[PATCH v3 0/3] clk: Add APM X-Gene SoC clock driver

[PATCH v3 0/3] clk: Add APM X-Gene SoC clock driver

[Loc Ho]

This patch adds APM X-Gene SoC clock driver support. Reference,
PCP PLL, SoC PCP, and Ethernet clocks are defined via the DTS.

-v3:
 * Make DTS compatible type for SoC PLL and PCP PLL
 * Make use of of_iomap instead direct ioremap call
 * Make kzalloc with variable instead structure
 * Remove DTS binding for fixed-clock and fixed_factor_clock
 * Remove unnecessary arch_initcall

-v2:
 * Make depends on ARM64
 * Fix duplicate registration

-v1 - Initial post

Loc Ho (3):
  clk: Add APM X-Gene SoC clock driver for reference, PLL, and device
    clocks.
  clk: arm64: Add DTS clock entry for APM X-Gene Storm SoC with
    reference to
  Documentation: Add documentation for APM X-Gene clock binding with
    PLL and

 Documentation/devicetree/bindings/clock/xgene.txt |   90 ++++
 arch/arm64/boot/dts/apm-storm.dtsi                |   75 +++
 drivers/clk/Kconfig                               |    7 +
 drivers/clk/Makefile                              |    1 +
 drivers/clk/clk-xgene.c                           |  538 +++++++++++++++++++++
 5 files changed, 711 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/clock/xgene.txt
 create mode 100644 drivers/clk/clk-xgene.c

[PATCH v3 1/3] clk: Add APM X-Gene SoC clock driver for reference, PLL, and device clocks.

[Loc Ho]

clk: Add APM X-Gene SoC clock driver for reference, PLL, and device clocks.

Signed-off-by: Loc Ho <lho@apm.com>
Signed-off-by: Kumar Sankaran <ksankaran@apm.com>
Signed-off-by: Vinayak Kale <vkale@apm.com>
Signed-off-by: Feng Kan <fkan@apm.com>
---
 drivers/clk/Kconfig     |    7 +
 drivers/clk/Makefile    |    1 +
 drivers/clk/clk-xgene.c |  538 +++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 546 insertions(+), 0 deletions(-)
 create mode 100644 drivers/clk/clk-xgene.c

diff --git a/drivers/clk/Kconfig b/drivers/clk/Kconfig
index 0357ac4..534a722 100644
--- a/drivers/clk/Kconfig
+++ b/drivers/clk/Kconfig
@@ -81,6 +81,13 @@ config COMMON_CLK_AXI_CLKGEN
 	  Support for the Analog Devices axi-clkgen pcore clock generator for Xilinx
 	  FPGAs. It is commonly used in Analog Devices' reference designs.
 
+config COMMON_CLK_XGENE
+	bool "Clock driver for APM XGene SoC"
+	default y
+	depends on ARM64
+	---help---
+	  Sypport for the APM X-Gene SoC reference, PLL, and device clocks.
+
 endmenu
 
