Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 184 insertions, 0 deletions

diff --git a/arch/arm/mm/blockops.c b/arch/arm/mm/blockops.c
new file mode 100644
index 0000000..806c6ee
--- /dev/null
+++ b/arch/arm/mm/blockops.c
@@ -0,0 +1,184 @@
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/mm.h>
+
+#include <asm/memory.h>
+#include <asm/ptrace.h>
+#include <asm/cacheflush.h>
+#include <asm/traps.h>
+
+extern struct cpu_cache_fns blk_cache_fns;
+
+#define HARVARD_CACHE
+
+/*
+ *	blk_flush_kern_dcache_page(kaddr)
+ *
+ *	Ensure that the data held in the page kaddr is written back
+ *	to the page in question.
+ *
+ *	- kaddr   - kernel address (guaranteed to be page aligned)
+ */
+static void __attribute__((naked))
+blk_flush_kern_dcache_page(void *kaddr)
+{
+	asm(
+	"add	r1, r0, %0							\n\
+1:	.word	0xec401f0e	@ mcrr	p15, 0, r0, r1, c14, 0	@ blocking	\n\
+	mov	r0, #0								\n\
+	mcr	p15, 0, r0, c7, c5, 0						\n\
+	mcr	p15, 0, r0, c7, c10, 4						\n\
+	mov	pc, lr"
+	:
+	: "I" (PAGE_SIZE));
+}
+
+/*
+ *	blk_dma_inv_range(start,end)
+ *
+ *	Invalidate the data cache within the specified region; we will
+ *	be performing a DMA operation in this region and we want to
+ *	purge old data in the cache.
+ *
+ *	- start   - virtual start address of region
+ *	- end     - virtual end address of region
+ */
+static void __attribute__((naked))
+blk_dma_inv_range_unified(unsigned long start, unsigned long end)
+{
+	asm(
+	"tst	r0, %0								\n\
+	mcrne	p15, 0, r0, c7, c11, 1		@ clean unified line		\n\
+	tst	r1, %0								\n\
+	mcrne	p15, 0, r1, c7, c15, 1		@ clean & invalidate unified line\n\
+	.word	0xec401f06	@ mcrr	p15, 0, r1, r0, c6, 0	@ blocking	\n\
+	mov	r0, #0								\n\
+	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer		\n\
+	mov	pc, lr"
+	:
+	: "I" (L1_CACHE_BYTES - 1));
+}
+
+static void __attribute__((naked))
+blk_dma_inv_range_harvard(unsigned long start, unsigned long end)
+{
+	asm(
+	"tst	r0, %0								\n\
+	mcrne	p15, 0, r0, c7, c10, 1		@ clean D line			\n\
+	tst	r1, %0								\n\
+	mcrne	p15, 0, r1, c7, c14, 1		@ clean & invalidate D line	\n\
+	.word	0xec401f06	@ mcrr	p15, 0, r1, r0, c6, 0	@ blocking	\n\
+	mov	r0, #0								\n\
+	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer		\n\
+	mov	pc, lr"
+	:
+	: "I" (L1_CACHE_BYTES - 1));
+}
+
+/*
+ *	blk_dma_clean_range(start,end)
+ *	- start   - virtual start address of region
+ *	- end     - virtual end address of region
+ */
+static void __attribute__((naked))
+blk_dma_clean_range(unsigned long start, unsigned long end)
+{
+	asm(
+	".word	0xec401f0c	@ mcrr	p15, 0, r1, r0, c12, 0	@ blocking	\n\
+	mov	r0, #0								\n\
+	mcr	p15, 0, r0, c7, c10, 4		@ drain write buffer		\n\
+	mov	pc, lr");
+}
+
+/*
+ *	blk_dma_flush_range(start,end)
+ *	- start   - virtual start address of region
+ *	- end     - virtual end address of region
+ */
+static void __attribute__((naked))
+blk_dma_flush_range(unsigned long start, unsigned long end)
+{
+	asm(
+	".word	0xec401f0e	@ mcrr	p15, 0, r1, r0, c14, 0	@ blocking	\n\
+	mov	pc, lr");
+}
+
+static int blockops_trap(struct pt_regs *regs, unsigned int instr)
+{
+	regs->ARM_r4 |= regs->ARM_r2;
+	regs->ARM_pc += 4;
+	return 0;
+}
+
+static char *func[] = {
+	"Prefetch data range",
+	"Clean+Invalidate data range",
+	"Clean data range",
+	"Invalidate data range",
+	"Invalidate instr range"
+};
+
+static struct undef_hook blockops_hook __initdata = {
+	.instr_mask	= 0x0fffffd0,
+	.instr_val	= 0x0c401f00,
+	.cpsr_mask	= PSR_T_BIT,
+	.cpsr_val	= 0,
+	.fn		= blockops_trap,
+};
+
+static int __init blockops_check(void)
+{
+	register unsigned int err asm("r4") = 0;
+	unsigned int err_pos = 1;
+	unsigned int cache_type;
+	int i;
+
+	asm("mrc p15, 0, %0, c0, c0, 1" : "=r" (cache_type));
+
+	printk("Checking V6 block cache operations:\n");
+	register_undef_hook(&blockops_hook);
+
+	__asm__ ("mov	r0, %0\n\t"
+		"mov	r1, %1\n\t"
+		"mov	r2, #1\n\t"
+		".word	0xec401f2c @ mcrr p15, 0, r1, r0, c12, 2\n\t"
+		"mov	r2, #2\n\t"
+		".word	0xec401f0e @ mcrr p15, 0, r1, r0, c14, 0\n\t"
+		"mov	r2, #4\n\t"
+		".word	0xec401f0c @ mcrr p15, 0, r1, r0, c12, 0\n\t"
+		"mov	r2, #8\n\t"
+		".word	0xec401f06 @ mcrr p15, 0, r1, r0, c6, 0\n\t"
+		"mov	r2, #16\n\t"
+		".word	0xec401f05 @ mcrr p15, 0, r1, r0, c5, 0\n\t"
+		:
+		: "r" (PAGE_OFFSET), "r" (PAGE_OFFSET + 128)
+		: "r0", "r1", "r2");
+
+	unregister_undef_hook(&blockops_hook);
+
+	for (i = 0; i < ARRAY_SIZE(func); i++, err_pos <<= 1)
+		printk("%30s: %ssupported\n", func[i], err & err_pos ? "not " : "");
+
+	if ((err & 8) == 0) {
+		printk(" --> Using %s block cache invalidate\n",
+			cache_type & (1 << 24) ? "harvard" : "unified");
+		if (cache_type & (1 << 24))
+			cpu_cache.dma_inv_range = blk_dma_inv_range_harvard;
+		else
+			cpu_cache.dma_inv_range = blk_dma_inv_range_unified;
+	}
+	if ((err & 4) == 0) {
+		printk(" --> Using block cache clean\n");
+		cpu_cache.dma_clean_range        = blk_dma_clean_range;
+	}
+	if ((err & 2) == 0) {
+		printk(" --> Using block cache clean+invalidate\n");
+		cpu_cache.dma_flush_range        = blk_dma_flush_range;
+		cpu_cache.flush_kern_dcache_page = blk_flush_kern_dcache_page;
+	}
+
+	return 0;
+}
+
+__initcall(blockops_check);