[PATCH v3 10/13] clk: qcom: Add KPSS ACC/GCC driver
Stephen Boyd
sboyd at codeaurora.org
Fri Mar 20 23:45:29 PDT 2015
The ACC and GCC regions present in KPSSv1 contain registers to
control clocks and power to each Krait CPU and L2. For CPUfreq
purposes probe these devices and expose a mux clock that chooses
between PXO and PLL8.
Cc: <devicetree at vger.kernel.org>
Signed-off-by: Stephen Boyd <sboyd at codeaurora.org>
---
.../devicetree/bindings/arm/msm/qcom,kpss-acc.txt | 7 ++
.../devicetree/bindings/arm/msm/qcom,kpss-gcc.txt | 28 +++++++
drivers/clk/qcom/Kconfig | 8 ++
drivers/clk/qcom/Makefile | 1 +
drivers/clk/qcom/kpss-xcc.c | 95 ++++++++++++++++++++++
5 files changed, 139 insertions(+)
create mode 100644 Documentation/devicetree/bindings/arm/msm/qcom,kpss-gcc.txt
create mode 100644 drivers/clk/qcom/kpss-xcc.c
diff --git a/Documentation/devicetree/bindings/arm/msm/qcom,kpss-acc.txt b/Documentation/devicetree/bindings/arm/msm/qcom,kpss-acc.txt
index 1333db9acfee..382a574a5c55 100644
--- a/Documentation/devicetree/bindings/arm/msm/qcom,kpss-acc.txt
+++ b/Documentation/devicetree/bindings/arm/msm/qcom,kpss-acc.txt
@@ -21,10 +21,17 @@ PROPERTIES
the register region. An optional second element specifies
the base address and size of the alias register region.
+- clock-output-names:
+ Usage: optional
+ Value type: <string>
+ Definition: Name of the output clock. Typically acpuX_aux where X is a
+ CPU number starting at 0.
+
Example:
clock-controller at 2088000 {
compatible = "qcom,kpss-acc-v2";
reg = <0x02088000 0x1000>,
<0x02008000 0x1000>;
+ clock-output-names = "acpu0_aux";
};
diff --git a/Documentation/devicetree/bindings/arm/msm/qcom,kpss-gcc.txt b/Documentation/devicetree/bindings/arm/msm/qcom,kpss-gcc.txt
new file mode 100644
index 000000000000..d1e12f16a28c
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/msm/qcom,kpss-gcc.txt
@@ -0,0 +1,28 @@
+Krait Processor Sub-system (KPSS) Global Clock Controller (GCC)
+
+PROPERTIES
+
+- compatible:
+ Usage: required
+ Value type: <string>
+ Definition: should be one of:
+ "qcom,kpss-gcc"
+
+- reg:
+ Usage: required
+ Value type: <prop-encoded-array>
+ Definition: base address and size of the register region
+
+- clock-output-names:
+ Usage: required
+ Value type: <string>
+ Definition: Name of the output clock. Typically acpu_l2_aux indicating
+ an L2 cache auxiliary clock.
+
+Example:
+
+ l2cc: clock-controller at 2011000 {
+ compatible = "qcom,kpss-gcc";
+ reg = <0x2011000 0x1000>;
+ clock-output-names = "acpu_l2_aux";
+ };
diff --git a/drivers/clk/qcom/Kconfig b/drivers/clk/qcom/Kconfig
index 7b82b3c4e259..92eb883533d5 100644
--- a/drivers/clk/qcom/Kconfig
+++ b/drivers/clk/qcom/Kconfig
@@ -97,6 +97,14 @@ config QCOM_HFPLL
Say Y if you want to support CPU frequency scaling on devices
such as MSM8974, APQ8084, etc.
+config KPSS_XCC
+ tristate "KPSS Clock Controller"
+ depends on COMMON_CLK_QCOM
+ help
+ Support for the Krait ACC and GCC clock controllers. Say Y
+ if you want to support CPU frequency scaling on devices such
+ as MSM8960, APQ8064, etc.
+
config KRAIT_CLOCKS
bool
select KRAIT_L2_ACCESSORS
diff --git a/drivers/clk/qcom/Makefile b/drivers/clk/qcom/Makefile
index f8d7cfaee4a2..6327dd623773 100644
--- a/drivers/clk/qcom/Makefile
+++ b/drivers/clk/qcom/Makefile
@@ -22,4 +22,5 @@ obj-$(CONFIG_MSM_LCC_8960) += lcc-msm8960.o
obj-$(CONFIG_MSM_GCC_8974) += gcc-msm8974.o
obj-$(CONFIG_MSM_MMCC_8960) += mmcc-msm8960.o
obj-$(CONFIG_MSM_MMCC_8974) += mmcc-msm8974.o
+obj-$(CONFIG_KPSS_XCC) += kpss-xcc.o
obj-$(CONFIG_QCOM_HFPLL) += hfpll.o
diff --git a/drivers/clk/qcom/kpss-xcc.c b/drivers/clk/qcom/kpss-xcc.c
new file mode 100644
index 000000000000..abf6bfd053c1
--- /dev/null
+++ b/drivers/clk/qcom/kpss-xcc.c
@@ -0,0 +1,95 @@
+/* Copyright (c) 2014-2015, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+
+static const char *aux_parents[] = {
+ "pll8_vote",
+ "pxo",
+};
+
+static unsigned int aux_parent_map[] = {
+ 3,
+ 0,
+};
+
+static const struct of_device_id kpss_xcc_match_table[] = {
+ { .compatible = "qcom,kpss-acc-v1", .data = (void *)1UL },
+ { .compatible = "qcom,kpss-gcc" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, kpss_xcc_match_table);
+
+static int kpss_xcc_driver_probe(struct platform_device *pdev)
+{
+ const struct of_device_id *id;
+ struct clk *clk;
+ struct resource *res;
+ void __iomem *base;
+ const char *name;
+
+ id = of_match_device(kpss_xcc_match_table, &pdev->dev);
+ if (!id)
+ return -ENODEV;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ if (id->data) {
+ if (of_property_read_string_index(pdev->dev.of_node,
+ "clock-output-names", 0, &name))
+ return -ENODEV;
+ base += 0x14;
+ } else {
+ name = "acpu_l2_aux";
+ base += 0x28;
+ }
+
+ clk = clk_register_mux_table(&pdev->dev, name, aux_parents,
+ ARRAY_SIZE(aux_parents), 0, base, 0, 0x3,
+ 0, aux_parent_map, NULL);
+
+ platform_set_drvdata(pdev, clk);
+
+ return PTR_ERR_OR_ZERO(clk);
+}
+
+static int kpss_xcc_driver_remove(struct platform_device *pdev)
+{
+ clk_unregister_mux(platform_get_drvdata(pdev));
+ return 0;
+}
+
+static struct platform_driver kpss_xcc_driver = {
+ .probe = kpss_xcc_driver_probe,
+ .remove = kpss_xcc_driver_remove,
+ .driver = {
+ .name = "kpss-xcc",
+ .of_match_table = kpss_xcc_match_table,
+ },
+};
+module_platform_driver(kpss_xcc_driver);
+
+MODULE_DESCRIPTION("Krait Processor Sub System (KPSS) Clock Driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:kpss-xcc");
--
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