[MIPS] Sibyte: Replace SB1 cachecode with standard R4000 class cache code.

It may not be perfect yet but the SB1 code is badly borken and has
horrible performance issues.

Downside: This seriously breaks support for pass 1 parts of the BCM1250
where indexed cacheops don't work quite reliable but I seem to be the
last one on the planet with a pass 1 part anyway.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

5 files changed, 29 insertions, 547 deletions

diff --git a/arch/mips/mm/Makefile b/arch/mips/mm/Makefile
index 43e4810dcaa8..32fd5db95774 100644
--- a/arch/mips/mm/Makefile
+++ b/arch/mips/mm/Makefile
@@ -22,7 +22,7 @@ obj-$(CONFIG_CPU_R5432)		+= c-r4k.o cex-gen.o pg-r4k.o tlb-r4k.o
 obj-$(CONFIG_CPU_R8000)		+= c-r4k.o cex-gen.o pg-r4k.o tlb-r8k.o
 obj-$(CONFIG_CPU_RM7000)	+= c-r4k.o cex-gen.o pg-r4k.o tlb-r4k.o
 obj-$(CONFIG_CPU_RM9000)	+= c-r4k.o cex-gen.o pg-r4k.o tlb-r4k.o
-obj-$(CONFIG_CPU_SB1)		+= c-sb1.o cerr-sb1.o cex-sb1.o pg-sb1.o \
+obj-$(CONFIG_CPU_SB1)		+= c-r4k.o cerr-sb1.o cex-sb1.o pg-sb1.o \
 				   tlb-r4k.o
 obj-$(CONFIG_CPU_TX39XX)	+= c-tx39.o pg-r4k.o tlb-r3k.o
 obj-$(CONFIG_CPU_TX49XX)	+= c-r4k.o cex-gen.o pg-r4k.o tlb-r4k.o
diff --git a/arch/mips/mm/c-r4k.c b/arch/mips/mm/c-r4k.c
index bad571971bf6..738b89803a44 100644
--- a/arch/mips/mm/c-r4k.c
+++ b/arch/mips/mm/c-r4k.c
@@ -9,6 +9,7 @@
  */
 #include <linux/init.h>
 #include <linux/kernel.h>
+#include <linux/linkage.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
 #include <linux/bitops.h>
@@ -948,12 +949,16 @@ static void __init probe_pcache(void)
 	switch (c->cputype) {
 	case CPU_20KC:
 	case CPU_25KF:
+	case CPU_SB1:
+	case CPU_SB1A:
 		c->dcache.flags |= MIPS_CACHE_PINDEX;
+		break;
+
 	case CPU_R10000:
 	case CPU_R12000:
 	case CPU_R14000:
-	case CPU_SB1:
 		break;
+
 	case CPU_24K:
 	case CPU_34K:
 	case CPU_74K:
@@ -1235,11 +1240,20 @@ void __init r4k_cache_init(void)
 {
 	extern void build_clear_page(void);
 	extern void build_copy_page(void);
-	extern char except_vec2_generic;
+	extern char __weak except_vec2_generic;
+	extern char __weak except_vec2_sb1;
 	struct cpuinfo_mips *c = &current_cpu_data;
 
-	/* Default cache error handler for R4000 and R5000 family */
-	set_uncached_handler (0x100, &except_vec2_generic, 0x80);
+	switch (c->cputype) {
+	case CPU_SB1:
+	case CPU_SB1A:
+		set_uncached_handler(0x100, &except_vec2_sb1, 0x80);
+		break;
+
+	default:
+		set_uncached_handler(0x100, &except_vec2_generic, 0x80);
+		break;
+	}
 
 	probe_pcache();
 	setup_scache();
diff --git a/arch/mips/mm/c-sb1.c b/arch/mips/mm/c-sb1.c
deleted file mode 100644
index 85ce2842d0da..000000000000
--- a/arch/mips/mm/c-sb1.c
+++ /dev/null
@@ -1,535 +0,0 @@
-/*
- * Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
- * Copyright (C) 1997, 2001 Ralf Baechle (ralf@gnu.org)
- * Copyright (C) 2000, 2001, 2002, 2003 Broadcom Corporation
- * Copyright (C) 2004  Maciej W. Rozycki
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of the GNU General Public License
- * as published by the Free Software Foundation; either version 2
- * of the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
- */
-#include <linux/init.h>