 source "drivers/clk/mvebu/Kconfig"
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index 137d3e7..4c96337 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -39,3 +39,4 @@ obj-$(CONFIG_COMMON_CLK_WM831X) += clk-wm831x.o
 obj-$(CONFIG_COMMON_CLK_MAX77686) += clk-max77686.o
 obj-$(CONFIG_COMMON_CLK_SI5351) += clk-si5351.o
 obj-$(CONFIG_CLK_TWL6040)	+= clk-twl6040.o
+obj-$(CONFIG_COMMON_CLK_XGENE)  += clk-xgene.o
diff --git a/drivers/clk/clk-xgene.c b/drivers/clk/clk-xgene.c
new file mode 100644
index 0000000..4f5aa6c
--- /dev/null
+++ b/drivers/clk/clk-xgene.c
@@ -0,0 +1,538 @@
+/*
+ * clk-xgene.c - AppliedMicro X-Gene Clock Interface
+ *
+ * Copyright (c) 2013, Applied Micro Circuits Corporation
+ * Author: Loc Ho <lho@apm.com>
+ *
+ * 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; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ *
+ */
+#include <linux/module.h>
+#include <linux/spinlock.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
+#include <linux/of_address.h>
+#include <asm/setup.h>
+
+/* Register SCU_PCPPLL bit fields */
+#define N_DIV_RD(src)			(((src) & 0x000001ff))
+
+/* Register SCU_SOCPLL bit fields */
+#define CLKR_RD(src)			(((src) & 0x07000000)>>24)
+#define CLKOD_RD(src)			(((src) & 0x00300000)>>20)
+#define REGSPEC_RESET_F1_MASK		0x00010000
+#define CLKF_RD(src)			(((src) & 0x000001ff))
+
+#define XGENE_CLK_DRIVER_VER		"0.1"
+
+static DEFINE_SPINLOCK(clk_lock);
+
+static inline u32 xgene_clk_read(void *csr)
+{
+	return readl_relaxed(csr);
+}
+
+static inline void xgene_clk_write(u32 data, void *csr)
+{
+	return writel_relaxed(data, csr);
+}
+
+/* PLL Clock */
+enum xgene_pll_type {
+	PLL_TYPE_PCP = 0,
+	PLL_TYPE_SOC = 1,
+};
+
+struct xgene_clk_pll {
+	struct clk_hw	hw;
+	const char	*name;
+	void __iomem	*reg;
+	spinlock_t	*lock;
+	u32		pll_offset;
+	enum xgene_pll_type	type;
+};
+
+#define to_xgene_clk_pll(_hw) container_of(_hw, struct xgene_clk_pll, hw)
+
+static int xgene_clk_pll_is_enabled(struct clk_hw *hw)
+{
+	struct xgene_clk_pll *pllclk = to_xgene_clk_pll(hw);
+	u32 data;
+
+	data = xgene_clk_read(pllclk->reg + pllclk->pll_offset);
+	pr_debug("%s pll %s\n", pllclk->name,
+		data & REGSPEC_RESET_F1_MASK ? "disabled" : "enabled");
+
+	return data & REGSPEC_RESET_F1_MASK ? 0 : 1;
+}
+
+static unsigned long xgene_clk_pll_recalc_rate(struct clk_hw *hw,
+				unsigned long parent_rate)
+{
+	struct xgene_clk_pll *pllclk = to_xgene_clk_pll(hw);
+	unsigned long fref;
+	unsigned long fvco;
+	u32 pll;
+	u32 nref;
+	u32 nout;
+	u32 nfb;
+
+	pll = xgene_clk_read(pllclk->reg + pllclk->pll_offset);
+
+	if (pllclk->type == PLL_TYPE_PCP) {
+		/*
+		 * PLL VCO = Reference clock * NF
+		 * PCP PLL = PLL_VCO / 2
+		 */
+		nout = 2;
+		fvco = parent_rate * (N_DIV_RD(pll) + 4);
+	} else {
+		/*
+		 * Fref = Reference Clock / NREF;
+		 * Fvco = Fref * NFB;
+		 * Fout = Fvco / NOUT;
+		 */
+		nref = CLKR_RD(pll) + 1;
+		nout = CLKOD_RD(pll) + 1;
+		nfb = CLKF_RD(pll);
+		fref = parent_rate / nref;
+		fvco = fref * nfb;
+	}
+	pr_debug("%s pll recalc rate %ld parent %ld\n", pllclk->name,
+		fvco / nout, parent_rate);
+
+	return fvco / nout;
+}
+
+const struct clk_ops xgene_clk_pll_ops = {
+	.is_enabled = xgene_clk_pll_is_enabled,
+	.recalc_rate = xgene_clk_pll_recalc_rate,
+};
+
+static struct clk *xgene_register_clk_pll(struct device *dev,
+	const char *name, const char *parent_name,
+	unsigned long flags, void __iomem *reg, u32 pll_offset,
+	u32 type, spinlock_t *lock)
+{
+	struct xgene_clk_pll *apmclk;
+	struct clk *clk;
+	struct clk_init_data init;
+
+	/* allocate the APM clock structure */
+	apmclk = kzalloc(sizeof(*apmclk), GFP_KERNEL);
+	if (!apmclk) {
+		pr_err("%s: could not allocate APM clk\n", __func__);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	init.name = name;
+	init.ops = &xgene_clk_pll_ops;
+	init.flags = flags;
