[PATCH 2/3] Add Tauros2 L2 cache controller support
Saeed Bishara
saeed at marvell.com
Tue Nov 24 12:33:52 EST 2009
From: Lennert Buytenhek <buytenh at marvell.com>
Support for the Tauros2 L2 cache controller as used with the PJ1
and PJ4 CPUs.
Signed-off-by: Lennert Buytenhek <buytenh at marvell.com>
Signed-off-by: Saeed Bishara <saeed at marvell.com>
---
arch/arm/configs/dove_defconfig | 4 +-
arch/arm/include/asm/hardware/cache-tauros2.h | 11 +
arch/arm/mach-dove/common.c | 4 +
arch/arm/mm/Kconfig | 9 +
arch/arm/mm/Makefile | 2 +-
arch/arm/mm/cache-tauros2.c | 263 +++++++++++++++++++++++++
6 files changed, 291 insertions(+), 2 deletions(-)
create mode 100644 arch/arm/include/asm/hardware/cache-tauros2.h
create mode 100644 arch/arm/mm/cache-tauros2.c
diff --git a/arch/arm/configs/dove_defconfig b/arch/arm/configs/dove_defconfig
index f2d1ea0..837bb52 100644
--- a/arch/arm/configs/dove_defconfig
+++ b/arch/arm/configs/dove_defconfig
@@ -1,7 +1,7 @@
#
# Automatically generated make config: don't edit
# Linux kernel version: 2.6.32-rc6
-# Tue Nov 24 13:48:39 2009
+# Tue Nov 24 13:51:23 2009
#
CONFIG_ARM=y
CONFIG_SYS_SUPPORTS_APM_EMULATION=y
@@ -207,6 +207,8 @@ CONFIG_ARM_THUMB=y
# CONFIG_CPU_ICACHE_DISABLE is not set
# CONFIG_CPU_DCACHE_DISABLE is not set
# CONFIG_CPU_BPREDICT_DISABLE is not set
+CONFIG_OUTER_CACHE=y
+CONFIG_CACHE_TAUROS2=y
CONFIG_ARM_L1_CACHE_SHIFT=5
# CONFIG_ARM_ERRATA_411920 is not set
diff --git a/arch/arm/include/asm/hardware/cache-tauros2.h b/arch/arm/include/asm/hardware/cache-tauros2.h
new file mode 100644
index 0000000..dacfde9
--- /dev/null
+++ b/arch/arm/include/asm/hardware/cache-tauros2.h
@@ -0,0 +1,11 @@
+/*
+ * arch/arm/plat-orion/include/plat/cache-tauros2.h
+ *
+ * Copyright (C) 2008 Marvell Semiconductor
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+extern void __init tauros2_init(void);
diff --git a/arch/arm/mach-dove/common.c b/arch/arm/mach-dove/common.c
index a9248ce..bf66b13 100644
--- a/arch/arm/mach-dove/common.c
+++ b/arch/arm/mach-dove/common.c
@@ -20,6 +20,7 @@
#include <linux/mv643xx_i2c.h>
#include <linux/ata_platform.h>
#include <linux/spi/orion_spi.h>
+#include <asm/hardware/cache-tauros2.h>
#include <asm/page.h>
#include <asm/setup.h>
#include <asm/timex.h>
@@ -760,6 +761,9 @@ void __init dove_init(void)
printk(KERN_INFO "Dove 88AP510 SoC, ");
printk(KERN_INFO "TCLK = %dMHz\n", (tclk + 499999) / 1000000);
+#ifdef CONFIG_CACHE_TAUROS2
+ tauros2_init();
+#endif
dove_setup_cpu_mbus();
dove_ge00_shared_data.t_clk = tclk;
diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig
index 1549863..4958ef2 100644
--- a/arch/arm/mm/Kconfig
+++ b/arch/arm/mm/Kconfig
@@ -764,6 +764,15 @@ config CACHE_L2X0
help
This option enables the L2x0 PrimeCell.
+config CACHE_TAUROS2
+ bool "Enable the Tauros2 L2 cache controller"
+ depends on ARCH_DOVE
+ default y
+ select OUTER_CACHE
+ help
+ This option enables the Tauros2 L2 cache controller (as
+ found on PJ1/PJ4).
