Re: [PATCH linux-next (v2) 2/2] clk: bcm6345: Add BCM6345 gated clock support
Hi Simon,
Quoting Simon Arlott (2015-12-10 13:50:59)
> +#define to_clk_bcm6345(_hw) container_of(_hw, struct clk_bcm6345, hw)
> +
> +static int clk_bcm6345_enable(struct clk_hw *hw)
> +{
> + struct clk_bcm6345 *gate = to_clk_bcm6345(hw);
> +
> + return regmap_write_bits(gate->map, gate->offset,
> + gate->mask, gate->mask);
Does your regmap hold a spinlock or mutex? If a mutex then this should
be a .prepare callback instead of .enable. If it's a spinlock then
nothing to see here, move along.
> +}
> +
> +static void clk_bcm6345_disable(struct clk_hw *hw)
> +{
> + struct clk_bcm6345 *gate = to_clk_bcm6345(hw);
> +
> + regmap_write_bits(gate->map, gate->offset,
> + gate->mask, 0);
> +}
> +
> +static int clk_bcm6345_is_enabled(struct clk_hw *hw)
> +{
> + struct clk_bcm6345 *gate = to_clk_bcm6345(hw);
> + unsigned int val;
> + int ret;
> +
> + ret = regmap_read(gate->map, gate->offset, &val);
> + if (ret)
> + return ret;
> +
> + val &= gate->mask;
> +
> + return val ? 1 : 0;
> +}
> +
> +const struct clk_ops clk_bcm6345_ops = {
> + .enable = clk_bcm6345_enable,
> + .disable = clk_bcm6345_disable,
> + .is_enabled = clk_bcm6345_is_enabled,
> +};
> +
> +static struct clk * __init of_bcm6345_clk_register(const char *parent_name,
> + const char *clk_name, struct regmap *map, u32 offset, u32 mask)
> +{
> + struct clk_bcm6345 *gate;
> + struct clk_init_data init;
> + struct clk *ret;
> +
> + gate = kzalloc(sizeof(*gate), GFP_KERNEL);
> + if (!gate)
> + return ERR_PTR(-ENOMEM);
> +
> + init.name = clk_name;
> + init.ops = &clk_bcm6345_ops;
> + init.flags = CLK_IS_BASIC;
Why is CLK_IS_BASIC set?
> + init.parent_names = (parent_name ? &parent_name : NULL);
> + init.num_parents = (parent_name ? 1 : 0);
> + gate->hw.init = &init;
> + gate->map = map;
> + gate->offset = offset;
> + gate->mask = mask;
> +
> + ret = clk_register(NULL, &gate->hw);
> + if (IS_ERR(ret))
> + kfree(gate);
> +
> + return ret;
> +}
> +
> +static void __init of_bcm6345_clk_setup(struct device_node *node)
> +{
> + struct clk_onecell_data *clk_data;
> + const char *parent_name = NULL;
> + struct regmap *map;
> + u32 offset;
> + unsigned int clocks = 0;
> + int i;
> +
> + clk_data = kzalloc(sizeof(*clk_data), GFP_KERNEL);
> + if (!clk_data)
> + return;
> +
> + clk_data->clk_num = 32;
> + clk_data->clks = kmalloc_array(clk_data->clk_num,
> + sizeof(*clk_data->clks), GFP_KERNEL);
> +
> + for (i = 0; i < clk_data->clk_num; i++)
> + clk_data->clks[i] = ERR_PTR(-ENODEV);
> +
> + if (of_clk_get_parent_count(node) > 0)
> + parent_name = of_clk_get_parent_name(node, 0);
> +
> + map = syscon_regmap_lookup_by_phandle(node, "regmap");
> + if (IS_ERR(map)) {
> + pr_err("%s: regmap lookup error %ld\n",
> + node->full_name, PTR_ERR(map));
> + goto out;
> + }
> +
> + if (of_property_read_u32(node, "offset", &offset)) {
> + pr_err("%s: offset not specified\n", node->full_name);
> + goto out;
> + }
> +
> + /* clks[] is sparse, indexed by bit, maximum clocks checked using i */
> + for (i = 0; i < clk_data->clk_num; i++) {
> + u32 bit;
> + const char *clk_name;
> +
> + if (of_property_read_u32_index(node, "clock-indices",
> + i, &bit))
> + goto out;
> +
> + if (of_property_read_string_index(node, "clock-output-names",
> + i, &clk_name))
> + goto out;
> +
> + if (bit >= clk_data->clk_num) {
> + pr_err("%s: clock bit %u out of range\n",
> + node->full_name, bit);
> + continue;
> + }
> +
> + if (!IS_ERR(clk_data->clks[bit])) {
> + pr_err("%s: clock bit %u already exists\n",
> + node->full_name, bit);
> + continue;
> + }
> +
> + clk_data->clks[bit] = of_bcm6345_clk_register(parent_name,
> + clk_name, map, offset, BIT(bit));
> + if (!IS_ERR(clk_data->clks[bit]))
> + clocks++;
> + }
> +
> +out:
> + if (clocks) {
> + of_clk_add_provider(node, of_clk_src_onecell_get, clk_data);
> + pr_info("%s: registered %u clocks\n", node->name, clocks);
> + } else {
> + kfree(clk_data->clks);
> + kfree(clk_data);
> + }
>
[PATCH linux-next (v2) 2/2] clk: bcm6345: Add BCM6345 gated clock support
The BCM6345 contains clocks gated with a register. Clocks are indexed
by bits in the register and are active high. Most MIPS-based BCM63xx
SoCs have a clock gating set of registers, but some have clock gate bits
interleaved with other status bits and configurable clocks in the same
register.
