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authorLee Jones <lee.jones@linaro.org>2014-03-20 09:20:46 +0000
committerBrian Norris <computersforpeace@gmail.com>2014-03-20 04:17:17 -0700
commita63984c18a6186a323987817f01095d07503bda1 (patch)
treeda4a0da3d013be82943b04b5159b39fc94071489 /drivers/mtd/devices
parente209e1e8e330b55feaa16ed62836e3665026e406 (diff)
downloadop-kernel-dev-a63984c18a6186a323987817f01095d07503bda1.zip
op-kernel-dev-a63984c18a6186a323987817f01095d07503bda1.tar.gz
mtd: st_spi_fsm: Fetch boot-device from mode pins
It's important for us to determine which device was used to boot from in order to make some correct decisions surrounding Power Management. On each of the platforms which support the FSM this is communicated via a set of mode pins held in the system configuration area. This patch determine the boot device and stores the result. Acked-by Angus Clark <angus.clark@st.com> Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Diffstat (limited to 'drivers/mtd/devices')
-rw-r--r--drivers/mtd/devices/st_spi_fsm.c46
1 files changed, 46 insertions, 0 deletions
diff --git a/drivers/mtd/devices/st_spi_fsm.c b/drivers/mtd/devices/st_spi_fsm.c
index 83cf9df..6be2672 100644
--- a/drivers/mtd/devices/st_spi_fsm.c
+++ b/drivers/mtd/devices/st_spi_fsm.c
@@ -14,7 +14,9 @@
*/
#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/regmap.h>
#include <linux/platform_device.h>
+#include <linux/mfd/syscon.h>
#include <linux/mtd/mtd.h>
#include <linux/sched.h>
#include <linux/delay.h>
@@ -207,6 +209,7 @@ struct stfsm {
struct flash_info *info;
uint32_t fifo_dir_delay;
+ bool booted_from_spi;
};
struct stfsm_seq {
@@ -692,6 +695,47 @@ static int stfsm_init(struct stfsm *fsm)
return 0;
}
+static void stfsm_fetch_platform_configs(struct platform_device *pdev)
+{
+ struct stfsm *fsm = platform_get_drvdata(pdev);
+ struct device_node *np = pdev->dev.of_node;
+ struct regmap *regmap;
+ uint32_t boot_device_reg;
+ uint32_t boot_device_spi;
+ uint32_t boot_device; /* Value we read from *boot_device_reg */
+ int ret;
+
+ /* Booting from SPI NOR Flash is the default */
+ fsm->booted_from_spi = true;
+
+ regmap = syscon_regmap_lookup_by_phandle(np, "st,syscfg");
+ if (IS_ERR(regmap))
+ goto boot_device_fail;
+
+ /* Where in the syscon the boot device information lives */
+ ret = of_property_read_u32(np, "st,boot-device-reg", &boot_device_reg);
+ if (ret)
+ goto boot_device_fail;
+
+ /* Boot device value when booted from SPI NOR */
+ ret = of_property_read_u32(np, "st,boot-device-spi", &boot_device_spi);
+ if (ret)
+ goto boot_device_fail;
+
+ ret = regmap_read(regmap, boot_device_reg, &boot_device);
+ if (ret)
+ goto boot_device_fail;
+
+ if (boot_device != boot_device_spi)
+ fsm->booted_from_spi = false;
+
+ return;
+
+boot_device_fail:
+ dev_warn(&pdev->dev,
+ "failed to fetch boot device, assuming boot from SPI\n");
+}
+
static int stfsm_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
@@ -734,6 +778,8 @@ static int stfsm_probe(struct platform_device *pdev)
return ret;
}
+ stfsm_fetch_platform_configs(pdev);
+
/* Detect SPI FLASH device */
info = stfsm_jedec_probe(fsm);
if (!info)
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