+	init.parent_names = parent_name ? &parent_name : NULL;
+	init.num_parents = parent_name ? 1 : 0;
+
+	apmclk->name = name;
+	apmclk->reg = reg;
+	apmclk->lock = lock;
+	apmclk->pll_offset = pll_offset;
+	apmclk->type = type;
+	apmclk->hw.init = &init;
+
+	/* Register the clock */
+	clk = clk_register(dev, &apmclk->hw);
+	if (IS_ERR(clk)) {
+		pr_err("%s: could not register clk %s\n", __func__, name);
+		kfree(apmclk);
+		return NULL;
+	}
+	return clk;
+}
+
+static void xgene_socpllclk_init(struct device_node *np)
+{
+        const char *clk_name = np->full_name;
+        struct clk *clk;
+        void *reg;
+
+        reg = of_iomap(np, 0);
+        if (reg == NULL) {
+                pr_err("Unable to map CSR register for %s\n", np->full_name);
+                return;
+        }
+        of_property_read_string(np, "clock-output-names", &clk_name);
+        clk = xgene_register_clk_pll(NULL,
+                        clk_name, of_clk_get_parent_name(np, 0),
+                        CLK_IS_ROOT, reg, 0, PLL_TYPE_SOC, &clk_lock);
+        if (!IS_ERR(clk)) {
+                of_clk_add_provider(np, of_clk_src_simple_get, clk);
+                clk_register_clkdev(clk, clk_name, NULL);
+                pr_debug("Add %s clock PLL\n", clk_name);
+        }
+}
+
+static void xgene_pcppllclk_init(struct device_node *np)
+{
+	const char *clk_name = np->full_name;
+	struct clk *clk;
+	void *reg;
+
+	reg = of_iomap(np, 0);
+	if (reg == NULL) {
+		pr_err("Unable to map CSR register for %s\n", np->full_name);
+		return;
+	}
+	of_property_read_string(np, "clock-output-names", &clk_name);
+	clk = xgene_register_clk_pll(NULL,
+			clk_name, of_clk_get_parent_name(np, 0),
+			CLK_IS_ROOT, reg, 0, PLL_TYPE_PCP, &clk_lock);
+	if (!IS_ERR(clk)) {
+		of_clk_add_provider(np, of_clk_src_simple_get, clk);
+		clk_register_clkdev(clk, clk_name, NULL);
+		pr_debug("Add %s clock PLL\n", clk_name);
+	}
+}
+
+/* IP Clock */
+struct xgene_dev_parameters {
+	u32  flags;			/* Any flags to the clock framework */
+	void __iomem *csr_reg;		/* CSR for IP clock */
+	u32 reg_clk_offset;		/* Offset to clock enable CSR */
+	u32 reg_clk_mask;		/* Mask bit for clock enable */
+	u32 reg_csr_offset;		/* Offset to CSR reset */
+	u32 reg_csr_mask;		/* Mask bit for disable CSR reset */
+	void __iomem *divider_reg;	/* CSR for divider */
+	u32 reg_divider_offset;		/* Offset to divider register */
+	u32 reg_divider_shift;		/* Bit shift to divider field */
+	u32 reg_divider_width;		/* Width of the bit to divider field */
+};
+
+struct xgene_clk {
+	struct clk_hw	hw;
+	const char	*name;
+	spinlock_t	*lock;
+	struct xgene_dev_parameters	param;
+};
+
+#define to_xgene_clk(_hw) container_of(_hw, struct xgene_clk, hw)
+
+static int xgene_clk_enable(struct clk_hw *hw)
+{
+	struct xgene_clk *pclk = to_xgene_clk(hw);
+	unsigned long flags = 0;
+	u32 data;
+
+	if (pclk->lock)
+		spin_lock_irqsave(pclk->lock, flags);
+
+	if (pclk->param.csr_reg != NULL) {
+		pr_debug("%s clock enabled\n", pclk->name);
+		/* First enable the clock */
+		data = xgene_clk_read(pclk->param.csr_reg +
+					pclk->param.reg_clk_offset);
+		data |= pclk->param.reg_clk_mask;
+		xgene_clk_write(data, pclk->param.csr_reg +
+					pclk->param.reg_clk_offset);
+		pr_debug("%s clock PADDR base 0x%016LX clk offset 0x%08X mask 0x%08X value 0x%08X\n",
+			pclk->name, __pa(pclk->param.csr_reg),
+			pclk->param.reg_clk_offset, pclk->param.reg_clk_mask,
+			data);
+
+		/* Second enable the CSR */
+		data = xgene_clk_read(pclk->param.csr_reg +
+					pclk->param.reg_csr_offset);
+		data &= ~pclk->param.reg_csr_mask;
+		xgene_clk_write(data, pclk->param.csr_reg +
+					pclk->param.reg_csr_offset);
+		pr_debug("%s CSR RESET PADDR base 0x%016LX csr offset 0x%08X mask 0x%08X value 0x%08X\n",
+			pclk->name, __pa(pclk->param.csr_reg),
+			pclk->param.reg_csr_offset, pclk->param.reg_csr_mask,
+			data);
+	}
+