-#include <linux/hardirq.h>
-
-#include <asm/asm.h>
-#include <asm/bootinfo.h>
-#include <asm/cacheops.h>
-#include <asm/cpu.h>
-#include <asm/mipsregs.h>
-#include <asm/mmu_context.h>
-#include <asm/uaccess.h>
-
-extern void sb1_dma_init(void);
-
-/* These are probed at ld_mmu time */
-static unsigned long icache_size;
-static unsigned long dcache_size;
-
-static unsigned short icache_line_size;
-static unsigned short dcache_line_size;
-
-static unsigned int icache_index_mask;
-static unsigned int dcache_index_mask;
-
-static unsigned short icache_assoc;
-static unsigned short dcache_assoc;
-
-static unsigned short icache_sets;
-static unsigned short dcache_sets;
-
-static unsigned int icache_range_cutoff;
-static unsigned int dcache_range_cutoff;
-
-static inline void sb1_on_each_cpu(void (*func) (void *info), void *info,
-				   int retry, int wait)
-{
-	preempt_disable();
-	smp_call_function(func, info, retry, wait);
-	func(info);
-	preempt_enable();
-}
-
-/*
- * The dcache is fully coherent to the system, with one
- * big caveat:  the instruction stream.  In other words,
- * if we miss in the icache, and have dirty data in the
- * L1 dcache, then we'll go out to memory (or the L2) and
- * get the not-as-recent data.
- *
- * So the only time we have to flush the dcache is when
- * we're flushing the icache.  Since the L2 is fully
- * coherent to everything, including I/O, we never have
- * to flush it
- */
-
-#define cache_set_op(op, addr)						\
-	__asm__ __volatile__(						\
-	"	.set	noreorder		\n"			\
-	"	.set	mips64\n\t		\n"			\
-	"	cache	%0, (0<<13)(%1)		\n"			\
-	"	cache	%0, (1<<13)(%1)		\n"			\
-	"	cache	%0, (2<<13)(%1)		\n"			\
-	"	cache	%0, (3<<13)(%1)		\n"			\
-	"	.set	mips0			\n"			\
-	"	.set	reorder"					\
-	:								\
-	: "i" (op), "r" (addr))
-
-#define sync()								\
-	__asm__ __volatile(						\
-	"	.set	mips64\n\t		\n"			\
-	"	sync				\n"			\
-	"	.set	mips0")
-
-#define mispredict()							\
-	__asm__ __volatile__(						\
-	"	bnezl  $0, 1f		\n" /* Force mispredict */	\
-	"1:				\n");
-
-/*
- * Writeback and invalidate the entire dcache
- */
-static inline void __sb1_writeback_inv_dcache_all(void)
-{
-	unsigned long addr = 0;
-
-	while (addr < dcache_line_size * dcache_sets) {
-		cache_set_op(Index_Writeback_Inv_D, addr);
-		addr += dcache_line_size;
-	}
-}
-
-/*
- * Writeback and invalidate a range of the dcache.  The addresses are
- * virtual, and since we're using index ops and bit 12 is part of both
- * the virtual frame and physical index, we have to clear both sets
- * (bit 12 set and cleared).
- */
-static inline void __sb1_writeback_inv_dcache_range(unsigned long start,
-	unsigned long end)
-{
-	unsigned long index;
-
-	start &= ~(dcache_line_size - 1);
-	end = (end + dcache_line_size - 1) & ~(dcache_line_size - 1);
-
-	while (start != end) {
-		index = start & dcache_index_mask;
-		cache_set_op(Index_Writeback_Inv_D, index);
-		cache_set_op(Index_Writeback_Inv_D, index ^ (1<<12));
-		start += dcache_line_size;
-	}
-	sync();
-}
-
-/*
- * Writeback and invalidate a range of the dcache.  With physical
- * addresseses, we don't have to worry about possible bit 12 aliasing.