+
config CACHE_XSC3L2
bool "Enable the L2 cache on XScale3"
depends on CPU_XSC3
diff --git a/arch/arm/mm/Makefile b/arch/arm/mm/Makefile
index 055cb2a..06bcf2e 100644
--- a/arch/arm/mm/Makefile
+++ b/arch/arm/mm/Makefile
@@ -87,4 +87,4 @@ obj-$(CONFIG_CPU_V7) += proc-v7.o
obj-$(CONFIG_CACHE_FEROCEON_L2) += cache-feroceon-l2.o
obj-$(CONFIG_CACHE_L2X0) += cache-l2x0.o
obj-$(CONFIG_CACHE_XSC3L2) += cache-xsc3l2.o
-
+obj-$(CONFIG_CACHE_TAUROS2) += cache-tauros2.o
diff --git a/arch/arm/mm/cache-tauros2.c b/arch/arm/mm/cache-tauros2.c
new file mode 100644
index 0000000..5086865
--- /dev/null
+++ b/arch/arm/mm/cache-tauros2.c
@@ -0,0 +1,263 @@
+/*
+ * arch/arm/mm/cache-tauros2.c - Tauros2 L2 cache controller support
+ *
+ * Copyright (C) 2008 Marvell Semiconductor
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ *
+ * References:
+ * - PJ1 CPU Core Datasheet,
+ * Document ID MV-S104837-01, Rev 0.7, January 24 2008.
+ * - PJ4 CPU Core Datasheet,
+ * Document ID MV-S105190-00, Rev 0.7, March 14 2008.
+ */
+
+#include <linux/init.h>
+#include <asm/cacheflush.h>
+#include <asm/hardware/cache-tauros2.h>
+
+
+/*
+ * When Tauros2 is used on a CPU that supports the v7 hierarchical
+ * cache operations, the cache handling code in proc-v7.S takes care
+ * of everything, including handling DMA coherency.
+ *
+ * So, we only need to register outer cache operations here if we're
+ * being used on a pre-v7 CPU, and we only need to build support for
+ * outer cache operations into the kernel image if the kernel has been
+ * configured to support a pre-v7 CPU.
+ */
+#if __LINUX_ARM_ARCH__ < 7
+/*
+ * Low-level cache maintenance operations.
+ */
+static inline void tauros2_clean_pa(unsigned long addr)
+{
+ __asm__("mcr p15, 1, %0, c7, c11, 3" : : "r" (addr));
+}
+
+static inline void tauros2_clean_inv_pa(unsigned long addr)
+{
+ __asm__("mcr p15, 1, %0, c7, c15, 3" : : "r" (addr));
+}
+
+static inline void tauros2_inv_pa(unsigned long addr)
+{
+ __asm__("mcr p15, 1, %0, c7, c7, 3" : : "r" (addr));
+}
+
+
+/*
+ * Linux primitives.
+ *
+ * Note that the end addresses passed to Linux primitives are
+ * noninclusive.
+ */
+#define CACHE_LINE_SIZE 32
+
+static void tauros2_inv_range(unsigned long start, unsigned long end)
+{
+ /*
+ * Clean and invalidate partial first cache line.
+ */
+ if (start & (CACHE_LINE_SIZE - 1)) {
+ tauros2_clean_inv_pa(start & ~(CACHE_LINE_SIZE - 1));
+ start = (start | (CACHE_LINE_SIZE - 1)) + 1;
+ }
+
+ /*
+ * Clean and invalidate partial last cache line.
+ */
+ if (end & (CACHE_LINE_SIZE - 1)) {
+ tauros2_clean_inv_pa(end & ~(CACHE_LINE_SIZE - 1));
+ end &= ~(CACHE_LINE_SIZE - 1);
+ }
+
+ /*
+ * Invalidate all full cache lines between 'start' and 'end'.
+ */
+ while (start < end) {
+ tauros2_inv_pa(start);
+ start += CACHE_LINE_SIZE;
+ }
+
+ dsb();
+}
+
+static void tauros2_clean_range(unsigned long start, unsigned long end)
+{
+ start &= ~(CACHE_LINE_SIZE - 1);
+ while (start < end) {
+ tauros2_clean_pa(start);
+ start += CACHE_LINE_SIZE;
+ }
+
+ dsb();
+}
+
+static void tauros2_flush_range(unsigned long start, unsigned long end)
+{
+ start &= ~(CACHE_LINE_SIZE - 1);
+ while (start < end) {
+ tauros2_clean_inv_pa(start);
+ start += CACHE_LINE_SIZE;
+ }
+
+ dsb();
+}
+#endif
+
+static inline u32 __init read_extra_features(void)
+{
+ u32 u;
+
+ __asm__("mrc p15, 1, %0, c15, c1, 0" : "=r" (u));
+
+ return u;
+}
+
+static inline void __init write_extra_features(u32 u)
+{
+ __asm__("mcr p15, 1, %0, c15, c1, 0" : : "r" (u));
+}
+
+static void __init disable_l2_prefetch(void)
+{
+ u32 u;
+
+ /*
+ * Read the CPU Extra Features register and verify that the
+ * Disable L2 Prefetch bit is set.