+	if (pclk->lock)
+		spin_unlock_irqrestore(pclk->lock, flags);
+
+	return 0;
+}
+
+static void xgene_clk_disable(struct clk_hw *hw)
+{
+	struct xgene_clk *pclk = to_xgene_clk(hw);
+	unsigned long flags = 0;
+	u32 data;
+
+	if (pclk->lock)
+		spin_lock_irqsave(pclk->lock, flags);
+
+	if (pclk->param.csr_reg != NULL) {
+		pr_debug("%s clock disabled\n", pclk->name);
+		/* First put the CSR in reset */
+		data = xgene_clk_read(pclk->param.csr_reg +
+					pclk->param.reg_csr_offset);
+		data |= pclk->param.reg_csr_mask;
+		xgene_clk_write(data, pclk->param.csr_reg +
+					pclk->param.reg_csr_offset);
+
+		/* Second disable the clock */
+		data = xgene_clk_read(pclk->param.csr_reg +
+					pclk->param.reg_clk_offset);
+		data &= ~pclk->param.reg_clk_mask;
+		xgene_clk_write(data, pclk->param.csr_reg +
+					pclk->param.reg_clk_offset);
+	}
+
+	if (pclk->lock)
+		spin_unlock_irqrestore(pclk->lock, flags);
+}
+
+static int xgene_clk_is_enabled(struct clk_hw *hw)
+{
+	struct xgene_clk *pclk = to_xgene_clk(hw);
+	u32 data = 0;
+
+	if (pclk->param.csr_reg != NULL) {
+		pr_debug("%s clock checking\n", pclk->name);
+		data = xgene_clk_read(pclk->param.csr_reg +
+					pclk->param.reg_clk_offset);
+		pr_debug("%s clock is %s\n", pclk->name,
+			data & pclk->param.reg_clk_mask ? "enabled" :
+							"disabled");
+	}
+
+	if (pclk->param.csr_reg == NULL)
+		return 1;
+	return data & pclk->param.reg_clk_mask ? 1 : 0;
+}
+
+static unsigned long xgene_clk_recalc_rate(struct clk_hw *hw,
+				unsigned long parent_rate)
+{
+	struct xgene_clk *pclk = to_xgene_clk(hw);
+	u32 data;
+
+	if (pclk->param.divider_reg) {
+		data = xgene_clk_read(pclk->param.divider_reg +
+					pclk->param.reg_divider_offset);
+		data >>= pclk->param.reg_divider_shift;
+		data &= (1 << pclk->param.reg_divider_width) - 1;
+
+		pr_debug("%s clock recalc rate %ld parent %ld\n",
+			pclk->name, parent_rate / data, parent_rate);
+		return parent_rate / data;
+	} else {
+		pr_debug("%s clock recalc rate %ld parent %ld\n",
+			pclk->name, parent_rate, parent_rate);
+		return parent_rate;
+	}
+}
+
+static int xgene_clk_set_rate(struct clk_hw *hw, unsigned long rate,
+				unsigned long parent_rate)
+{
+	struct xgene_clk *pclk = to_xgene_clk(hw);
+	unsigned long flags = 0;
+	u32 data;
+	u32 divider;
+	u32 divider_save;
+
+	if (pclk->lock)
+		spin_lock_irqsave(pclk->lock, flags);
+
+	if (pclk->param.divider_reg) {
+		/* Let's compute the divider */
+		if (rate > parent_rate)
+			rate = parent_rate;
+		divider_save = divider = parent_rate / rate; /* Rounded down */
+		divider &= (1 << pclk->param.reg_divider_width) - 1;
+		divider <<= pclk->param.reg_divider_shift;
+
+		/* Set new divider */
+		data = xgene_clk_read(pclk->param.divider_reg +
+				pclk->param.reg_divider_offset);
+		data &= ~((1 << pclk->param.reg_divider_width) - 1);
+		data |= divider;
+		xgene_clk_write(data, pclk->param.divider_reg +
+					pclk->param.reg_divider_offset);
+		pr_debug("%s clock set rate %ld\n", pclk->name,
+			parent_rate / divider_save);
+	} else {
+		divider_save = 1;
+	}
+
+	if (pclk->lock)
+		spin_unlock_irqrestore(pclk->lock, flags);
+
+	return parent_rate / divider_save;
+}
+
+static long xgene_clk_round_rate(struct clk_hw *hw, unsigned long rate,
+				unsigned long *prate)
+{
+	struct xgene_clk *pclk = to_xgene_clk(hw);
+	unsigned long parent_rate = *prate;
+	u32 divider;
+
+	if (pclk->param.divider_reg) {
+		/* Let's compute the divider */
+		if (rate > parent_rate)
+			rate = parent_rate;
+		divider = parent_rate / rate;   /* Rounded down */
+	} else {
+		divider = 1;
+	}
+
+	return parent_rate / divider;
+}
+
+const struct clk_ops xgene_clk_ops = {
+	.enable = xgene_clk_enable,
+	.disable = xgene_clk_disable,
+	.is_enabled = xgene_clk_is_enabled,
+	.recalc_rate = xgene_clk_recalc_rate,
+	.set_rate = xgene_clk_set_rate,
+	.round_rate = xgene_clk_round_rate,
+};
