-From 1909c8bf322e0bbb068d57c370c5b64906a8c5a7 Mon Sep 17 00:00:00 2001
+From 205fc550ceb74f7e8bfcba5c5c7329aa1b34d4ee Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <rafal@milecki.pl>
Date: Fri, 29 Jul 2016 14:48:19 +0200
-Subject: [PATCH V6] clk: bcm: Add driver for BCM53573 ILP clock
+Subject: [PATCH V8] clk: bcm: Add driver for BCM53573 ILP clock
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
This clock is present on BCM53573 devices (including BCM47189) that use
-Cortex-A7. ILP is a part of PMU (Power Management Unit) and so it should
-be defined as one of its subnodes (subdevices). For more details see
-Documentation entry.
-
-Unfortunately there isn't a set of registers related to ILP clock only.
-We use registers 0x66c, 0x674 and 0x6dc and between them there are e.g.
-"retention*" and "control_ext" regs. This is why this driver maps all
-0x1000 B of space.
+Cortex-A7. ILP is a part of PMU (Power Management Unit) multi-function
+device so we use syscon (and regmap) for it.
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
---
Use _hw_ functions for registering struct clk_hw (new API)
Thanks a lot Stephen!
+V7: Use syscon and regmap (thanks Rob!)
+V8: Update Documentation (drop unused "reg", unit address)
---
- .../bindings/clock/brcm,bcm53573-ilp.txt | 40 ++++++
+ .../bindings/clock/brcm,bcm53573-ilp.txt | 36 +++++
drivers/clk/bcm/Makefile | 1 +
- drivers/clk/bcm/clk-bcm53573-ilp.c | 157 +++++++++++++++++++++
- 3 files changed, 198 insertions(+)
+ drivers/clk/bcm/clk-bcm53573-ilp.c | 148 +++++++++++++++++++++
+ 3 files changed, 185 insertions(+)
create mode 100644 Documentation/devicetree/bindings/clock/brcm,bcm53573-ilp.txt
create mode 100644 drivers/clk/bcm/clk-bcm53573-ilp.c
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/brcm,bcm53573-ilp.txt
-@@ -0,0 +1,40 @@
+@@ -0,0 +1,36 @@
+Broadcom BCM53573 ILP clock
+===========================
+
+This binding is used for ILP clock (sometimes referred as "slow clock")
+on Broadcom BCM53573 devices using Cortex-A7 CPU.
+
-+This clock is part of PMU (Power Management Unit), a Broadcom's device
-+handing power-related aspects. Please note PMU contains more subdevices,
-+ILP is only one of them.
-+
+ILP's rate has to be calculated on runtime and it depends on ALP clock
+which has to be referenced.
+
++This clock is part of PMU (Power Management Unit), a Broadcom's device
++handing power-related aspects. Its node must be sub-node of the PMU
++device.
++
+Required properties:
+- compatible: "brcm,bcm53573-ilp"
-+- reg: iomem address range of PMU (Power Management Unit)
-+- reg-names: "pmu", the only needed & supported reg right now
+- clocks: has to reference an ALP clock
+- #clock-cells: should be <0>
++- clock-output-names: from common clock bindings, should contain clock
++ name
+
+Example:
+
+pmu@18012000 {
-+ compatible = "simple-bus";
-+ ranges = <0x00000000 0x18012000 0x00001000>;
-+ #address-cells = <1>;
-+ #size-cells = <1>;
++ compatible = "simple-mfd", "syscon";
++ reg = <0x18012000 0x00001000>;
+
-+ ilp: ilp@0 {
++ ilp {
+ compatible = "brcm,bcm53573-ilp";
-+ reg = <0 0x1000>;
-+ reg-names = "pmu";
+ clocks = <&alp>;
+ #clock-cells = <0>;
+ clock-output-names = "ilp";
+obj-$(CONFIG_ARCH_BCM_53573) += clk-bcm53573-ilp.o
--- /dev/null
+++ b/drivers/clk/bcm/clk-bcm53573-ilp.c
-@@ -0,0 +1,157 @@
+@@ -0,0 +1,148 @@
+/*
+ * Copyright (C) 2016 Rafał Miłecki <rafal@milecki.pl>
