[PATCH 7/7] arm: zynq: Add support for cpufreq

Soren Brinkmann soren.brinkmann at xilinx.com
Fri Nov 8 16:21:17 EST 2013


The generic cpufreq-cpu0 driver can scale the CPU frequency on Zynq
SOCs. Add the required platform device to the BSP and appropriate
OPPs to the dts.

Signed-off-by: Soren Brinkmann <soren.brinkmann at xilinx.com>
---
 arch/arm/boot/dts/zynq-7000.dtsi | 6 ++++++
 arch/arm/mach-zynq/Kconfig       | 2 ++
 arch/arm/mach-zynq/common.c      | 3 +++
 3 files changed, 11 insertions(+)

diff --git a/arch/arm/boot/dts/zynq-7000.dtsi b/arch/arm/boot/dts/zynq-7000.dtsi
index 37fc04525142..aca41ca6de1d 100644
--- a/arch/arm/boot/dts/zynq-7000.dtsi
+++ b/arch/arm/boot/dts/zynq-7000.dtsi
@@ -28,6 +28,12 @@
 			i-cache-line-size = <0x20>;
 			d-cache-size = <0x8000>;
 			d-cache-line-size = <0x20>;
+			operating-points = <
+				/* kHz    uV */
+				666667  1000000
+				333334  1000000
+				111112  1000000
+			>;
 		};
 
 		cpu at 1 {
diff --git a/arch/arm/mach-zynq/Kconfig b/arch/arm/mach-zynq/Kconfig
index 04f8a4a6e755..8b943f19107d 100644
--- a/arch/arm/mach-zynq/Kconfig
+++ b/arch/arm/mach-zynq/Kconfig
@@ -2,6 +2,8 @@ config ARCH_ZYNQ
 	bool "Xilinx Zynq ARM Cortex A9 Platform" if ARCH_MULTI_V7
 	select ARM_AMBA
 	select ARM_GIC
+	select ARCH_HAS_CPUFREQ
+	select ARCH_HAS_OPP
 	select COMMON_CLK
 	select CPU_V7
 	select GENERIC_CLOCKEVENTS
diff --git a/arch/arm/mach-zynq/common.c b/arch/arm/mach-zynq/common.c
index 5f252569c689..20b373fe855a 100644
--- a/arch/arm/mach-zynq/common.c
+++ b/arch/arm/mach-zynq/common.c
@@ -50,12 +50,15 @@ static struct of_device_id zynq_of_bus_ids[] __initdata = {
  */
 static void __init zynq_init_machine(void)
 {
+	struct platform_device_info devinfo = { .name = "cpufreq-cpu0", };
+
 	/*
 	 * 64KB way size, 8-way associativity, parity disabled
 	 */
 	l2x0_of_init(0x02060000, 0xF0F0FFFF);
 
 	of_platform_bus_probe(NULL, zynq_of_bus_ids, NULL);
+	platform_device_register_full(&devinfo);
 }
 
 static void __init zynq_timer_init(void)
-- 
1.8.4.2




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