+
+static struct clk *xgene_register_clk(struct device *dev,
+		const char *name, const char *parent_name,
+		struct xgene_dev_parameters *parameters, spinlock_t *lock)
+{
+	struct xgene_clk *apmclk;
+	struct clk *clk;
+	struct clk_init_data init;
+	int rc;
+
+	/* allocate the APM clock structure */
+	apmclk = kzalloc(sizeof(*apmclk), GFP_KERNEL);
+	if (!apmclk) {
+		pr_err("%s: could not allocate APM clk\n", __func__);
+		return ERR_PTR(-ENOMEM);
+	}
+
+	init.name = name;
+	init.ops = &xgene_clk_ops;
+	init.flags = parameters->flags;
+	init.parent_names = parent_name ? &parent_name : NULL;
+	init.num_parents = parent_name ? 1 : 0;
+
+	apmclk->name = name;
+	apmclk->lock = lock;
+	apmclk->hw.init = &init;
+	apmclk->param = *parameters;
+
+	/* Register the clock */
+	clk = clk_register(dev, &apmclk->hw);
+	if (IS_ERR(clk)) {
+		pr_err("%s: could not register clk %s\n", __func__, name);
+		kfree(apmclk);
+		return clk;
+	}
+
+	/* Register the clock for lookup */
+	rc = clk_register_clkdev(clk, name, NULL);
+	if (rc != 0) {
+		pr_err("%s: could not register lookup clk %s\n",
+			__func__, name);
+	}
+	return clk;
+}
+
+static void __init xgene_devclk_init(struct device_node *np)
+{
+	const char *clk_name = np->full_name;
+	struct clk *clk;
+	struct resource res;
+	int rc;
+	struct xgene_dev_parameters parameters;
+
+	rc = of_address_to_resource(np, 0, &res);
+	if (rc != 0) {
+		pr_err("no DTS CSR register for %s\n", np->full_name);
+		return;
+	}
+	if (resource_size(&res)) {
+		parameters.csr_reg = of_iomap(np, 0);
+		if (parameters.csr_reg == NULL) {
+			pr_err("Unable to map CSR register for %s\n",
+				np->full_name);
+			return;
+		}
+	} else {
+		parameters.csr_reg = NULL;
+	}
+
+	rc = of_address_to_resource(np, 1, &res);
+	if (rc != 0) {
+		pr_err("no DTS DIV register for %s\n", np->full_name);
+		return;
+	}
+	if (resource_size(&res)) {
+		parameters.divider_reg = of_iomap(np, 1);
+		if (parameters.divider_reg == NULL) {
+			pr_err("Unable to map DIV register for %s\n",
+				np->full_name);
+			if (parameters.csr_reg)
+				iounmap(parameters.csr_reg);
+			return;
+		}
+	} else {
+		parameters.divider_reg = NULL;
+	}
+	if (of_property_read_u32(np, "flags", &parameters.flags))
+		parameters.flags = 0;
+	if (of_property_read_u32(np, "csr-offset", &parameters.reg_csr_offset))
+		parameters.reg_csr_offset = 0;
+	if (of_property_read_u32(np, "csr-mask", &parameters.reg_csr_mask))
+		parameters.reg_csr_mask = 0xF;
+	if (of_property_read_u32(np, "enable-offset",
+				&parameters.reg_clk_offset))
+		parameters.reg_clk_offset = 0x8;
+	if (of_property_read_u32(np, "enable-mask", &parameters.reg_clk_mask))
+		parameters.reg_clk_mask = 0xF;
+	if (of_property_read_u32(np, "divider-offset",
+				&parameters.reg_divider_offset))
+		parameters.reg_divider_offset = 0;
+	if (of_property_read_u32(np, "divider-width",
+				&parameters.reg_divider_width))
+		parameters.reg_divider_width = 0;
+	if (of_property_read_u32(np, "divider-shift",
+				&parameters.reg_divider_shift))
+		parameters.reg_divider_shift = 0;
+	of_property_read_string(np, "clock-output-names", &clk_name);
+
+	clk = xgene_register_clk(NULL, clk_name,
+		of_clk_get_parent_name(np, 0), &parameters, &clk_lock);
+	if (IS_ERR(clk)) {
+		if (parameters.csr_reg)
+			iounmap(parameters.csr_reg);
+		if (parameters.divider_reg)
+			iounmap(parameters.divider_reg);
+		return;
+	}
+	pr_debug("Add %s clock\n", clk_name);
+	rc = of_clk_add_provider(np, of_clk_src_simple_get, clk);
+	if (rc != 0) {
+		pr_err("%s: could register provider clk %s\n", __func__,
+			np->full_name);
+		return;
+	}
+}
+
+CLK_OF_DECLARE(xgene_socpll_clock, "apm,xgene-socpll-clock", xgene_socpllclk_init);
+CLK_OF_DECLARE(xgene_pcppll_clock, "apm,xgene-pcppll-clock", xgene_pcppllclk_init);
+CLK_OF_DECLARE(xgene_dev_clock, "apm,xgene-device-clock", xgene_devclk_init);
-- 
1.5.5

