--- /dev/null
+From 1909c8bf322e0bbb068d57c370c5b64906a8c5a7 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
+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.
+
+Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
+---
+V2: Rebase on top of clk-next
+ Use ALP as parent clock
+ Improve comments
+ Switch from ioremap_nocache to ioremap
+ Check of_clk_add_provide result for error
+V3: Drop #include <linux/moduleh>
+ Make ILP DT entry part of PMU
+ Describe ILP as subdevice of PMU in Documentation
+V4: Use BCM53573 name as suggested by Jon and Ray. It seems "Northstar"
+ (even if used in some resources) should be used in relation to
+ Cortex-A9 devices only.
+V5: Rename remaining "ns" references to "bcm53573", sorry, I sent V4 too
+ early.
+V6: Drop #include <linux/clk.h>
+ Use "int" as type where it matches usage
+ Add cpu_relax() in the loop
+ Add disable callback
+ Use _hw_ functions for registering struct clk_hw (new API)
+
+ Thanks a lot Stephen!
+---
+ .../bindings/clock/brcm,bcm53573-ilp.txt | 40 ++++++
+ drivers/clk/bcm/Makefile | 1 +
+ drivers/clk/bcm/clk-bcm53573-ilp.c | 157 +++++++++++++++++++++
+ 3 files changed, 198 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 @@
++Broadcom BCM53573 ILP clock
++===========================
++
++This binding uses the common clock binding:
++ Documentation/devicetree/bindings/clock/clock-bindings.txt
++
++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.
++
++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>
++
++Example:
++
++pmu@18012000 {
++ compatible = "simple-bus";
++ ranges = <0x00000000 0x18012000 0x00001000>;
++ #address-cells = <1>;
++ #size-cells = <1>;
++
++ ilp: ilp@0 {
++ compatible = "brcm,bcm53573-ilp";
++ reg = <0 0x1000>;
++ reg-names = "pmu";
++ clocks = <&alp>;
++ #clock-cells = <0>;
++ clock-output-names = "ilp";
++ };
++};
+--- a/drivers/clk/bcm/Makefile
++++ b/drivers/clk/bcm/Makefile
+@@ -8,3 +8,4 @@ obj-$(CONFIG_COMMON_CLK_IPROC) += clk-ns
+ obj-$(CONFIG_ARCH_BCM_CYGNUS) += clk-cygnus.o
+ obj-$(CONFIG_ARCH_BCM_NSP) += clk-nsp.o
+ obj-$(CONFIG_ARCH_BCM_5301X) += clk-nsp.o
++obj-$(CONFIG_ARCH_BCM_53573) += clk-bcm53573-ilp.o
+--- /dev/null
++++ b/drivers/clk/bcm/clk-bcm53573-ilp.c
+@@ -0,0 +1,157 @@
++/*
++ * Copyright (C) 2016 Rafał Miłecki <rafal@milecki.pl>
++ *
++ * This program is free software; you can redistribute it and/or modify
++ * it under the terms of the GNU General Public License version 2 as
++ * published by the Free Software Foundation.
++ */
++
++#include <linux/clk-provider.h>
++#include <linux/err.h>
++#include <linux/io.h>
++#include <linux/of.h>
++#include <linux/of_address.h>
++#include <linux/slab.h>
++
++#define PMU_XTAL_FREQ_RATIO 0x66c
++#define XTAL_ALP_PER_4ILP 0x00001fff
++#define XTAL_CTL_EN 0x80000000
++#define PMU_SLOW_CLK_PERIOD 0x6dc
++
++struct bcm53573_ilp {
++ struct clk_hw hw;
++ void __iomem *pmu;
++};
++
++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);
++
++ return 0;
++}
++
++static void bcm53573_ilp_disable(struct clk_hw *hw)
++{
++ struct bcm53573_ilp *ilp = container_of(hw, struct bcm53573_ilp, hw);
++
++ writel(0, ilp->pmu + PMU_SLOW_CLK_PERIOD);
++ writel(0, ilp->pmu + 0x674);
++}
++
++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;
++ 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);
++
++ /* Read initial value */
++ last_val = readl(pmu + PMU_XTAL_FREQ_RATIO) & XTAL_ALP_PER_4ILP;
++
++ /*
++ * At minimum we should loop for a bit to let hardware do the
++ * measurement. This isn't very accurate however, so for a better
++ * 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;
++
++ if (cur_val != last_val) {
++ /* Got different value, use it */
++ sum += cur_val;
++ num++;
++ loop_num = 0;
++ last_val = cur_val;
++ } else if (++loop_num > 5000) {
++ /* Same value over and over, give up */