Enabled by default for BMIPS_GENERIC.
Signed-off-by: Simon Arlott
---
v2: Resend, no changes.
v1: Renamed from BCM63xx to BCM6345.
MAINTAINERS | 1 +
drivers/clk/bcm/Kconfig | 9 ++
drivers/clk/bcm/Makefile | 1 +
drivers/clk/bcm/clk-bcm6345.c | 191 ++
4 files changed, 202 insertions(+)
create mode 100644 drivers/clk/bcm/clk-bcm6345.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 5ac17b0..9b54ddc 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2389,6 +2389,7 @@ F:arch/mips/bmips/*
F: arch/mips/include/asm/mach-bmips/*
F: arch/mips/kernel/*bmips*
F: arch/mips/boot/dts/brcm/bcm*.dts*
+F: drivers/clk/bcm/clk-bcm6345*
F: drivers/irqchip/irq-bcm63*
F: drivers/irqchip/irq-bcm7*
F: drivers/irqchip/irq-brcmstb*
diff --git a/drivers/clk/bcm/Kconfig b/drivers/clk/bcm/Kconfig
index f287845..043353a 100644
--- a/drivers/clk/bcm/Kconfig
+++ b/drivers/clk/bcm/Kconfig
@@ -8,6 +8,15 @@ config CLK_BCM_63XX
Enable common clock framework support for Broadcom BCM63xx DSL SoCs
based on the ARM architecture
+config CLK_BCM_6345
+ bool "Broadcom BCM6345 clock support"
+ depends on BMIPS_GENERIC || COMPILE_TEST
+ depends on COMMON_CLK
+ default BMIPS_GENERIC
+ help
+ Enable common clock framework support for Broadcom BCM6345 DSL SoCs
+ based on the MIPS architecture
+
config CLK_BCM_KONA
bool "Broadcom Kona CCU clock support"
depends on ARCH_BCM_MOBILE || COMPILE_TEST
diff --git a/drivers/clk/bcm/Makefile b/drivers/clk/bcm/Makefile
index 247c267..e2bac43 100644
--- a/drivers/clk/bcm/Makefile
+++ b/drivers/clk/bcm/Makefile
@@ -1,4 +1,5 @@
obj-$(CONFIG_CLK_BCM_63XX) += clk-bcm63xx.o
+obj-$(CONFIG_CLK_BCM_6345) += clk-bcm6345.o
obj-$(CONFIG_CLK_BCM_KONA) += clk-kona.o
obj-$(CONFIG_CLK_BCM_KONA) += clk-kona-setup.o
obj-$(CONFIG_CLK_BCM_KONA) += clk-bcm281xx.o
diff --git a/drivers/clk/bcm/clk-bcm6345.c b/drivers/clk/bcm/clk-bcm6345.c
new file mode 100644
index 000..88a1e7e
--- /dev/null
+++ b/drivers/clk/bcm/clk-bcm6345.c
@@ -0,0 +1,191 @@
+/*
+ * Copyright 2015 Simon Arlott
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * Derived from clk-gate.c:
+ * Copyright (C) 2010-2011 Canonical Ltd
+ * Copyright (C) 2011-2012 Mike Turquette, Linaro Ltd
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+#include
+
+/**
+ * DOC: Basic clock which uses a bit in a regmap to gate and ungate the output
+ *
+ * Traits of this clock:
+ * prepare - clk_(un)prepare only ensures parent is (un)prepared
+ * enable - clk_enable and clk_disable are functional & control gating
+ * rate - inherits rate from parent. No clk_set_rate support
+ * parent - fixed parent. No clk_set_parent support
+ */
+
+struct clk_bcm6345 {
+ struct clk_hw hw;
+ struct regmap *map;
+ u32 offset;
+ u32 mask;
+};
+
+#define to_clk_bcm6345(_hw) container_of(_hw, struct clk_bcm6345, hw)
+
+static int clk_bcm6345_enable(struct clk_hw *hw)
+{
+ struct clk_bcm6345 *gate = to_clk_bcm6345(hw);
+
+ return regmap_write_bits(gate->map, gate->offset,
+ gate->mask, gate->mask);
+}
+
+static void clk_bcm6345_disable(struct clk_hw *hw)
+{
+ struct clk_bcm6345 *gate = to_clk_bcm6345(hw);
+
+ regmap_write_bits(gate->map, gate->offset,
+ gate->mask, 0);
+}
+
+static int clk_bcm6345_is_enabled(struct clk_hw *hw)
+{
+ struct clk_bcm6345 *gate = to_clk_bcm6345(hw);
+ unsigned int val;
+ int ret;
+
+ ret = regmap_read(gate->map, gate->offset, &val);
+ if (ret)
+ return ret;
+
+ val &= gate->mask;
+
+ return val ? 1 : 0;
+}
+
+const struct clk_ops clk_bcm6345_ops = {
+ .enable = clk_bcm6345_enable,
+ .disable = clk_bcm6345_disable,
+ .is_enabled = clk_bcm6345_is_enabled,
+};
+
+static struct clk * __init of_bcm6345_clk_register(const char *parent_name,
+ const char *clk_name, struct regmap *map, u32 offset, u32 mask)
+{
+ struct clk_bcm6345 *gate;
+ struct clk_i