[PATCH v3 2/3] clk: arm64: Add DTS clock entry for APM X-Gene Storm SoC

[Loc Ho]

clk: arm64: Add DTS clock entry for APM X-Gene Storm SoC with reference to
reference, PCP PLL, SoC PLL, and Ethernet clocks.

Signed-off-by: Loc Ho <lho@apm.com>
Signed-off-by: Kumar Sankaran <ksankaran@apm.com>
Signed-off-by: Vinayak Kale <vkale@apm.com>
Signed-off-by: Feng Kan <fkan@apm.com>
---
 arch/arm64/boot/dts/apm-storm.dtsi |   75 ++++++++++++++++++++++++++++++++++++
 1 files changed, 75 insertions(+), 0 deletions(-)

diff --git a/arch/arm64/boot/dts/apm-storm.dtsi b/arch/arm64/boot/dts/apm-storm.dtsi
index bfdc578..3f2ef74 100644
--- a/arch/arm64/boot/dts/apm-storm.dtsi
+++ b/arch/arm64/boot/dts/apm-storm.dtsi
@@ -103,6 +103,81 @@
 		#size-cells = <2>;
 		ranges;
 
+		clocks {
+			#address-cells = <2>;
+			#size-cells = <2>;
+			ranges;
+			refclk: refclk {
+				compatible = "fixed-clock";
+				#clock-cells = <1>;
+				clock-frequency = <100000000>;
+				clock-output-names = "refclk";
+			};
+
+			pcppll: pcppll at 17000100 {
+				compatible = "apm,xgene-pcppll-clock";
+				#clock-cells = <1>;
+				clocks = <&refclk 0>;
+				clock-names = "pcppll";
+				reg = <0x0 0x17000100 0x0 0x1000>;
+				clock-output-names = "pcppll";
+				type = <0>;
+			};
+
+			socpll: socpll at 17000120 {
+				compatible = "apm,xgene-socpll-clock";
+				#clock-cells = <1>;
+				clocks = <&refclk 0>;
+				clock-names = "socpll";
+				reg = <0x0 0x17000120 0x0 0x1000>;
+				clock-output-names = "socpll";
+				type = <1>;
+			};
+
+			socplldiv2: socplldiv2  {
+				compatible = "fixed-factor-clock";
+				#clock-cells = <1>;
+				clocks = <&socpll 0>;
+				clock-names = "socplldiv2";
+				clock-mult = <1>;
+				clock-div = <2>;
+				clock-output-names = "socplldiv2";
+			};
+
+			qmlclk: qmlclk {
+				compatible = "apm,xgene-device-clock";
+				#clock-cells = <1>;
+				clocks = <&socplldiv2 0>;
+				clock-names = "qmlclk";
+				reg = <0x0 0x1703C000 0x0 0x1000
+				       0x0 0x00000000 0x0 0x0000>;
+				clock-output-names = "qmlclk";
+			};
+
+			ethclk: ethclk {
+				compatible = "apm,xgene-device-clock";
+				#clock-cells = <1>;
+				clocks = <&socplldiv2 0>;
+				clock-names = "ethclk";
+				reg = <0x0 0x00000000 0x0 0x0000
+				       0x0 0x17000000 0x0 0x1000>;
+				divider-offset = <0x238>;
+				divider-width = <0x9>;
+				divider-shift = <0x0>;
+				clock-output-names = "ethclk";
+			};
+
+			eth8clk: eth8clk {
+				compatible = "apm,xgene-device-clock";
+				#clock-cells = <1>;
+				clocks = <&ethclk 0>;
+				clock-names = "eth8clk";
+				reg = <0x0 0x1702C000 0x0 0x1000
+				       0x0 0x00000000 0x0 0x0000>;
+				clock-output-names = "eth8clk";
+			};
+		};
+
 		serial0: serial at 1c020000 {
 			device_type = "serial";
 			compatible = "ns16550";
-- 
1.5.5

