_CONF_IC)
+ pr_info("TX49XX I-Cache disabled.\n");
+ if (conf & TX49_CONF_DC)
+ pr_info("TX49XX D-Cache disabled.\n");
+}
+#elif defined(CONFIG_CPU_TX39XX)
+/* flush all cache on very early stage (before tx39_cache_init) */
+static void __init early_flush_dcache(void)
+{
+ unsigned int conf = read_c0_config();
+ unsigned int dc_size = 1 << (10 + ((conf & TX39_CONF_DCS_MASK) >>
+ TX39_CONF_DCS_SHIFT));
+ unsigned int linesz = 16;
+ unsigned long addr, end;
+
+ end = INDEX_BASE + dc_size / 2;
+ /* 2way, waybit=0 */
+ for (addr = INDEX_BASE; addr < end; addr += linesz) {
+ cache_op(Index_Writeback_Inv_D, addr | 0);
+ cache_op(Index_Writeback_Inv_D, addr | 1);
+ }
+}
+
+static void __init txx9_cache_fixup(void)
+{
+ unsigned int conf;
+
+ conf = read_c0_config();
+ /* flush and disable */
+ if (txx9_ic_disable) {
+ conf &= ~TX39_CONF_ICE;
+ write_c0_config(conf);
+ }
+ if (txx9_dc_disable) {
+ early_flush_dcache();
+ conf &= ~TX39_CONF_DCE;
+ write_c0_config(conf);
+ }
+
+ /* enable cache */
+ conf = read_c0_config();
+ if (!txx9_ic_disable)
+ conf |= TX39_CONF_ICE;
+ if (!txx9_dc_disable)
+ conf |= TX39_CONF_DCE;
+ write_c0_config(conf);
+
+ if (!(conf & TX39_CONF_ICE))
+ pr_info("TX39XX I-Cache disabled.\n");
+ if (!(conf & TX39_CONF_DCE))
+ pr_info("TX39XX D-Cache disabled.\n");
+}
+#else
+static inline void txx9_cache_fixup(void)
+{
+}
+#endif
+
static void __init preprocess_cmdline(void)
{
char cmdline[CL_SIZE];
@@ -203,11 +308,19 @@ static void __init preprocess_cmdline(void)
if (strict_strtoul(str + 10, 10, &val) == 0)
txx9_master_clock = val;
continue;
+ } else if (strcmp(str, "icdisable") == 0) {
+ txx9_ic_disable = 1;
+ continue;
+ } else if (strcmp(str, "dcdisable") == 0) {
+ txx9_dc_disable = 1;
+ continue;
}
if (arcs_cmdline[0])
strcat(arcs_cmdline, " ");
strcat(arcs_cmdline, str);
}
+
+ txx9_cache_fixup();
}
static void __init select_board(void)
diff --git a/arch/mips/txx9/generic/setup_tx3927.c b/arch/mips/txx9/generic/setup_tx3927.c
index 7bd963d..4bc2f85 100644
--- a/arch/mips/txx9/generic/setup_tx3927.c
+++ b/arch/mips/txx9/generic/setup_tx3927.c
@@ -99,16 +99,14 @@ void __init tx3927_setup(void)
txx9_gpio_init(TX3927_PIO_REG, 0, 16);
conf = read_c0_conf();
- if (!(conf & TX39_CONF_ICE))
- printk(KERN_INFO "TX3927 I-Cache disabled.\n");
- if (!(conf & TX39_CONF_DCE))
- printk(KERN_INFO "TX3927 D-Cache disabled.\n");
- else if (!(conf & TX39_CONF_WBON))
- printk(KERN_INFO "TX3927 D-Cache WriteThrough.\n");
- else if (!(conf & TX39_CONF_CWFON))
- printk(KERN_INFO "TX3927 D-Cache WriteBack.\n");
- else
- printk(KERN_INFO "TX3927 D-Cache WriteBack (CWF) .\n");
+ if (conf & TX39_CONF_DCE) {
+ if (!(conf & TX39_CONF_WBON))
+ pr_info("TX3927 D-Cache WriteThrough.\n");