- * XXXKW is it worth turning on KX and using hit ops with xkphys?
- */
-static inline void __sb1_writeback_inv_dcache_phys_range(unsigned long start,
-	unsigned long end)
-{
-	start &= ~(dcache_line_size - 1);
-	end = (end + dcache_line_size - 1) & ~(dcache_line_size - 1);
-
-	while (start != end) {
-		cache_set_op(Index_Writeback_Inv_D, start & dcache_index_mask);
-		start += dcache_line_size;
-	}
-	sync();
-}
-
-
-/*
- * Invalidate the entire icache
- */
-static inline void __sb1_flush_icache_all(void)
-{
-	unsigned long addr = 0;
-
-	while (addr < icache_line_size * icache_sets) {
-		cache_set_op(Index_Invalidate_I, addr);
-		addr += icache_line_size;
-	}
-}
-
-/*
- * Invalidate a range of the icache.  The addresses are virtual, and
- * the cache is virtually indexed and tagged.  However, we don't
- * necessarily have the right ASID context, so use index ops instead
- * of hit ops.
- */
-static inline void __sb1_flush_icache_range(unsigned long start,
-	unsigned long end)
-{
-	start &= ~(icache_line_size - 1);
-	end = (end + icache_line_size - 1) & ~(icache_line_size - 1);
-
-	while (start != end) {
-		cache_set_op(Index_Invalidate_I, start & icache_index_mask);
-		start += icache_line_size;
-	}
-	mispredict();
-	sync();
-}
-
-/*
- * Flush the icache for a given physical page.  Need to writeback the
- * dcache first, then invalidate the icache.  If the page isn't
- * executable, nothing is required.
- */
-static void local_sb1_flush_cache_page(struct vm_area_struct *vma, unsigned long addr, unsigned long pfn)
-{
-	int cpu = smp_processor_id();
-
-#ifndef CONFIG_SMP
-	if (!(vma->vm_flags & VM_EXEC))
-		return;
-#endif
-
-	__sb1_writeback_inv_dcache_range(addr, addr + PAGE_SIZE);
-
-	/*
-	 * Bumping the ASID is probably cheaper than the flush ...
-	 */
-	if (vma->vm_mm == current->active_mm) {
-		if (cpu_context(cpu, vma->vm_mm) != 0)
-			drop_mmu_context(vma->vm_mm, cpu);
-	} else
-		__sb1_flush_icache_range(addr, addr + PAGE_SIZE);
-}
-
-#ifdef CONFIG_SMP
-struct flush_cache_page_args {
-	struct vm_area_struct *vma;
-	unsigned long addr;
-	unsigned long pfn;
-};
-
-static void sb1_flush_cache_page_ipi(void *info)
-{
-	struct flush_cache_page_args *args = info;
-
-	local_sb1_flush_cache_page(args->vma, args->addr, args->pfn);
-}
-
-/* Dirty dcache could be on another CPU, so do the IPIs */
-static void sb1_flush_cache_page(struct vm_area_struct *vma, unsigned long addr, unsigned long pfn)
-{
-	struct flush_cache_page_args args;
-
-	if (!(vma->vm_flags & VM_EXEC))
-		return;
-
-	addr &= PAGE_MASK;
-	args.vma = vma;
-	args.addr = addr;
-	args.pfn = pfn;
-	sb1_on_each_cpu(sb1_flush_cache_page_ipi, (void *) &args, 1, 1);
-}
-#else
