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-rw-r--r--arch/arm/mach-omap1/sram-init.c145
1 files changed, 145 insertions, 0 deletions
diff --git a/arch/arm/mach-omap1/sram-init.c b/arch/arm/mach-omap1/sram-init.c
new file mode 100644
index 0000000000..736a72a2b1
--- /dev/null
+++ b/arch/arm/mach-omap1/sram-init.c
@@ -0,0 +1,145 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * OMAP SRAM detection and management
+ *
+ * Copyright (C) 2005 Nokia Corporation
+ * Written by Tony Lindgren <tony@atomide.com>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/set_memory.h>
+
+#include <asm/fncpy.h>
+#include <asm/tlb.h>
+#include <asm/cacheflush.h>
+
+#include <asm/mach/map.h>
+
+#include "soc.h"
+#include "sram.h"
+
+#define OMAP1_SRAM_PA 0x20000000
+#define SRAM_BOOTLOADER_SZ 0x80
+#define ROUND_DOWN(value, boundary) ((value) & (~((boundary) - 1)))
+
+static void __iomem *omap_sram_base;
+static unsigned long omap_sram_start;
+static unsigned long omap_sram_skip;
+static unsigned long omap_sram_size;
+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 __force *)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_rox(base, pages);
+
+ return dst;
+}
+
+/*
+ * The amount of SRAM depends on the core type.
+ * Note that we cannot try to test for SRAM here because writes
+ * to secure SRAM will hang the system. Also the SRAM is not
+ * yet mapped at this point.
+ * Note that we cannot use ioremap for SRAM, as clock init needs SRAM early.
+ */
+static void __init omap_detect_and_map_sram(void)
+{
+ unsigned long base;
+ int pages;
+
+ omap_sram_skip = SRAM_BOOTLOADER_SZ;
+ omap_sram_start = OMAP1_SRAM_PA;
+
+ if (cpu_is_omap15xx())
+ omap_sram_size = 0x30000; /* 192K */
+ else if (cpu_is_omap1610() || cpu_is_omap1611() ||
+ cpu_is_omap1621() || cpu_is_omap1710())
+ omap_sram_size = 0x4000; /* 16K */
+ else {
+ pr_err("Could not detect SRAM size\n");
+ omap_sram_size = 0x4000;
+ }
+
+ omap_sram_start = ROUND_DOWN(omap_sram_start, PAGE_SIZE);
+ omap_sram_base = __arm_ioremap_exec(omap_sram_start, omap_sram_size, 1);
+ if (!omap_sram_base) {
+ pr_err("SRAM: Could not map\n");
+ return;
+ }
+
+ omap_sram_ceil = omap_sram_base + omap_sram_size;
+
+ /*
+ * 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_rox(base, pages);
+}
+
+static void (*_omap_sram_reprogram_clock)(u32 dpllctl, u32 ckctl);
+
+void omap_sram_reprogram_clock(u32 dpllctl, u32 ckctl)
+{
+ BUG_ON(!_omap_sram_reprogram_clock);
+ _omap_sram_reprogram_clock(dpllctl, ckctl);
+}
+
+int __init omap1_sram_init(void)
+{
+ omap_detect_and_map_sram();
+ _omap_sram_reprogram_clock =
+ omap_sram_push(omap1_sram_reprogram_clock,
+ omap1_sram_reprogram_clock_sz);
+
+ return 0;
+}