summaryrefslogtreecommitdiff
path: root/arch/arm/mach-omap2/sram.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/mach-omap2/sram.c')
-rw-r--r--arch/arm/mach-omap2/sram.c91
1 files changed, 88 insertions, 3 deletions
diff --git a/arch/arm/mach-omap2/sram.c b/arch/arm/mach-omap2/sram.c
index c98855f5594b..c685afb8bd03 100644
--- a/arch/arm/mach-omap2/sram.c
+++ b/arch/arm/mach-omap2/sram.c
@@ -18,6 +18,7 @@
#include <asm/fncpy.h>
#include <asm/tlb.h>
#include <asm/cacheflush.h>
+#include <asm/set_memory.h>
#include <asm/mach/map.h>
@@ -47,8 +48,68 @@
#define ROUND_DOWN(value,boundary) ((value) & (~((boundary)-1)))
static unsigned long omap_sram_start;
-static unsigned long omap_sram_skip;
static unsigned long omap_sram_size;
+static void __iomem *omap_sram_base;
+static unsigned long omap_sram_skip;
+static void __iomem *omap_sram_ceil;
+
+/*
+ * Memory allocator for SRAM: calculates the new ceiling address
+ * for pushing a function using the fncpy API.
+ *
+ * Note that fncpy requires the returned address to be aligned
+ * to an 8-byte boundary.
+ */
+static void *omap_sram_push_address(unsigned long size)
+{
+ unsigned long available, new_ceil = (unsigned long)omap_sram_ceil;
+
+ available = omap_sram_ceil - (omap_sram_base + omap_sram_skip);
+
+ if (size > available) {
+ pr_err("Not enough space in SRAM\n");
+ return NULL;
+ }
+
+ new_ceil -= size;
+ new_ceil = ROUND_DOWN(new_ceil, FNCPY_ALIGN);
+ omap_sram_ceil = IOMEM(new_ceil);
+
+ return (void *)omap_sram_ceil;
+}
+
+void *omap_sram_push(void *funcp, unsigned long size)
+{
+ void *sram;
+ unsigned long base;
+ int pages;
+ void *dst = NULL;
+
+ sram = omap_sram_push_address(size);
+ if (!sram)
+ return NULL;
+
+ base = (unsigned long)sram & PAGE_MASK;
+ pages = PAGE_ALIGN(size) / PAGE_SIZE;
+
+ set_memory_rw(base, pages);
+
+ dst = fncpy(sram, funcp, size);
+
+ set_memory_ro(base, pages);
+ set_memory_x(base, pages);
+
+ return dst;
+}
+
+/*
+ * The SRAM context is lost during off-idle and stack
+ * needs to be reset.
+ */
+static void omap_sram_reset(void)
+{
+ omap_sram_ceil = omap_sram_base + omap_sram_size;
+}
/*
* Depending on the target RAMFS firewall setup, the public usable amount of
@@ -119,6 +180,8 @@ static void __init omap_detect_sram(void)
*/
static void __init omap2_map_sram(void)
{
+ unsigned long base;
+ int pages;
int cached = 1;
if (cpu_is_omap34xx()) {
@@ -132,8 +195,30 @@ static void __init omap2_map_sram(void)
cached = 0;
}
- omap_map_sram(omap_sram_start, omap_sram_size,
- omap_sram_skip, cached);
+ if (omap_sram_size == 0)
+ return;
+
+ omap_sram_start = ROUND_DOWN(omap_sram_start, PAGE_SIZE);
+ omap_sram_base = __arm_ioremap_exec(omap_sram_start, omap_sram_size, cached);
+ if (!omap_sram_base) {
+ pr_err("SRAM: Could not map\n");
+ return;
+ }
+
+ omap_sram_reset();
+
+ /*
+ * Looks like we need to preserve some bootloader code at the
+ * beginning of SRAM for jumping to flash for reboot to work...
+ */
+ memset_io(omap_sram_base + omap_sram_skip, 0,
+ omap_sram_size - omap_sram_skip);
+
+ base = (unsigned long)omap_sram_base;
+ pages = PAGE_ALIGN(omap_sram_size) / PAGE_SIZE;
+
+ set_memory_ro(base, pages);
+ set_memory_x(base, pages);
}
static void (*_omap2_sram_ddr_init)(u32 *slow_dll_ctrl, u32 fast_dll_ctrl,