-void sb1_flush_cache_page(struct vm_area_struct *vma, unsigned long addr, unsigned long pfn)
-	__attribute__((alias("local_sb1_flush_cache_page")));
-#endif
-
-#ifdef CONFIG_SMP
-static void sb1_flush_cache_data_page_ipi(void *info)
-{
-	unsigned long start = (unsigned long)info;
-
-	__sb1_writeback_inv_dcache_range(start, start + PAGE_SIZE);
-}
-
-static void sb1_flush_cache_data_page(unsigned long addr)
-{
-	if (in_atomic())
-		__sb1_writeback_inv_dcache_range(addr, addr + PAGE_SIZE);
-	else
-		on_each_cpu(sb1_flush_cache_data_page_ipi, (void *) addr, 1, 1);
-}
-#else
-
-static void local_sb1_flush_cache_data_page(unsigned long addr)
-{
-	__sb1_writeback_inv_dcache_range(addr, addr + PAGE_SIZE);
-}
-
-void sb1_flush_cache_data_page(unsigned long)
-	__attribute__((alias("local_sb1_flush_cache_data_page")));
-#endif
-
-/*
- * Invalidate all caches on this CPU
- */
-static void __used local_sb1___flush_cache_all(void)
-{
-	__sb1_writeback_inv_dcache_all();
-	__sb1_flush_icache_all();
-}
-
-#ifdef CONFIG_SMP
-void sb1___flush_cache_all_ipi(void *ignored)
-	__attribute__((alias("local_sb1___flush_cache_all")));
-
-static void sb1___flush_cache_all(void)
-{
-	sb1_on_each_cpu(sb1___flush_cache_all_ipi, 0, 1, 1);
-}
-#else
-void sb1___flush_cache_all(void)
-	__attribute__((alias("local_sb1___flush_cache_all")));
-#endif
-
-/*
- * When flushing a range in the icache, we have to first writeback
- * the dcache for the same range, so new ifetches will see any
- * data that was dirty in the dcache.
- *
- * The start/end arguments are Kseg addresses (possibly mapped Kseg).
- */
-
-static void local_sb1_flush_icache_range(unsigned long start,
-	unsigned long end)
-{
-	/* Just wb-inv the whole dcache if the range is big enough */
-	if ((end - start) > dcache_range_cutoff)
-		__sb1_writeback_inv_dcache_all();
-	else
-		__sb1_writeback_inv_dcache_range(start, end);
-
-	/* Just flush the whole icache if the range is big enough */
-	if ((end - start) > icache_range_cutoff)
-		__sb1_flush_icache_all();
-	else
-		__sb1_flush_icache_range(start, end);
-}
-
-#ifdef CONFIG_SMP
-struct flush_icache_range_args {
-	unsigned long start;
-	unsigned long end;
-};
-
-static void sb1_flush_icache_range_ipi(void *info)
-{
-	struct flush_icache_range_args *args = info;
-
-	local_sb1_flush_icache_range(args->start, args->end);
-}
-
-void sb1_flush_icache_range(unsigned long start, unsigned long end)
-{
-	struct flush_icache_range_args args;
-
-	args.start = start;
-	args.end = end;
-	sb1_on_each_cpu(sb1_flush_icache_range_ipi, &args, 1, 1);
-}
-#else
-void sb1_flush_icache_range(unsigned long start, unsigned long end)
-	__attribute__((alias("local_sb1_flush_icache_range")));
-#endif
-
-/*
- * A signal trampoline must fit into a single cacheline.
