diff options
Diffstat (limited to 'arch/mips/mm/sc-mips.c')
-rw-r--r-- | arch/mips/mm/sc-mips.c | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/arch/mips/mm/sc-mips.c b/arch/mips/mm/sc-mips.c new file mode 100644 index 0000000..d3f92a9 --- /dev/null +++ b/arch/mips/mm/sc-mips.c @@ -0,0 +1,141 @@ +/* + * Copyright (C) 2006 Chris Dearman (chris@mips.com), + */ +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/mm.h> + +#include <asm/mipsregs.h> +#include <asm/bcache.h> +#include <asm/cacheops.h> +#include <asm/page.h> +#include <asm/pgtable.h> +#include <asm/system.h> +#include <asm/mmu_context.h> +#include <asm/r4kcache.h> + +/* + * MIPS32/MIPS64 L2 cache handling + */ + +/* + * Writeback and invalidate the secondary cache before DMA. + */ +static void mips_sc_wback_inv(unsigned long addr, unsigned long size) +{ + unsigned long sc_lsize = cpu_scache_line_size(); + unsigned long end, a; + + pr_debug("mips_sc_wback_inv[%08lx,%08lx]", addr, size); + + /* Catch bad driver code */ + BUG_ON(size == 0); + + a = addr & ~(sc_lsize - 1); + end = (addr + size - 1) & ~(sc_lsize - 1); + while (1) { + flush_scache_line(a); /* Hit_Writeback_Inv_SD */ + if (a == end) + break; + a += sc_lsize; + } +} + +/* + * Invalidate the secondary cache before DMA. + */ +static void mips_sc_inv(unsigned long addr, unsigned long size) +{ + unsigned long sc_lsize = cpu_scache_line_size(); + unsigned long end, a; + + pr_debug("mips_sc_inv[%08lx,%08lx]", addr, size); + + /* Catch bad driver code */ + BUG_ON(size == 0); + + a = addr & ~(sc_lsize - 1); + end = (addr + size - 1) & ~(sc_lsize - 1); + while (1) { + invalidate_scache_line(a); /* Hit_Invalidate_SD */ + if (a == end) + break; + a += sc_lsize; + } +} + +static void mips_sc_enable(void) +{ + /* L2 cache is permanently enabled */ +} + +static void mips_sc_disable(void) +{ + /* L2 cache is permanently enabled */ +} + +static struct bcache_ops mips_sc_ops = { + .bc_enable = mips_sc_enable, + .bc_disable = mips_sc_disable, + .bc_wback_inv = mips_sc_wback_inv, + .bc_inv = mips_sc_inv +}; + +static inline int __init mips_sc_probe(void) +{ + struct cpuinfo_mips *c = ¤t_cpu_data; + unsigned int config1, config2; + unsigned int tmp; + + /* Mark as not present until probe completed */ + c->scache.flags |= MIPS_CACHE_NOT_PRESENT; + + /* Ignore anything but MIPSxx processors */ + if (c->isa_level != MIPS_CPU_ISA_M32R1 && + c->isa_level != MIPS_CPU_ISA_M32R2 && + c->isa_level != MIPS_CPU_ISA_M64R1 && + c->isa_level != MIPS_CPU_ISA_M64R2) + return 0; + + /* Does this MIPS32/MIPS64 CPU have a config2 register? */ + config1 = read_c0_config1(); + if (!(config1 & MIPS_CONF_M)) + return 0; + + config2 = read_c0_config2(); + tmp = (config2 >> 4) & 0x0f; + if (0 < tmp && tmp <= 7) + c->scache.linesz = 2 << tmp; + else + return 0; + + tmp = (config2 >> 8) & 0x0f; + if (0 <= tmp && tmp <= 7) + c->scache.sets = 64 << tmp; + else + return 0; + + tmp = (config2 >> 0) & 0x0f; + if (0 <= tmp && tmp <= 7) + c->scache.ways = tmp + 1; + else + return 0; + + c->scache.waysize = c->scache.sets * c->scache.linesz; + + c->scache.flags &= ~MIPS_CACHE_NOT_PRESENT; + + return 1; +} + +int __init mips_sc_init(void) +{ + int found = mips_sc_probe (); + if (found) { + mips_sc_enable(); + bcops = &mips_sc_ops; + } + return found; +} + |