avr32: Add simple SRAM allocator

Add SRAM allocator for avr32, which is just a thin wrapper around
genalloc.
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>

arch/avr32/Kconfig

@@ -88,6 +88,7 @@ config PLATFORM_AT32AP
 	select MMU
 	select PERFORMANCE_COUNTERS
 	select HAVE_GPIO_LIB
+	select GENERIC_ALLOCATOR
 
 #
 # CPU types

arch/avr32/mach-at32ap/at32ap700x.c

@@ -20,6 +20,7 @@
 #include <asm/arch/at32ap700x.h>
 #include <asm/arch/board.h>
 #include <asm/arch/portmux.h>
+#include <asm/arch/sram.h>
 
 #include <video/atmel_lcdc.h>
 
@@ -2120,3 +2121,28 @@ void __init setup_platform(void)
 	at32_init_pio(&pio3_device);
 	at32_init_pio(&pio4_device);
 }
+
+struct gen_pool *sram_pool;
+
+static int __init sram_init(void)
+{
+	struct gen_pool *pool;
+
+	/* 1KiB granularity */
+	pool = gen_pool_create(10, -1);
+	if (!pool)
+		goto fail;
+
+	if (gen_pool_add(pool, 0x24000000, 0x8000, -1))
+		goto err_pool_add;
+
+	sram_pool = pool;
+	return 0;
+
+err_pool_add:
+	gen_pool_destroy(pool);
+fail:
+	pr_err("Failed to create SRAM pool\n");
+	return -ENOMEM;
+}
+core_initcall(sram_init);

include/asm-avr32/arch-at32ap/sram.h

+/*
+ * Simple SRAM allocator
+ *
+ * Copyright (C) 2008 Atmel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef __ASM_AVR32_ARCH_SRAM_H
+#define __ASM_AVR32_ARCH_SRAM_H
+
+#include <linux/genalloc.h>
+
+extern struct gen_pool *sram_pool;
+
+static inline unsigned long sram_alloc(size_t len)
+{
+	if (!sram_pool)
+		return 0UL;
+
+	return gen_pool_alloc(sram_pool, len);
+}
+
+static inline void sram_free(unsigned long addr, size_t len)
+{
+	return gen_pool_free(sram_pool, addr, len);
+}
+
+#endif /* __ASM_AVR32_ARCH_SRAM_H */