diff options
Diffstat (limited to 'arch/mips/mm/sc-r5k.c')
-rw-r--r-- | arch/mips/mm/sc-r5k.c | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/arch/mips/mm/sc-r5k.c b/arch/mips/mm/sc-r5k.c new file mode 100644 index 000000000..736615d68 --- /dev/null +++ b/arch/mips/mm/sc-r5k.c @@ -0,0 +1,107 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 1997, 2001 Ralf Baechle (ralf@gnu.org), + * derived from r4xx0.c by David S. Miller (davem@davemloft.net). + */ +#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/mmu_context.h> +#include <asm/r4kcache.h> + +/* Secondary cache size in bytes, if present. */ +static unsigned long scache_size; + +#define SC_LINE 32 +#define SC_PAGE (128*SC_LINE) + +static inline void blast_r5000_scache(void) +{ + unsigned long start = INDEX_BASE; + unsigned long end = start + scache_size; + + while(start < end) { + cache_op(R5K_Page_Invalidate_S, start); + start += SC_PAGE; + } +} + +static void r5k_dma_cache_inv_sc(unsigned long addr, unsigned long size) +{ + unsigned long end, a; + + /* Catch bad driver code */ + BUG_ON(size == 0); + + if (size >= scache_size) { + blast_r5000_scache(); + return; + } + + /* On the R5000 secondary cache we cannot + * invalidate less than a page at a time. + * The secondary cache is physically indexed, write-through. + */ + a = addr & ~(SC_PAGE - 1); + end = (addr + size - 1) & ~(SC_PAGE - 1); + while (a <= end) { + cache_op(R5K_Page_Invalidate_S, a); + a += SC_PAGE; + } +} + +static void r5k_sc_enable(void) +{ + unsigned long flags; + + local_irq_save(flags); + set_c0_config(R5K_CONF_SE); + blast_r5000_scache(); + local_irq_restore(flags); +} + +static void r5k_sc_disable(void) +{ + unsigned long flags; + + local_irq_save(flags); + blast_r5000_scache(); + clear_c0_config(R5K_CONF_SE); + local_irq_restore(flags); +} + +static inline int __init r5k_sc_probe(void) +{ + unsigned long config = read_c0_config(); + + if (config & CONF_SC) + return 0; + + scache_size = (512 * 1024) << ((config & R5K_CONF_SS) >> 20); + + printk("R5000 SCACHE size %ldkB, linesize 32 bytes.\n", + scache_size >> 10); + + return 1; +} + +static struct bcache_ops r5k_sc_ops = { + .bc_enable = r5k_sc_enable, + .bc_disable = r5k_sc_disable, + .bc_wback_inv = r5k_dma_cache_inv_sc, + .bc_inv = r5k_dma_cache_inv_sc +}; + +void r5k_sc_init(void) +{ + if (r5k_sc_probe()) { + r5k_sc_enable(); + bcops = &r5k_sc_ops; + } +} |