++ sum += cur_val;
++ num++;
++ break;
++ }
++
++ cpu_relax();
++ }
++
++ /* Disable measurement to save power */
++ writel(0x0, pmu + PMU_XTAL_FREQ_RATIO);
++
++ avg = sum / num;
++
++ return parent_rate * 4 / avg;
++}
++
++static const struct clk_ops bcm53573_ilp_clk_ops = {
++ .enable = bcm53573_ilp_enable,
++ .disable = bcm53573_ilp_disable,
++ .recalc_rate = bcm53573_ilp_recalc_rate,
++};
++
++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);
++ if (!ilp)
++ return;
++
++ parent_name = of_clk_get_parent_name(np, 0);
++ if (!parent_name) {
++ err = -ENOENT;
++ 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);
++ goto err_free_ilp;
++ }
++
++ init.name = np->name;
++ init.ops = &bcm53573_ilp_clk_ops;
++ init.parent_names = &parent_name;
++ init.num_parents = 1;
++
++ ilp->hw.init = &init;
++ err = clk_hw_register(NULL, &ilp->hw);
++ if (err)
++ goto err_unmap_pmu;
++
++ err = of_clk_add_hw_provider(np, of_clk_hw_simple_get, &ilp->hw);
++ if (err)
++ goto err_clk_hw_unregister;
++
++ return;
++
++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);
++}
++
++/* We need it very early for arch code, before device model gets ready */
++CLK_OF_DECLARE(bcm53573_ilp_clk, "brcm,bcm53573-ilp", bcm53573_ilp_init);
+++ /dev/null
-From 65acc8219d271d29b918ae4d6fe4d520203f25ae 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 V3] clk: bcm: Add driver for Northstar ILP clock
-MIME-Version: 1.0
-Content-Type: text/plain; charset=UTF-8
-Content-Transfer-Encoding: 8bit
-
-This clock is present on cheaper Northstar devices like BCM53573 or
-BCM47189 using Corex-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.
-
-Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
----
-V2: Rebase on top of clk-next
- Use ALP as parent clock
- Improve comments
- Switch from ioremap_nocache to ioremap
- Check of_clk_add_provide result for error
-V3: Drop #include <linux/moduleh>
- Make ILP DT entry part of PMU
- Describe ILP as subdevice of PMU in Documentation
----
- .../devicetree/bindings/clock/brcm,ns-ilp.txt | 40 ++++++
- drivers/clk/bcm/Makefile | 1 +
- drivers/clk/bcm/clk-ns-ilp.c | 146 +++++++++++++++++++++
- 3 files changed, 187 insertions(+)
- create mode 100644 Documentation/devicetree/bindings/clock/brcm,ns-ilp.txt
- create mode 100644 drivers/clk/bcm/clk-ns-ilp.c
-
---- /dev/null
-+++ b/Documentation/devicetree/bindings/clock/brcm,ns-ilp.txt
-@@ -0,0 +1,40 @@
-+Broadcom Northstar ILP clock
-+============================
-+
-+This binding uses the common clock binding:
-+ Documentation/devicetree/bindings/clock/clock-bindings.txt
-+
-+This binding is used for ILP clock (sometimes referred as "slow clock")
-+on Broadcom Northstar devices using Corex-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.
-+
-+Required properties:
-+- compatible: "brcm,ns-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>
-+
-+Example:
-+
-+pmu@18012000 {
-+ compatible = "simple-bus";
-+ ranges = <0x00000000 0x18012000 0x00001000>;
-+ #address-cells = <1>;
-+ #size-cells = <1>;
-+
-+ ilp: ilp@0 {
-+ compatible = "brcm,ns-ilp";
-+ reg = <0 0x1000>;
-+ reg-names = "pmu";
-+ clocks = <&alp>;
-+ #clock-cells = <0>;
-+ clock-output-names = "ilp";
-+ };
-+};
---- a/drivers/clk/bcm/Makefile
-+++ b/drivers/clk/bcm/Makefile
-@@ -8,3 +8,4 @@ obj-$(CONFIG_COMMON_CLK_IPROC) += clk-ns
- obj-$(CONFIG_ARCH_BCM_CYGNUS) += clk-cygnus.o
- obj-$(CONFIG_ARCH_BCM_NSP) += clk-nsp.o
- obj-$(CONFIG_ARCH_BCM_5301X) += clk-nsp.o
-+obj-$(CONFIG_ARCH_BCM_5301X) += clk-ns-ilp.o
---- /dev/null
-+++ b/drivers/clk/bcm/clk-ns-ilp.c
-@@ -0,0 +1,146 @@
-+/*
-+ * Copyright (C) 2016 Rafał Miłecki <rafal@milecki.pl>
-+ *
-+ * This program is free software; you can redistribute it and/or modify
-+ * it under the terms of the GNU General Public License version 2 as
-+ * published by the Free Software Foundation.
