diff options
Diffstat (limited to 'arch/arm/mm')
| -rw-r--r-- | arch/arm/mm/Kconfig | 9 | ||||
| -rw-r--r-- | arch/arm/mm/Makefile | 2 | ||||
| -rw-r--r-- | arch/arm/mm/cache-tauros2.c | 263 |
3 files changed, 273 insertions, 1 deletions
diff --git a/arch/arm/mm/Kconfig b/arch/arm/mm/Kconfig index 1549863d7b5..4958ef2c625 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 055cb2aa813..06bcf2e7385 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 00000000000..50868651890 --- /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); +} |