+ */
+ u = read_extra_features();
+ if (!(u & 0x01000000)) {
+ printk(KERN_INFO "Tauros2: Disabling L2 prefetch.\n");
+ write_extra_features(u | 0x01000000);
+ }
+}
+
+static inline int __init cpuid_scheme(void)
+{
+ extern int processor_id;
+
+ return !!((processor_id & 0x000f0000) == 0x000f0000);
+}
+
+static inline u32 __init read_mmfr3(void)
+{
+ u32 mmfr3;
+
+ __asm__("mrc p15, 0, %0, c0, c1, 7\n" : "=r" (mmfr3));
+
+ return mmfr3;
+}
+
+static inline u32 __init read_actlr(void)
+{
+ u32 actlr;
+
+ __asm__("mrc p15, 0, %0, c1, c0, 1\n" : "=r" (actlr));
+
+ return actlr;
+}
+
+static inline void __init write_actlr(u32 actlr)
+{
+ __asm__("mcr p15, 0, %0, c1, c0, 1\n" : : "r" (actlr));
+}
+
+void __init tauros2_init(void)
+{
+ extern int processor_id;
+ char *mode;
+
+ disable_l2_prefetch();
+
+#ifdef CONFIG_CPU_32v5
+ if ((processor_id & 0xff0f0000) == 0x56050000) {
+ u32 feat;
+
+ /*
+ * v5 CPUs with Tauros2 have the L2 cache enable bit
+ * located in the CPU Extra Features register.
+ */
+ feat = read_extra_features();
+ if (!(feat & 0x00400000)) {
+ printk(KERN_INFO "Tauros2: Enabling L2 cache.\n");
+ write_extra_features(feat | 0x00400000);
+ }
+
+ mode = "ARMv5";
+ outer_cache.inv_range = tauros2_inv_range;
+ outer_cache.clean_range = tauros2_clean_range;
+ outer_cache.flush_range = tauros2_flush_range;
+ }
+#endif
+
+#ifdef CONFIG_CPU_32v6
+ /*
+ * Check whether this CPU lacks support for the v7 hierarchical
+ * cache ops. (PJ4 is in its v6 personality mode if the MMFR3
+ * register indicates no support for the v7 hierarchical cache
+ * ops.)
+ */
+ if (cpuid_scheme() && (read_mmfr3() & 0xf) == 0) {
+ /*
+ * When Tauros2 is used in an ARMv6 system, the L2
+ * enable bit is in the ARMv6 ARM-mandated position
+ * (bit [26] of the System Control Register).
+ */
+ if (!(get_cr() & 0x04000000)) {
+ printk(KERN_INFO "Tauros2: Enabling L2 cache.\n");
+ adjust_cr(0x04000000, 0x04000000);
+ }
+
+ mode = "ARMv6";
+ outer_cache.inv_range = tauros2_inv_range;
+ outer_cache.clean_range = tauros2_clean_range;
+ outer_cache.flush_range = tauros2_flush_range;
+ }
+#endif
+
+#ifdef CONFIG_CPU_32v7
+ /*
+ * Check whether this CPU has support for the v7 hierarchical
+ * cache ops. (PJ4 is in its v7 personality mode if the MMFR3
+ * register indicates support for the v7 hierarchical cache
+ * ops.)
+ *
+ * (Although strictly speaking there may exist CPUs that
+ * implement the v7 cache ops but are only ARMv6 CPUs (due to
+ * not complying with all of the other ARMv7 requirements),
+ * there are no real-life examples of Tauros2 being used on
+ * such CPUs as of yet.)
+ */
+ if (cpuid_scheme() && (read_mmfr3() & 0xf) == 1) {
+ u32 actlr;
+
+ /*
+ * When Tauros2 is used in an ARMv7 system, the L2
+ * enable bit is located in the Auxiliary System Control
+ * Register (which is the only register allowed by the
+ * ARMv7 spec to contain fine-grained cache control bits).
+ */
+ actlr = read_actlr();
+ if (!(actlr & 0x00000002)) {
+ printk(KERN_INFO "Tauros2: Enabling L2 cache.\n");
+ write_actlr(actlr | 0x00000002);
+ }
+
+ mode = "ARMv7";
+ }
+#endif
+
+ if (mode == NULL) {
+ printk(KERN_CRIT "Tauros2: Unable to detect CPU mode.\n");
+ return;
+ }
+
+ printk(KERN_INFO "Tauros2: L2 cache support initialised "
+ "in %s mode.\n", mode);
+}
--
1.6.0.4
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