[PATCH v3 06/13] clk: qcom: Add HFPLL driver

[Stephen Boyd]

On some devices (MSM8974 for example), the HFPLLs are
instantiated within the Krait processor subsystem as separate
register regions. Add a driver for these PLLs so that we can
provide HFPLL clocks for use by the system.

Cc: <devicetree at vger.kernel.org>
Signed-off-by: Stephen Boyd <sboyd at codeaurora.org>
---
 .../devicetree/bindings/clock/qcom,hfpll.txt       |  40 ++++++++
 drivers/clk/qcom/Kconfig                           |   8 ++
 drivers/clk/qcom/Makefile                          |   1 +
 drivers/clk/qcom/hfpll.c                           | 109 +++++++++++++++++++++
 4 files changed, 158 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/clock/qcom,hfpll.txt
 create mode 100644 drivers/clk/qcom/hfpll.c

diff --git a/Documentation/devicetree/bindings/clock/qcom,hfpll.txt b/Documentation/devicetree/bindings/clock/qcom,hfpll.txt
new file mode 100644
index 000000000000..fee92bb30344
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/qcom,hfpll.txt
@@ -0,0 +1,40 @@
+High-Frequency PLL (HFPLL)
+
+PROPERTIES
+
+- compatible:
+	Usage: required
+	Value type: <string>
+	Definition: must be "qcom,hfpll"
+
+- reg:
+	Usage: required
+	Value type: <prop-encoded-array>
+	Definition: address and size of HPLL registers. An optional second
+		    element specifies the address and size of the alias
+		    register region.
+
+- clock-output-names:
+	Usage: required
+	Value type: <string>
+	Definition: Name of the PLL. Typically hfpllX where X is a CPU number
+		    starting at 0. Otherwise hfpll_Y where Y is more specific
+		    such as "l2".
+
+Example:
+
+1) An HFPLL for the L2 cache.
+
+	clock-controller at f9016000 {
+		compatible = "qcom,hfpll";
+		reg = <0xf9016000 0x30>;
+		clock-output-names = "hfpll_l2";
+	};
+
+2) An HFPLL for CPU0. This HFPLL has the alias register region.
+
+	clock-controller at f908a000 {
+		compatible = "qcom,hfpll";
+		reg = <0xf908a000 0x30>, <0xf900a000 0x30>;
+		clock-output-names = "hfpll0";
+	};
diff --git a/drivers/clk/qcom/Kconfig b/drivers/clk/qcom/Kconfig
index 0d7ab52b7ab0..d421fd195114 100644
--- a/drivers/clk/qcom/Kconfig
+++ b/drivers/clk/qcom/Kconfig
@@ -88,3 +88,11 @@ config MSM_MMCC_8974
 	  Support for the multimedia clock controller on msm8974 devices.
 	  Say Y if you want to support multimedia devices such as display,
 	  graphics, video encode/decode, camera, etc.
+
+config QCOM_HFPLL
+	tristate "High-Frequency PLL (HFPLL) Clock Controller"
+	depends on COMMON_CLK_QCOM
+	help
+	  Support for the high-frequency PLLs present on Qualcomm devices.
+	  Say Y if you want to support CPU frequency scaling on devices
+	  such as MSM8974, APQ8084, etc.
diff --git a/drivers/clk/qcom/Makefile b/drivers/clk/qcom/Makefile
index 953f792d2133..b1076179fb17 100644
--- a/drivers/clk/qcom/Makefile
+++ b/drivers/clk/qcom/Makefile
@@ -21,3 +21,4 @@ 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_QCOM_HFPLL) += hfpll.o
diff --git a/drivers/clk/qcom/hfpll.c b/drivers/clk/qcom/hfpll.c
new file mode 100644
index 000000000000..0092017b257d
--- /dev/null
+++ b/drivers/clk/qcom/hfpll.c
@@ -0,0 +1,109 @@
+/*
+ * Copyright (c) 2013-2014, 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/of.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/regmap.h>
+
+#include "clk-regmap.h"
+#include "clk-hfpll.h"
+
+static const struct hfpll_data hdata = {
+	.mode_reg = 0x00,
+	.l_reg = 0x04,
+	.m_reg = 0x08,
+	.n_reg = 0x0c,
+	.user_reg = 0x10,
+	.config_reg = 0x14,
+	.config_val = 0x430405d,
+	.status_reg = 0x1c,
+	.lock_bit = 16,
+
+	.user_val = 0x8,
+	.user_vco_mask = 0x100000,
+	.low_vco_max_rate = 1248000000,
+	.min_rate = 537600000UL,
+	.max_rate = 2900000000UL,
+};
+
+static const struct of_device_id qcom_hfpll_match_table[] = {
+	{ .compatible = "qcom,hfpll" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, qcom_hfpll_match_table);
+
+static const struct regmap_config hfpll_regmap_config = {
+	.reg_bits	= 32,
+	.reg_stride	= 4,
+	.val_bits	= 32,
+	.max_register	= 0x30,
+	.fast_io	= true,
+};
+
+static int qcom_hfpll_probe(struct platform_device *pdev)
+{
+	struct clk *clk;
+	struct resource *res;
+	struct device *dev = &pdev->dev;
+	void __iomem *base;
+	struct regmap *regmap;
+	struct clk_hfpll *h;
+	struct clk_init_data init = {
+		.parent_names = (const char *[]){ "xo" },
+		.num_parents = 1,
+		.ops = &clk_ops_hfpll,
+	};
+
+	h = devm_kzalloc(dev, sizeof(*h), GFP_KERNEL);
+	if (!h)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	regmap = devm_regmap_init_mmio(&pdev->dev, base, &hfpll_regmap_config);
+	if (IS_ERR(regmap))
+		return PTR_ERR(regmap);
+
+	if (of_property_read_string_index(dev->of_node, "clock-output-names",
+						  0, &init.name))
+		return -ENODEV;
+
+	h->d = &hdata;
+	h->clkr.hw.init = &init;
+	spin_lock_init(&h->lock);
+
+	clk = devm_clk_register_regmap(&pdev->dev, &h->clkr);
+
+	return PTR_ERR_OR_ZERO(clk);
+}
+
+static struct platform_driver qcom_hfpll_driver = {
+	.probe		= qcom_hfpll_probe,
+	.driver		= {
+		.name	= "qcom-hfpll",
+		.of_match_table = qcom_hfpll_match_table,
+	},
+};
+module_platform_driver(qcom_hfpll_driver);
+
+MODULE_DESCRIPTION("QCOM HFPLL Clock Driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:qcom-hfpll");
-- 
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