[PATCH v3 3/3] Documentation: Add documentation for APM X-Gene clock binding

[Loc Ho]

Documentation: Add documentation for APM X-Gene clock binding with PLL and
device clocks.

Signed-off-by: Loc Ho <lho@apm.com>
Signed-off-by: Kumar Sankaran <ksankaran@apm.com>
Signed-off-by: Vinayak Kale <vkale@apm.com>
Signed-off-by: Feng Kan <fkan@apm.com>
---
 Documentation/devicetree/bindings/clock/xgene.txt |   90 +++++++++++++++++++++
 1 files changed, 90 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/clock/xgene.txt

diff --git a/Documentation/devicetree/bindings/clock/xgene.txt b/Documentation/devicetree/bindings/clock/xgene.txt
new file mode 100644
index 0000000..4f864bd
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/xgene.txt
@@ -0,0 +1,90 @@
+Device Tree Clock bindings for APM X-Gene
+
+This binding uses the common clock binding[1].
+
+[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
+
+Required properties:
+- compatible : shall be one of the following:
+	"apm,xgene-socpll-clock" - for a X-Gene SoC PLL clock
+	"apm,xgene-pcppll-clock" - for a X-Gene PCP PLL clock
+	"apm,xgene-device-clock" - for a X-Gene device clock
+
+Required properties for SoC or PCP PLL clocks:
+- reg : shall be the physical PLL register address for the pll clock.
+- clocks : shall be the input parent clock phandle for the clock. This should
+	be the reference clock.
+- #clock-cells : shall be set to 1.
+- clock-output-names : shall be the name of the PLL referenced by derive
+  clock.
+Optional properties for PLL clocks:
+- clock-names : shall be the name of the PLL. If missing, use the device name.
+
+Required properties for device clocks:
+- reg : shall be the physical CSR reset address base and physical CSR divider
+        address base. If one does not exist, specify 0 for address and 0 for 
+        size.
+- clocks : shall be the input parent clock phandle for the clock.
+- #clock-cells : shall be set to 1.
+- clock-output-names : shall be the name of the device referenced.
+Optional properties for device clocks:
+- clock-names : shall be the name of the device clock. If missing, use the
+                device name.
+- flags : Any clock flags. ie. use 0x8 to leave clock un-touch if not
+          referenced. Default is 0.
+- csr-offset : Offset to the CSR reset register from the reset address base.
+               Default is 0.
+- csr-mask : CSR reset mask bit. Default is 0xF.
+- enable-offset : Offset to the enable register from the reset address base.
+                  Default is 0x8.
+- enable-mask : CSR enable mask bit. Default is 0xF.
+- divider-offset : Offset to the divider CSR register from the divider base.
+                   Default is 0x0.
+- divider-width : Width of the divider register. Default is 0.
+- divider-shift : Bit shift of the divider register. Default is 0.
+
+For example:
+
+	pcppll: pcppll at 17000100 {
+		compatible = "apm,xgene-pcppll-clock";
+		#clock-cells = <1>;
+		clocks = <&refclk 0>;
+		clock-names = "pcppll";
+		reg = <0x0 0x17000100 0x0 0x1000>;
+		clock-output-names = "pcppll";
+		type = <0>;
+	};
+
+	socpll: socpll at 17000120 {
+		compatible = "apm,xgene-socpll-clock";
+		#clock-cells = <1>;
+		clocks = <&refclk 0>;
+		clock-names = "socpll";
+		reg = <0x0 0x17000120 0x0 0x1000>;
+		clock-output-names = "socpll";
+		type = <1>;
+	};
+
+	qmlclk: qmlclk {
+		compatible = "apm,xgene-device-clock";
+		#clock-cells = <1>;
+		clocks = <&socplldiv2 0>;
+		clock-names = "qmlclk";
+		reg = <0x0 0x1703C000 0x0 0x1000
+			0x0 0x00000000 0x0 0x0000>;
+		clock-output-names = "qmlclk";
+	};
+
+	ethclk: ethclk {
+		compatible = "apm,xgene-device-clock";
+		#clock-cells = <1>;
+		clocks = <&socplldiv2 0>;
+		clock-names = "ethclk";
+		reg = <0x0 0x00000000 0x0 0x0000
+			0x0 0x17000000 0x0 0x1000>;
+			divider-offset = <0x238>;
+		divider-width = <0x9>;
+		divider-shift = <0x0>;
+		clock-output-names = "ethclk";
+	};
+
-- 
1.5.5

[PATCH v3 1/3] clk: Add APM X-Gene SoC clock driver for reference, PLL, and device clocks.