- */
-static void local_sb1_flush_cache_sigtramp(unsigned long addr)
-{
-	cache_set_op(Index_Writeback_Inv_D, addr & dcache_index_mask);
-	cache_set_op(Index_Writeback_Inv_D, (addr ^ (1<<12)) & dcache_index_mask);
-	cache_set_op(Index_Invalidate_I, addr & icache_index_mask);
-	mispredict();
-}
-
-#ifdef CONFIG_SMP
-static void sb1_flush_cache_sigtramp_ipi(void *info)
-{
-	unsigned long iaddr = (unsigned long) info;
-	local_sb1_flush_cache_sigtramp(iaddr);
-}
-
-static void sb1_flush_cache_sigtramp(unsigned long addr)
-{
-	sb1_on_each_cpu(sb1_flush_cache_sigtramp_ipi, (void *) addr, 1, 1);
-}
-#else
-void sb1_flush_cache_sigtramp(unsigned long addr)
-	__attribute__((alias("local_sb1_flush_cache_sigtramp")));
-#endif
-
-
-/*
- * Anything that just flushes dcache state can be ignored, as we're always
- * coherent in dcache space.  This is just a dummy function that all the
- * nop'ed routines point to
- */
-static void sb1_nop(void)
-{
-}
-
-/*
- *  Cache set values (from the mips64 spec)
- * 0 - 64
- * 1 - 128
- * 2 - 256
- * 3 - 512
- * 4 - 1024
- * 5 - 2048
- * 6 - 4096
- * 7 - Reserved
- */
-
-static unsigned int decode_cache_sets(unsigned int config_field)
-{
-	if (config_field == 7) {
-		/* JDCXXX - Find a graceful way to abort. */
-		return 0;
-	}
-	return (1<<(config_field + 6));
-}
-
-/*
- *  Cache line size values (from the mips64 spec)
- * 0 - No cache present.
- * 1 - 4 bytes
- * 2 - 8 bytes
- * 3 - 16 bytes
- * 4 - 32 bytes
- * 5 - 64 bytes
- * 6 - 128 bytes
- * 7 - Reserved
- */
-
-static unsigned int decode_cache_line_size(unsigned int config_field)
-{
-	if (config_field == 0) {
-		return 0;
-	} else if (config_field == 7) {
-		/* JDCXXX - Find a graceful way to abort. */
-		return 0;
-	}
-	return (1<<(config_field + 1));
-}
-
-/*
- * Relevant bits of the config1 register format (from the MIPS32/MIPS64 specs)
- *
- * 24:22 Icache sets per way
- * 21:19 Icache line size
- * 18:16 Icache Associativity
- * 15:13 Dcache sets per way
- * 12:10 Dcache line size
- * 9:7   Dcache Associativity
- */
-
-static char *way_string[] = {
-	"direct mapped", "2-way", "3-way", "4-way",
-	"5-way", "6-way", "7-way", "8-way",
-};
-
-static __init void probe_cache_sizes(void)
-{
-	u32 config1;
-
-	config1 = read_c0_config1();
-	icache_line_size = decode_cache_line_size((config1 >> 19) & 0x7);
-	dcache_line_size = decode_cache_line_size((config1 >> 10) & 0x7);
-	icache_sets = decode_cache_sets((config1 >> 22) & 0x7);
-	dcache_sets = decode_cache_sets((config1 >> 13) & 0x7);
-	icache_assoc = ((config1 >> 16) & 0x7) + 1;
-	dcache_assoc = ((config1 >> 7) & 0x7) + 1;
-	icache_size = icache_line_size * icache_sets * icache_assoc;
-	dcache_size = dcache_line_size * dcache_sets * dcache_assoc;
-	/* Need to remove non-index bits for index ops */
-	icache_index_mask = (icache_sets - 1) * icache_line_size;
-	dcache_index_mask = (dcache_sets - 1) * dcache_line_size;
-	/*
-	 * These are for choosing range (index ops) versus all.
-	 * icache flushes all ways for each set, so drop icache_assoc.
-	 * dcache flushes all ways and each setting of bit 12 for each
-	 * index, so drop dcache_assoc and halve the dcache_sets.