+ *
+#include <linux/clk-provider.h>
+#include <linux/err.h>
+#include <linux/io.h>
++#include <linux/mfd/syscon.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
++#include <linux/regmap.h>
+#include <linux/slab.h>
+
+#define PMU_XTAL_FREQ_RATIO 0x66c
+
+struct bcm53573_ilp {
+ struct clk_hw hw;
-+ void __iomem *pmu;
++ struct regmap *regmap;
+};
+
+static int bcm53573_ilp_enable(struct clk_hw *hw)
+{
+ struct bcm53573_ilp *ilp = container_of(hw, struct bcm53573_ilp, hw);
+
-+ writel(0x10199, ilp->pmu + PMU_SLOW_CLK_PERIOD);
-+ writel(0x10000, ilp->pmu + 0x674);
++ regmap_write(ilp->regmap, PMU_SLOW_CLK_PERIOD, 0x10199);
++ regmap_write(ilp->regmap, 0x674, 0x10000);
+
+ return 0;
+}
+{
+ struct bcm53573_ilp *ilp = container_of(hw, struct bcm53573_ilp, hw);
+
-+ writel(0, ilp->pmu + PMU_SLOW_CLK_PERIOD);
-+ writel(0, ilp->pmu + 0x674);
++ regmap_write(ilp->regmap, PMU_SLOW_CLK_PERIOD, 0);
++ regmap_write(ilp->regmap, 0x674, 0);
+}
+
+static unsigned long bcm53573_ilp_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ struct bcm53573_ilp *ilp = container_of(hw, struct bcm53573_ilp, hw);
-+ void __iomem *pmu = ilp->pmu;
++ struct regmap *regmap = ilp->regmap;
+ u32 last_val, cur_val;
+ int sum = 0, num = 0, loop_num = 0;
+ int avg;
+
+ /* Enable measurement */
-+ writel(XTAL_CTL_EN, pmu + PMU_XTAL_FREQ_RATIO);
++ regmap_write(regmap, PMU_XTAL_FREQ_RATIO, XTAL_CTL_EN);
+
+ /* Read initial value */
-+ last_val = readl(pmu + PMU_XTAL_FREQ_RATIO) & XTAL_ALP_PER_4ILP;
++ regmap_read(regmap, PMU_XTAL_FREQ_RATIO, &last_val);
++ last_val &= XTAL_ALP_PER_4ILP;
+
+ /*
+ * At minimum we should loop for a bit to let hardware do the
+ * precision lets try getting 20 different values for and use average.
+ */
+ while (num < 20) {
-+ cur_val = readl(pmu + PMU_XTAL_FREQ_RATIO) & XTAL_ALP_PER_4ILP;
++ regmap_read(regmap, PMU_XTAL_FREQ_RATIO, &cur_val);
++ cur_val &= XTAL_ALP_PER_4ILP;
+
+ if (cur_val != last_val) {
+ /* Got different value, use it */
+ }
+
+ /* Disable measurement to save power */
-+ writel(0x0, pmu + PMU_XTAL_FREQ_RATIO);
++ regmap_write(regmap, PMU_XTAL_FREQ_RATIO, 0x0);
+
+ avg = sum / num;
+
+static void bcm53573_ilp_init(struct device_node *np)
+{
+ struct bcm53573_ilp *ilp;
-+ struct resource res;
+ struct clk_init_data init = { 0 };
+ const char *parent_name;
-+ int index;
+ int err;
+
+ ilp = kzalloc(sizeof(*ilp), GFP_KERNEL);
+ goto err_free_ilp;
+ }
+
-+ /* TODO: This looks generic, try making it OF helper. */
-+ index = of_property_match_string(np, "reg-names", "pmu");
-+ if (index < 0) {
-+ err = index;
-+ goto err_free_ilp;
-+ }
-+ err = of_address_to_resource(np, index, &res);
-+ if (err)
-+ goto err_free_ilp;
-+ ilp->pmu = ioremap(res.start, resource_size(&res));
-+ if (IS_ERR(ilp->pmu)) {
-+ err = PTR_ERR(ilp->pmu);
++ ilp->regmap = syscon_node_to_regmap(of_get_parent(np));
++ if (IS_ERR(ilp->regmap)) {
++ err = PTR_ERR(ilp->regmap);
+ goto err_free_ilp;
+ }
+
+ ilp->hw.init = &init;
+ err = clk_hw_register(NULL, &ilp->hw);
+ if (err)
-+ goto err_unmap_pmu;
++ goto err_free_ilp;
+
+ err = of_clk_add_hw_provider(np, of_clk_hw_simple_get, &ilp->hw);
+ if (err)
+
+err_clk_hw_unregister:
+ clk_hw_unregister(&ilp->hw);
-+err_unmap_pmu:
-+ iounmap(ilp->pmu);
+err_free_ilp:
+ kfree(ilp);
+ pr_err("Failed to init ILP clock: %d\n", err);
projects / openwrt / staging / rmilecki.git / commitdiff