[Mark Rutland]

On Mon, Jun 24, 2013 at 08:01:25PM +0100, Loc Ho wrote:
> clk: Add APM X-Gene SoC clock driver for reference, PLL, and device clocks.
> 
> Signed-off-by: Loc Ho <lho@apm.com>
> Signed-off-by: Kumar Sankaran <ksankaran@apm.com>
> Signed-off-by: Vinayak Kale <vkale@apm.com>
> Signed-off-by: Feng Kan <fkan@apm.com>
> ---
>  drivers/clk/Kconfig     |    7 +
>  drivers/clk/Makefile    |    1 +
>  drivers/clk/clk-xgene.c |  538 +++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 546 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/clk/clk-xgene.c
 

[...]

> +static void __init xgene_devclk_init(struct device_node *np)
> +{
> +       const char *clk_name = np->full_name;
> +       struct clk *clk;
> +       struct resource res;
> +       int rc;
> +       struct xgene_dev_parameters parameters;
> +
> +       rc = of_address_to_resource(np, 0, &res);
> +       if (rc != 0) {
> +               pr_err("no DTS CSR register for %s\n", np->full_name);
> +               return;
> +       }
> +       if (resource_size(&res)) {
> +               parameters.csr_reg = of_iomap(np, 0);
> +               if (parameters.csr_reg == NULL) {
> +                       pr_err("Unable to map CSR register for %s\n",
> +                               np->full_name);
> +                       return;
> +               }

In my earlier post, I'd failed to understand what you were doing here --
testing that a reg represents a window of non-zero size.  I don't think
you need to describe the registers that aren't present at all, and I
believe you can use the more standard reg-names property to describe
this case. e.g. When you only have the "div" register bank, and not the
"csr" bank, you could describe this as:

some-clock {
	compatible = "apm,xgene-device-clock";
	reg = <0 0x12340000 0 0x1000>;
	reg-names = "div-reg";

	...
}

... and when you had both, you could describe this as:

some-clock {
	compatible = "apm,xgene-device-clock";
	reg = <0 0x12340000 0 0x1000>,
	      <0 0x23450000 0 0x1000>;
	reg-names = "div", "csr";

	...
}

This way, you don't describe registers that aren't actually present,
and it's clearer which register's which.

It looks like of_address_to_resource reads the reg-names property, so
you could test against the resource's name to figure out which reg you
have (if you only have one). My earlier comment to use of_iomap was
misplaced, as there doesn't seem to be anything like of_iomap_by_name,
and you have to use the resource anyway to get the name.

> +       } else {
> +               parameters.csr_reg = NULL;
> +       }
> +
> +       rc = of_address_to_resource(np, 1, &res);
> +       if (rc != 0) {
> +               pr_err("no DTS DIV register for %s\n", np->full_name);
> +               return;
> +       }
> +       if (resource_size(&res)) {
> +               parameters.divider_reg = of_iomap(np, 1);
> +               if (parameters.divider_reg == NULL) {
> +                       pr_err("Unable to map DIV register for %s\n",
> +                               np->full_name);
> +                       if (parameters.csr_reg)
> +                               iounmap(parameters.csr_reg);
> +                       return;
> +               }
> +       } else {
> +               parameters.divider_reg = NULL;
> +       }
> +       if (of_property_read_u32(np, "flags", &parameters.flags))
> +               parameters.flags = 0;

As mentioned previously, I believe you could use the standard status
property instead of flags.

Thanks,
Mark.

[PATCH v3 1/3] clk: Add APM X-Gene SoC clock driver for reference, PLL, and device clocks.

[Loc Ho]

Hi Mar,

>> +       if (of_property_read_u32(np, "flags", &parameters.flags))
>> +               parameters.flags = 0;
>
> As mentioned previously, I believe you could use the standard status
> property instead of flags.
[Loc Ho]
Okay... As mentioned, this will enforce multiple DTS file or patching
the DTS entry for clock as well as the driver DTS entry.

-Loc