[PATCH v9 4/7] clk: qcom: Add A53 PLL support

From: Georgi Djakov
Date: Thu Sep 21 2017 - 12:51:40 EST


The CPUs on Qualcomm MSM8916-based platforms are clocked by two PLLs,
a primary (A53) CPU PLL and a secondary fixed-rate GPLL0. These sources
are connected to a mux and half-integer divider, which is feeding the
CPU cores.

This patch adds support for the primary CPU PLL which generates the
higher range of frequencies above 1GHz.

Signed-off-by: Georgi Djakov <georgi.djakov@xxxxxxxxxx>
---
.../devicetree/bindings/clock/qcom,a53pll.txt | 22 +++++
drivers/clk/qcom/Kconfig | 10 ++
drivers/clk/qcom/Makefile | 1 +
drivers/clk/qcom/a53-pll.c | 107 +++++++++++++++++++++
4 files changed, 140 insertions(+)
create mode 100644 Documentation/devicetree/bindings/clock/qcom,a53pll.txt
create mode 100644 drivers/clk/qcom/a53-pll.c

diff --git a/Documentation/devicetree/bindings/clock/qcom,a53pll.txt b/Documentation/devicetree/bindings/clock/qcom,a53pll.txt
new file mode 100644
index 000000000000..e3fa8118eaee
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/qcom,a53pll.txt
@@ -0,0 +1,22 @@
+Qualcomm MSM8916 A53 PLL Binding
+--------------------------------
+The A53 PLL on MSM8916 platforms is the main CPU PLL used used for frequencies
+above 1GHz.
+
+Required properties :
+- compatible : Shall contain only one of the following:
+
+ "qcom,msm8916-a53pll"
+
+- reg : shall contain base register location and length
+
+- #clock-cells : must be set to <0>
+
+Example:
+
+ a53pll: clock@b016000 {
+ compatible = "qcom,msm8916-a53pll";
+ reg = <0xb016000 0x40>;
+ #clock-cells = <0>;
+ };
+
diff --git a/drivers/clk/qcom/Kconfig b/drivers/clk/qcom/Kconfig
index 9f6c278deead..81ac7b9378fe 100644
--- a/drivers/clk/qcom/Kconfig
+++ b/drivers/clk/qcom/Kconfig
@@ -12,6 +12,16 @@ config COMMON_CLK_QCOM
select REGMAP_MMIO
select RESET_CONTROLLER

+config QCOM_A53PLL
+ bool "MSM8916 A53 PLL"
+ depends on COMMON_CLK_QCOM
+ default ARCH_QCOM
+ help
+ Support for the A53 PLL on MSM8916 devices. It provides
+ the CPU with frequencies above 1GHz.
+ Say Y if you want to support higher CPU frequencies on MSM8916
+ devices.
+
config QCOM_CLK_RPM
tristate "RPM based Clock Controller"
depends on COMMON_CLK_QCOM && MFD_QCOM_RPM
diff --git a/drivers/clk/qcom/Makefile b/drivers/clk/qcom/Makefile
index 3f3aff229fb7..19ae884b5166 100644
--- a/drivers/clk/qcom/Makefile
+++ b/drivers/clk/qcom/Makefile
@@ -31,5 +31,6 @@ obj-$(CONFIG_MSM_LCC_8960) += lcc-msm8960.o
obj-$(CONFIG_MSM_MMCC_8960) += mmcc-msm8960.o
obj-$(CONFIG_MSM_MMCC_8974) += mmcc-msm8974.o
obj-$(CONFIG_MSM_MMCC_8996) += mmcc-msm8996.o
+obj-$(CONFIG_QCOM_A53PLL) += a53-pll.o
obj-$(CONFIG_QCOM_CLK_RPM) += clk-rpm.o
obj-$(CONFIG_QCOM_CLK_SMD_RPM) += clk-smd-rpm.o
diff --git a/drivers/clk/qcom/a53-pll.c b/drivers/clk/qcom/a53-pll.c
new file mode 100644
index 000000000000..6276934daa0a
--- /dev/null
+++ b/drivers/clk/qcom/a53-pll.c
@@ -0,0 +1,107 @@
+/*
+ * Copyright (c) 2017, Linaro Limited
+ * Copyright (c) 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/clk-provider.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#include "clk-pll.h"
+#include "clk-regmap.h"
+
+static const struct pll_freq_tbl a53pll_freq[] = {
+ { 998400000, 52, 0x0, 0x1, 0 },
+ { 1094400000, 57, 0x0, 0x1, 0 },
+ { 1152000000, 62, 0x0, 0x1, 0 },
+ { 1209600000, 65, 0x0, 0x1, 0 },
+ { 1401600000, 73, 0x0, 0x1, 0 },
+};
+
+static const struct regmap_config a53pll_regmap_config = {
+ .reg_bits = 32,
+ .reg_stride = 4,
+ .val_bits = 32,
+ .max_register = 0x40,
+ .fast_io = true,
+};
+
+static const struct of_device_id qcom_a53pll_match_table[] = {
+ { .compatible = "qcom,msm8916-a53pll" },
+ { }
+};
+
+static int qcom_a53pll_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct regmap *regmap;
+ struct resource *res;
+ struct clk_pll *pll;
+ void __iomem *base;
+ struct clk_init_data init = { };
+ int ret;
+
+ pll = devm_kzalloc(dev, sizeof(*pll), GFP_KERNEL);
+ if (!pll)
+ 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(dev, base, &a53pll_regmap_config);
+ if (IS_ERR(regmap))
+ return PTR_ERR(regmap);
+
+ pll->l_reg = 0x04;
+ pll->m_reg = 0x08;
+ pll->n_reg = 0x0c;
+ pll->config_reg = 0x14;
+ pll->mode_reg = 0x00;
+ pll->status_reg = 0x1c;
+ pll->status_bit = 16;
+ pll->freq_tbl = a53pll_freq;
+
+ init.name = "a53pll";
+ init.parent_names = (const char *[]){ "xo" };
+ init.num_parents = 1;
+ init.ops = &clk_pll_sr2_ops;
+ init.flags = CLK_IS_CRITICAL;
+ pll->clkr.hw.init = &init;
+
+ ret = devm_clk_register_regmap(dev, &pll->clkr);
+ if (ret) {
+ dev_err(dev, "failed to register regmap clock: %d\n", ret);
+ return ret;
+ }
+
+ ret = of_clk_add_hw_provider(dev->of_node, of_clk_hw_simple_get,
+ &pll->clkr.hw);
+ if (ret) {
+ dev_err(dev, "failed to add clock provider: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static struct platform_driver qcom_a53pll_driver = {
+ .probe = qcom_a53pll_probe,
+ .driver = {
+ .name = "qcom-a53pll",
+ .of_match_table = qcom_a53pll_match_table,
+ },
+};
+
+builtin_platform_driver(qcom_a53pll_driver);