[PATCH 1/2] at91: sam9260/sam9g20/sam9261/sam9g10/sam9263 add autodetect sdram size

[Jean-Christophe PLAGNIOL-VILLARD]

if 0 is passed to at91_add_device_sdram autodetect the sdram size

The amount of available ram is determined by the SDRAMC_CR register.

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj at jcrosoft.com>
---
 arch/arm/mach-at91/at91sam9260_devices.c          |    4 +++
 arch/arm/mach-at91/at91sam9261_devices.c          |    4 +++
 arch/arm/mach-at91/at91sam9263_devices.c          |    4 +++
 arch/arm/mach-at91/include/mach/at91sam9_sdramc.h |   28 +++++++++++++++++++++
 4 files changed, 40 insertions(+)

diff --git a/arch/arm/mach-at91/at91sam9260_devices.c b/arch/arm/mach-at91/at91sam9260_devices.c
index b56ca14..9c9534e 100644
--- a/arch/arm/mach-at91/at91sam9260_devices.c
+++ b/arch/arm/mach-at91/at91sam9260_devices.c
@@ -16,6 +16,7 @@
 #include <mach/board.h>
 #include <mach/at91_pmc.h>
 #include <mach/at91sam9260_matrix.h>
+#include <mach/at91sam9_sdramc.h>
 #include <mach/gpio.h>
 #include <mach/io.h>
 #include <mach/cpu.h>
@@ -24,6 +25,9 @@
 
 void at91_add_device_sdram(u32 size)
 {
+	if (!size)
+		size = at91_get_sdram_size();
+
 	arm_add_mem_device("ram0", AT91_CHIPSELECT_1, size);
 	if (cpu_is_at91sam9g20()) {
 		add_mem_device("sram0", AT91SAM9G20_SRAM_BASE,
diff --git a/arch/arm/mach-at91/at91sam9261_devices.c b/arch/arm/mach-at91/at91sam9261_devices.c
index a109804..0091e2d 100644
--- a/arch/arm/mach-at91/at91sam9261_devices.c
+++ b/arch/arm/mach-at91/at91sam9261_devices.c
@@ -15,6 +15,7 @@
 #include <asm/hardware.h>
 #include <mach/at91_pmc.h>
 #include <mach/at91sam9261_matrix.h>
+#include <mach/at91sam9_sdramc.h>
 #include <mach/board.h>
 #include <mach/gpio.h>
 #include <mach/io.h>
@@ -24,6 +25,9 @@
 
 void at91_add_device_sdram(u32 size)
 {
+	if (!size)
+		size = at91_get_sdram_size();
+
 	arm_add_mem_device("ram0", AT91_CHIPSELECT_1, size);
 	if (cpu_is_at91sam9g10())
 		add_mem_device("sram0", AT91SAM9G10_SRAM_BASE,
diff --git a/arch/arm/mach-at91/at91sam9263_devices.c b/arch/arm/mach-at91/at91sam9263_devices.c
index 7f916d2..e686480 100644
--- a/arch/arm/mach-at91/at91sam9263_devices.c
+++ b/arch/arm/mach-at91/at91sam9263_devices.c
@@ -15,6 +15,7 @@
 #include <asm/hardware.h>
 #include <mach/at91_pmc.h>
 #include <mach/at91sam9263_matrix.h>
+#include <mach/at91sam9_sdramc.h>
 #include <mach/board.h>
 #include <mach/gpio.h>
 #include <mach/io.h>
@@ -23,6 +24,9 @@
 
 void at91_add_device_sdram(u32 size)
 {
+	if (!size)
+		size = at91_get_sdram_size();
+
 	arm_add_mem_device("ram0", AT91_CHIPSELECT_1, size);
 	add_mem_device("sram0", AT91SAM9263_SRAM0_BASE,
 			AT91SAM9263_SRAM0_SIZE, IORESOURCE_MEM_WRITEABLE);
diff --git a/arch/arm/mach-at91/include/mach/at91sam9_sdramc.h b/arch/arm/mach-at91/include/mach/at91sam9_sdramc.h
index 5af2b54..1ab61e9 100644
--- a/arch/arm/mach-at91/include/mach/at91sam9_sdramc.h
+++ b/arch/arm/mach-at91/include/mach/at91sam9_sdramc.h
@@ -83,5 +83,33 @@
 #define			AT91_SDRAMC_MD_SDRAM		0
 #define			AT91_SDRAMC_MD_LOW_POWER_SDRAM	1
 
+#ifndef __ASSEMBLY__
+#include <mach/io.h>
+static inline u32 at91_get_sdram_size(void)
+{
+	u32 val;
+	u32 size;
+
+	val = at91_sys_read(AT91_SDRAMC_CR);
+
+	/* Formula:
+	 * size = bank << (col + row + 1);
+	 * if (bandwidth == 32 bits)
+	 *	size <<= 1;
+	 */
+	size = 1;
+	/* COL */
+	size += (val & AT91_SDRAMC_NC) + 8;
+	/* ROW */
+	size += ((val & AT91_SDRAMC_NR) >> 2) + 11;
+	/* BANK */
+	size = ((val & AT91_SDRAMC_NB) ? 4 : 2) << size;
+	/* bandwidth */
+	if (!(val & AT91_SDRAMC_DBW))
+		size <<= 1;
+
+	return size;
+}
+#endif
 
 #endif
-- 
1.7.10.4