From bcd97dbdcb7bc0300397db481872252e8849307b Mon Sep 17 00:00:00 2001
From: John Crispin <blogic@openwrt.org>
Date: Mon, 25 Mar 2013 10:50:53 +0100
Subject: [PATCH 207/208] owrt: MIPS: ralink: add support for runtime memory
detection
This allows us to add a device_node called "memorydetect" to the DT with
information about the memory windoe of the SoC. Based on this the memory is
detected ar runtime.
Signed-off-by: John Crispin <blogic@openwrt.org>
---
arch/mips/include/asm/prom.h | 3 ++
arch/mips/kernel/prom.c | 3 ++
arch/mips/ralink/Makefile | 2 +-
arch/mips/ralink/memory.c | 119 ++++++++++++++++++++++++++++++++++++++++++
4 files changed, 126 insertions(+), 1 deletion(-)
create mode 100644 arch/mips/ralink/memory.c
--- a/arch/mips/include/asm/prom.h
+++ b/arch/mips/include/asm/prom.h
@@ -20,6 +20,9 @@
extern int early_init_dt_scan_memory_arch(unsigned long node,
const char *uname, int depth, void *data);
+extern int early_init_dt_detect_memory(unsigned long node,
+ const char *uname, int depth, void *data);
+
extern void device_tree_init(void);
static inline unsigned long pci_address_to_pio(phys_addr_t address)
--- a/arch/mips/kernel/prom.c
+++ b/arch/mips/kernel/prom.c
@@ -88,6 +88,9 @@ void __init early_init_devtree(void *par
of_scan_flat_dt(early_init_dt_scan_memory_arch, NULL);
/* try to load the mips machine name */
+ of_scan_flat_dt(early_init_dt_detect_memory, NULL);
+
+ /* try to load the mips machine name */
of_scan_flat_dt(early_init_dt_scan_model, NULL);
}
--- a/arch/mips/ralink/Makefile
+++ b/arch/mips/ralink/Makefile
@@ -6,7 +6,7 @@
# Copyright (C) 2009-2011 Gabor Juhos <juhosg@openwrt.org>
# Copyright (C) 2013 John Crispin <blogic@openwrt.org>
-obj-y := prom.o of.o reset.o clk.o irq.o pinmux.o timer.o
+obj-y := prom.o of.o reset.o clk.o irq.o pinmux.o timer.o memory.o
obj-$(CONFIG_SOC_RT288X) += rt288x.o
obj-$(CONFIG_SOC_RT305X) += rt305x.o rt305x-usb.o
--- /dev/null
+++ b/arch/mips/ralink/memory.c
@@ -0,0 +1,119 @@
+/*
+ * 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.
+ *
+ * Copyright (C) 2009 Gabor Juhos <juhosg@openwrt.org>
+ * Copyright (C) 2013 John Crispin <blogic@openwrt.org>
+ */
+
+#include <linux/string.h>
+#include <linux/of_fdt.h>
+#include <linux/of_platform.h>
+
+#include <asm/bootinfo.h>
+#include <asm/addrspace.h>
+
+#include "common.h"
+
+#define MB (1024 * 1024)
+
+unsigned long ramips_mem_base;
+unsigned long ramips_mem_size_min;
+unsigned long ramips_mem_size_max;
+
+#ifdef CONFIG_SOC_RT305X
+
+#include <asm/mach-ralink/rt305x.h>
+
+static unsigned long rt5350_get_mem_size(void)
+{
+ void __iomem *sysc = (void __iomem *) KSEG1ADDR(RT305X_SYSC_BASE);
+ unsigned long ret;
+ u32 t;
+
+ t = __raw_readl(sysc + SYSC_REG_SYSTEM_CONFIG);
+ t = (t >> RT5350_SYSCFG0_DRAM_SIZE_SHIFT) &
+ RT5350_SYSCFG0_DRAM_SIZE_MASK;
+
+ switch (t) {
+ case RT5350_SYSCFG0_DRAM_SIZE_2M:
+ ret = 2 * 1024 * 1024;
+ break;
+ case RT5350_SYSCFG0_DRAM_SIZE_8M:
+ ret = 8 * 1024 * 1024;
+ break;
+ case RT5350_SYSCFG0_DRAM_SIZE_16M:
+ ret = 16 * 1024 * 1024;
+ break;
+ case RT5350_SYSCFG0_DRAM_SIZE_32M:
+ ret = 32 * 1024 * 1024;
+ break;
+ case RT5350_SYSCFG0_DRAM_SIZE_64M:
+ ret = 64 * 1024 * 1024;
+ break;
+ default:
+ panic("rt5350: invalid DRAM size: %u", t);
+ break;
+ }
+
+ return ret;
+}
+
+#endif
+
+static void __init detect_mem_size(void)
+{
+ unsigned long size;
+
+#ifdef CONFIG_SOC_RT305X
+ if (soc_is_rt5350()) {
+ size = rt5350_get_mem_size();
+ } else
+#endif
+ {
+ void *base;
+
+ base = (void *) KSEG1ADDR(detect_mem_size);
+ for (size = ramips_mem_size_min; size < ramips_mem_size_max;
+ size <<= 1 ) {
+ if (!memcmp(base, base + size, 1024))
+ break;
+ }
+ }
+
+ pr_info("memory detected: %uMB\n", (unsigned int) size / MB);
+
+ add_memory_region(ramips_mem_base, size, BOOT_MEM_RAM);
+}
+
+int __init early_init_dt_detect_memory(unsigned long node, const char *uname,
+ int depth, void *data)
+{
+ unsigned long l;
+ __be32 *mem;
+
+ /* We are scanning "memorydetect" nodes only */
+ if (depth != 1 || strcmp(uname, "memorydetect") != 0)
+ return 0;
+
+ mem = of_get_flat_dt_prop(node, "ralink,memory", &l);
+ if (mem == NULL)
+ return 0;
+
+ if ((l / sizeof(__be32)) != 3)
+ panic("invalid memorydetect node\n");
+
+ ramips_mem_base = dt_mem_next_cell(dt_root_addr_cells, &mem);
+ ramips_mem_size_min = dt_mem_next_cell(dt_root_size_cells, &mem);
+ ramips_mem_size_max = dt_mem_next_cell(dt_root_size_cells, &mem);
+
+ pr_info("memory window: 0x%llx, min: %uMB, max: %uMB\n",
+ (unsigned long long) ramips_mem_base,
+ (unsigned int) ramips_mem_size_min / MB,
+ (unsigned int) ramips_mem_size_max / MB);
+
+ detect_mem_size();
+
+ return 0;
+}