-	 */
-	icache_range_cutoff = icache_sets * icache_line_size;
-	dcache_range_cutoff = (dcache_sets / 2) * icache_line_size;
-
-	printk("Primary instruction cache %ldkB, %s, linesize %d bytes.\n",
-	       icache_size >> 10, way_string[icache_assoc - 1],
-	       icache_line_size);
-	printk("Primary data cache %ldkB, %s, linesize %d bytes.\n",
-	       dcache_size >> 10, way_string[dcache_assoc - 1],
-	       dcache_line_size);
-}
-
-/*
- * This is called from cache.c.  We have to set up all the
- * memory management function pointers, as well as initialize
- * the caches and tlbs
- */
-void __init sb1_cache_init(void)
-{
-	extern char except_vec2_sb1;
-
-	/* Special cache error handler for SB1 */
-	set_uncached_handler (0x100, &except_vec2_sb1, 0x80);
-
-	probe_cache_sizes();
-
-#ifdef CONFIG_SIBYTE_DMA_PAGEOPS
-	sb1_dma_init();
-#endif
-
-	/*
-	 * None of these are needed for the SB1 - the Dcache is
-	 * physically indexed and tagged, so no virtual aliasing can
-	 * occur
-	 */
-	flush_cache_range = (void *) sb1_nop;
-	flush_cache_mm = (void (*)(struct mm_struct *))sb1_nop;
-	flush_cache_all = sb1_nop;
-
-	/* These routines are for Icache coherence with the Dcache */
-	flush_icache_range = sb1_flush_icache_range;
-	flush_icache_all = __sb1_flush_icache_all; /* local only */
-
-	/* This implies an Icache flush too, so can't be nop'ed */
-	flush_cache_page = sb1_flush_cache_page;
-
-	flush_cache_sigtramp = sb1_flush_cache_sigtramp;
-	local_flush_data_cache_page = (void *) sb1_nop;
-	flush_data_cache_page = sb1_flush_cache_data_page;
-
-	/* Full flush */
-	__flush_cache_all = sb1___flush_cache_all;
-
-	change_c0_config(CONF_CM_CMASK, CONF_CM_DEFAULT);
-
-	/*
-	 * This is the only way to force the update of K0 to complete
-	 * before subsequent instruction fetch.
-	 */
-	__asm__ __volatile__(
-		".set	push			\n"
-	"	.set	noat			\n"
-	"	.set	noreorder		\n"
-	"	.set	mips3			\n"
-	"	" STR(PTR_LA) "	$1, 1f		\n"
-	"	" STR(MTC0) "	$1, $14		\n"
-	"	eret				\n"
-	"1:	.set	pop"
-	:
-	:
-	: "memory");
-
-	local_sb1___flush_cache_all();
-}
diff --git a/arch/mips/mm/cache.c b/arch/mips/mm/cache.c
index 81f925a9a731..43dde874f414 100644
--- a/arch/mips/mm/cache.c
+++ b/arch/mips/mm/cache.c
@@ -3,13 +3,14 @@
  * License.  See the file "COPYING" in the main directory of this archive
  * for more details.
  *
- * Copyright (C) 1994 - 2003, 07 by Ralf Baechle (ralf@linux-mips.org)
+ * Copyright (C) 1994 - 2003, 06, 07 by Ralf Baechle (ralf@linux-mips.org)
  * Copyright (C) 2007 MIPS Technologies, Inc.
  */
 #include <linux/fs.h>
 #include <linux/fcntl.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
+#include <linux/linkage.h>
 #include <linux/module.h>
 #include <linux/sched.h>
 #include <linux/mm.h>
@@ -157,12 +158,6 @@ void __init cpu_cache_init(void)
 		tx39_cache_init();
 		return;
 	}
-	if (cpu_has_sb1_cache) {
-		extern void __weak sb1_cache_init(void);
-
-		sb1_cache_init();
-		return;
-	}
 
 	panic(cache_panic);
 }
diff --git a/arch/mips/mm/pg-sb1.c b/arch/mips/mm/pg-sb1.c
index adb37d0a30ea..82f42ace73c8 100644
--- a/arch/mips/mm/pg-sb1.c
+++ b/arch/mips/mm/pg-sb1.c
@@ -292,3 +292,11 @@ void copy_page(void *to, void *from)
 
 EXPORT_SYMBOL(clear_page);
 EXPORT_SYMBOL(copy_page);
+
+void __init build_clear_page(void)
+{
+}
+
+void __init build_copy_page(void)
+{
+}