+ else if (!(conf & TX39_CONF_CWFON))
+ pr_info("TX3927 D-Cache WriteBack.\n");
+ else
+ pr_info("TX3927 D-Cache WriteBack (CWF) .\n");
+ }
}
void __init tx3927_time_init(unsigned int evt_tmrnr, unsigned int src_tmrnr)
diff --git a/arch/mips/txx9/generic/setup_tx4927.c b/arch/mips/txx9/generic/setup_tx4927.c
index f80d4b7..e679c79 100644
--- a/arch/mips/txx9/generic/setup_tx4927.c
+++ b/arch/mips/txx9/generic/setup_tx4927.c
@@ -44,6 +44,7 @@ void __init tx4927_setup(void)
txx9_reg_res_init(TX4927_REV_PCODE(), TX4927_REG_BASE,
TX4927_REG_SIZE);
+ set_c0_config(TX49_CONF_CWFON);
/* SDRAMC,EBUSC are configured by PROM */
for (i = 0; i < 8; i++) {
diff --git a/arch/mips/txx9/generic/setup_tx4938.c b/arch/mips/txx9/generic/setup_tx4938.c
index f3040b9..95c058f 100644
--- a/arch/mips/txx9/generic/setup_tx4938.c
+++ b/arch/mips/txx9/generic/setup_tx4938.c
@@ -47,6 +47,7 @@ void __init tx4938_setup(void)
txx9_reg_res_init(TX4938_REV_PCODE(), TX4938_REG_BASE,
TX4938_REG_SIZE);
+ set_c0_config(TX49_CONF_CWFON);
/* SDRAMC,EBUSC are configured by PROM */
for (i = 0; i < 8; i++) {
diff --git a/arch/mips/txx9/jmr3927/setup.c b/arch/mips/txx9/jmr3927/setup.c
index 87db41b..2e40a92 100644
--- a/arch/mips/txx9/jmr3927/setup.c
+++ b/arch/mips/txx9/jmr3927/setup.c
@@ -62,7 +62,6 @@ static void __init jmr3927_time_init(void)
}
#define DO_WRITE_THROUGH
-#define DO_ENABLE_CACHE
static void jmr3927_board_init(void);
@@ -77,11 +76,6 @@ static void __init jmr3927_mem_setup(void)
/* cache setup */
{
unsigned int conf;
-#ifdef DO_ENABLE_CACHE
- int mips_ic_disable = 0, mips_dc_disable = 0;
-#else
- int mips_ic_disable = 1, mips_dc_disable = 1;
-#endif
#ifdef DO_WRITE_THROUGH
int mips_config_cwfon = 0;
int mips_config_wbon = 0;
@@ -91,10 +85,7 @@ static void __init jmr3927_mem_setup(void)
#endif
conf = read_c0_conf();
- conf &= ~(TX39_CONF_ICE | TX39_CONF_DCE |
- TX39_CONF_WBON | TX39_CONF_CWFON);
- conf |= mips_ic_disable ? 0 : TX39_CONF_ICE;
- conf |= mips_dc_disable ? 0 : TX39_CONF_DCE;
+ conf &= ~(TX39_CONF_WBON | TX39_CONF_CWFON);
conf |= mips_config_wbon ? TX39_CONF_WBON : 0;
conf |= mips_config_cwfon ? TX39_CONF_CWFON : 0;
diff --git a/arch/mips/txx9/rbtx4927/setup.c b/arch/mips/txx9/rbtx4927/setup.c
index 5985f33..0464a39 100644
--- a/arch/mips/txx9/rbtx4927/setup.c
+++ b/arch/mips/txx9/rbtx4927/setup.c
@@ -186,14 +186,8 @@ static void __init rbtx4937_clock_init(void);
static void __init rbtx4927_mem_setup(void)
{
- u32 cp0_config;
char *argptr;
- /* enable caches -- HCP5 does this, pmon does not */
- cp0_config = read_c0_config();
- cp0_config = cp0_config & ~(TX49_CONF_IC | TX49_CONF_DC);
- write_c0_config(cp0_config);
-
if (TX4927_REV_PCODE() == 0x4927) {
rbtx4927_clock_init();
tx4927_setup();
--
1.5.6.3
