[PATCH v5 09/15] clk: qcom: Add KPSS ACC/GCC driver

Sricharan R
2017-12-19T15:54:54Z

From: Stephen Boyd <sboyd@codeaurora.org>

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@vger.kernel.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
---
drivers/clk/qcom/Kconfig | 8 +++++
drivers/clk/qcom/Makefile | 1 +
drivers/clk/qcom/kpss-xcc.c | 87 +++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 96 insertions(+)
create mode 100644 drivers/clk/qcom/kpss-xcc.c

diff --git a/drivers/clk/qcom/Kconfig b/drivers/clk/qcom/Kconfig
index 6592595..17dcb88 100644
--- a/drivers/clk/qcom/Kconfig
+++ b/drivers/clk/qcom/Kconfig
@@ -214,6 +214,14 @@ 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 b6741b0..7ad2302 100644
--- a/drivers/clk/qcom/Makefile
+++ b/drivers/clk/qcom/Makefile
@@ -37,4 +37,5 @@ obj-$(CONFIG_MSM_MMCC_8996) += mmcc-msm8996.o
obj-$(CONFIG_QCOM_CLK_RPM) += clk-rpm.o
obj-$(CONFIG_QCOM_CLK_SMD_RPM) += clk-smd-rpm.o
obj-$(CONFIG_SPMI_PMIC_CLKDIV) += clk-spmi-pmic-div.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 0000000..f260d8f
--- /dev/null
+++ b/drivers/clk/qcom/kpss-xcc.c
@@ -0,0 +1,87 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2017, The Linux Foundation. All rights reserved.
+
+#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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