ARM: omap: un-merge plat/sram.c

The sram initialization code is the only shared omap1/2 code that
is not a standalone driver, but it is very short. Having two copies
of this code means some duplication of the sources, but actually
saves object code size as it can be inlined better.

Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

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,