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authorAnson Huang <b20788@freescale.com>2014-02-12 13:57:03 +0400
committerShawn Guo <shawn.guo@linaro.org>2014-03-05 06:35:22 +0400
commitc962a0996335fae7f79e64677f47d4784b86f692 (patch)
tree350dd1ec2dd2322b22b08a348d07700c36168bf4
parent6e6cdf66563086cb0d2071a4c8ecad7b236ce3ec (diff)
downloadlinux-c962a0996335fae7f79e64677f47d4784b86f692.tar.xz
ARM: imx: add speed grading check for i.mx6 soc
The fuse map of speed_grading[1:0] defines the max speed of ARM, see below the definition: 2b'11: 1200000000Hz; 2b'10: 996000000Hz; 2b'01: 852000000Hz; -- i.MX6Q Only, exclusive with 996MHz. 2b'00: 792000000Hz; Need to remove all illegal setpoints according to fuse map. Signed-off-by: Anson Huang <b20788@freescale.com> Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
-rw-r--r--arch/arm/mach-imx/mach-imx6q.c26
1 files changed, 23 insertions, 3 deletions
diff --git a/arch/arm/mach-imx/mach-imx6q.c b/arch/arm/mach-imx/mach-imx6q.c
index d131499be5d3..1e126853847c 100644
--- a/arch/arm/mach-imx/mach-imx6q.c
+++ b/arch/arm/mach-imx/mach-imx6q.c
@@ -253,8 +253,10 @@ static void __init imx6q_init_machine(void)
#define OCOTP_CFG3 0x440
#define OCOTP_CFG3_SPEED_SHIFT 16
#define OCOTP_CFG3_SPEED_1P2GHZ 0x3
+#define OCOTP_CFG3_SPEED_996MHZ 0x2
+#define OCOTP_CFG3_SPEED_852MHZ 0x1
-static void __init imx6q_opp_check_1p2ghz(struct device *cpu_dev)
+static void __init imx6q_opp_check_speed_grading(struct device *cpu_dev)
{
struct device_node *np;
void __iomem *base;
@@ -272,11 +274,29 @@ static void __init imx6q_opp_check_1p2ghz(struct device *cpu_dev)
goto put_node;
}
+ /*
+ * SPEED_GRADING[1:0] defines the max speed of ARM:
+ * 2b'11: 1200000000Hz;
+ * 2b'10: 996000000Hz;
+ * 2b'01: 852000000Hz; -- i.MX6Q Only, exclusive with 996MHz.
+ * 2b'00: 792000000Hz;
+ * We need to set the max speed of ARM according to fuse map.
+ */
val = readl_relaxed(base + OCOTP_CFG3);
val >>= OCOTP_CFG3_SPEED_SHIFT;
- if ((val & 0x3) != OCOTP_CFG3_SPEED_1P2GHZ)
+ val &= 0x3;
+
+ if (val != OCOTP_CFG3_SPEED_1P2GHZ)
if (dev_pm_opp_disable(cpu_dev, 1200000000))
pr_warn("failed to disable 1.2 GHz OPP\n");
+ if (val < OCOTP_CFG3_SPEED_996MHZ)
+ if (dev_pm_opp_disable(cpu_dev, 996000000))
+ pr_warn("failed to disable 996 MHz OPP\n");
+ if (cpu_is_imx6q()) {
+ if (val != OCOTP_CFG3_SPEED_852MHZ)
+ if (dev_pm_opp_disable(cpu_dev, 852000000))
+ pr_warn("failed to disable 852 MHz OPP\n");
+ }
put_node:
of_node_put(np);
@@ -302,7 +322,7 @@ static void __init imx6q_opp_init(void)
goto put_node;
}
- imx6q_opp_check_1p2ghz(cpu_dev);
+ imx6q_opp_check_speed_grading(cpu_dev);
put_node:
of_node_put(np);