-+ */
-+
-+#include <linux/clk.h>
-+#include <linux/clk-provider.h>
-+#include <linux/err.h>
-+#include <linux/io.h>
-+#include <linux/of.h>
-+#include <linux/of_address.h>
-+#include <linux/slab.h>
-+
-+#define PMU_XTAL_FREQ_RATIO 0x66c
-+#define XTAL_ALP_PER_4ILP 0x00001fff
-+#define XTAL_CTL_EN 0x80000000
-+#define PMU_SLOW_CLK_PERIOD 0x6dc
-+
-+struct ns_ilp {
-+ struct clk *clk;
-+ struct clk_hw hw;
-+ void __iomem *pmu;
-+};
-+
-+static int ns_ilp_enable(struct clk_hw *hw)
-+{
-+ struct ns_ilp *ilp = container_of(hw, struct ns_ilp, hw);
-+
-+ writel(0x10199, ilp->pmu + PMU_SLOW_CLK_PERIOD);
-+ writel(0x10000, ilp->pmu + 0x674);
-+
-+ return 0;
-+}
-+
-+static unsigned long ns_ilp_recalc_rate(struct clk_hw *hw,
-+ unsigned long parent_rate)
-+{
-+ struct ns_ilp *ilp = container_of(hw, struct ns_ilp, hw);
-+ void __iomem *pmu = ilp->pmu;
-+ u32 last_val, cur_val;
-+ u32 sum = 0, num = 0, loop_num = 0;
-+ u32 avg;
-+
-+ /* Enable measurement */
-+ writel(XTAL_CTL_EN, pmu + PMU_XTAL_FREQ_RATIO);
-+
-+ /* Read initial value */
-+ last_val = readl(pmu + PMU_XTAL_FREQ_RATIO) & XTAL_ALP_PER_4ILP;
-+
-+ /*
-+ * At minimum we should loop for a bit to let hardware do the
-+ * measurement. This isn't very accurate however, so for a better
-+ * 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;
-+
-+ if (cur_val != last_val) {
-+ /* Got different value, use it */
-+ sum += cur_val;
-+ num++;
-+ loop_num = 0;
-+ last_val = cur_val;
-+ } else if (++loop_num > 5000) {
-+ /* Same value over and over, give up */
-+ sum += cur_val;
-+ num++;
-+ break;
-+ }
-+ }
-+
-+ /* Disable measurement to save power */
-+ writel(0x0, pmu + PMU_XTAL_FREQ_RATIO);
-+
-+ avg = sum / num;
-+
-+ return parent_rate * 4 / avg;
-+}
-+
-+static const struct clk_ops ns_ilp_clk_ops = {
-+ .enable = ns_ilp_enable,
-+ .recalc_rate = ns_ilp_recalc_rate,
-+};
-+
-+static void ns_ilp_init(struct device_node *np)
-+{
-+ struct ns_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);
-+ if (!ilp)
-+ return;
-+
-+ parent_name = of_clk_get_parent_name(np, 0);
-+ if (!parent_name) {
-+ err = -ENOENT;
-+ 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);
-+ goto err_free_ilp;
-+ }
-+
-+ init.name = np->name;
-+ init.ops = &ns_ilp_clk_ops;
-+ init.parent_names = &parent_name;
-+ init.num_parents = 1;
-+
-+ ilp->hw.init = &init;
-+ ilp->clk = clk_register(NULL, &ilp->hw);
-+ if (WARN_ON(IS_ERR(ilp->clk)))
-+ goto err_unmap_pmu;
-+
-+ err = of_clk_add_provider(np, of_clk_src_simple_get, ilp->clk);
-+ if (err)
-+ goto err_clk_unregister;
-+
-+ return;
-+
-+err_clk_unregister:
-+ clk_unregister(ilp->clk);
-+err_unmap_pmu:
-+ iounmap(ilp->pmu);
-+err_free_ilp:
-+ kfree(ilp);
-+ pr_err("Failed to init ILP clock: %d\n", err);
-+}
-+CLK_OF_DECLARE(ns_ilp_clk, "brcm,ns-ilp", ns_ilp_init);
projects / openwrt / openwrt.git / commitdiff