ARM: ls1021a: add gating clocks to IP blocks.

A given application may not use all the peripherals on the device.
In this case, it may be desirable to disable unused peripherals.
DCFG provides a mechanism for gating clocks to IP blocks that are
not used when running an application.

Signed-off-by: Xiubo Li <Li.Xiubo@freescale.com>

---
This patch has been sent out to the community and under discussion：
URL：http://www.spinics.net/lists/arm-kernel/msg370133.html

Change-Id: Iedf07d12955b3fa011a0bef27236f73405cefb44
Reviewed-on: http://git.am.freescale.net:8181/21604
Tested-by: Review Code-CDREVIEW <CDREVIEW@freescale.com>
Reviewed-by: Dongsheng Wang <dongsheng.wang@freescale.com>
Reviewed-by: Zhengxiong Jin <Jason.Jin@freescale.com>

5 files changed, 283 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/clock/ls1021a-clock.txt b/Documentation/devicetree/bindings/clock/ls1021a-clock.txt
new file mode 100644
index 0000000..e53d976
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/ls1021a-clock.txt
@@ -0,0 +1,27 @@
+Gating clock bindings for Freescale LS1021A SOC
+
+Required properties:
+- compatible:		Should be "fsl,ls1021a-gate"
+- reg:			Address and length of the register set
+- #clock-cells:		Should be <1>
+
+The clock consumers should specify the desired clock by having one clock
+ID in its "clocks" phandle cell.
+Please see include/dt-bindings/clock/ls1021a-clock.h for the full list of
+LS1021A clock IDs.
+
+Example:
+
+gate: gate@1ee0000 {
+	compatible = "fsl,ls1021a-gate";
+	reg = <0x0 0x1ee0000 0x0 0x10000>;
+	#clock-cells = <1>;
+};
+
+wdog0: wdog@2ad0000 {
+	compatible = "fsl,ls1021a-wdt", "fsl,imx21-wdt";
+	reg = <0x0 0x2ad0000 0x0 0x10000>;
+	interrupts = <GIC_SPI 115 IRQ_TYPE_LEVEL_HIGH>;
+	clocks = <&gate LS1021A_CLK_WDOG12_EN>;
+	clock-names = "wdog12_en";
+};
diff --git a/arch/arm/mach-imx/Makefile b/arch/arm/mach-imx/Makefile
index 41b8044..aa7c93a 100644
--- a/arch/arm/mach-imx/Makefile
+++ b/arch/arm/mach-imx/Makefile
@@ -116,4 +116,6 @@ obj-$(CONFIG_SOC_VF610) += clk-vf610.o mach-vf610.o
 
 obj-$(CONFIG_SOC_LS1021A) += mach-ls1021a.o
 
+obj-$(CONFIG_SOC_LS1021A) += clk-ls1021a.o
+
 obj-y += devices/
diff --git a/arch/arm/mach-imx/clk-ls1021a.c b/arch/arm/mach-imx/clk-ls1021a.c
new file mode 100644
index 0000000..bba7c9a
--- /dev/null
+++ b/arch/arm/mach-imx/clk-ls1021a.c
@@ -0,0 +1,191 @@
+/*
+ * Copyright 2014 Freescale Semiconductor, Inc.
+ *
+ * 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.
+ */
+
+#include <linux/clk.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of_address.h>
+#include <linux/slab.h>
+#include <dt-bindings/clock/ls1021a-clock.h>
+
+#include "clk.h"
+
+static struct clk *clks[LS1021A_CLK_END];
+static struct clk_onecell_data clk_data;
+
+/* The DCFG registers are in big endian mode on LS1021A SoC */
+static u8 ls1021a_clk_shift_be(u8 shift)
+{
+	u8 m, n;
+
+	m = shift / 8;
+	n = shift % 8;
+
+	return (u8)((3 - m) * 8 + n);
+}
+
+static void __init ls1021a_clocks_init(struct device_node *np)
+{
+	static void __iomem *dcfg_base;
+	int i;
+
+#define DCFG_CCSR_DEVDISR1	(dcfg_base + 0x70)
+#define DCFG_CCSR_DEVDISR2	(dcfg_base + 0x74)
+#define DCFG_CCSR_DEVDISR3	(dcfg_base + 0x78)
+#define DCFG_CCSR_DEVDISR4	(dcfg_base + 0x7c)
+#define DCFG_CCSR_DEVDISR5	(dcfg_base + 0x80)
+#define DCFG_CCSR_RSTRQMR1	(dcfg_base + 0xc0)
+
+	if (dcfg_base) {
+		pr_warn("LS1021A gate clk has already added.\n");
+		return;
+	}
+
+	dcfg_base = of_iomap(np, 0);
+
+	BUG_ON(!dcfg_base);
+
+	clks[LS1021A_CLK_PBL_EN] = ls1021a_clk_gate("pbl_en", "dummy",
+						DCFG_CCSR_DEVDISR1,
+						ls1021a_clk_shift_be(0));
+	clks[LS1021A_CLK_ESDHC_EN] = ls1021a_clk_gate("esdhc_en", "dummy",
+						DCFG_CCSR_DEVDISR1,
+						ls1021a_clk_shift_be(2));
+	clks[LS1021A_CLK_DMA1_EN] = ls1021a_clk_gate("dma1_en", "dummy",
+						DCFG_CCSR_DEVDISR1,
+						ls1021a_clk_shift_be(8));
+	clks[LS1021A_CLK_DMA2_EN] = ls1021a_clk_gate("dma2_en", "dummy",
+						DCFG_CCSR_DEVDISR1,
+						ls1021a_clk_shift_be(9));
+	clks[LS1021A_CLK_USB3_PHY_EN] = ls1021a_clk_gate("usb3_phy_en", "dummy",
+						DCFG_CCSR_DEVDISR1,
+						ls1021a_clk_shift_be(12));
+	clks[LS1021A_CLK_USB2_EN] = ls1021a_clk_gate("usb2_en", "dummy",
+						DCFG_CCSR_DEVDISR1,
+						ls1021a_clk_shift_be(13));
+	clks[LS1021A_CLK_SATA_EN] = ls1021a_clk_gate("sata_en", "dummy",
+						DCFG_CCSR_DEVDISR1,
+						ls1021a_clk_shift_be(16));
+	clks[LS1021A_CLK_USB3_EN] = ls1021a_clk_gate("usb3_en", "dummy",
+						DCFG_CCSR_DEVDISR1,
+						ls1021a_clk_shift_be(17));
+	clks[LS1021A_CLK_SEC_EN] = ls1021a_clk_gate("sec_en", "dummy",
+						DCFG_CCSR_DEVDISR1,
+						ls1021a_clk_shift_be(22));
+	clks[LS1021A_CLK_2D_ACE_EN] = ls1021a_clk_gate("2d_ace_en", "dummy",
+						DCFG_CCSR_DEVDISR1,
+						ls1021a_clk_shift_be(30));
+	clks[LS1021A_CLK_QE_EN] = ls1021a_clk_gate("qe_en", "dummy",
+						DCFG_CCSR_DEVDISR1,
+						ls1021a_clk_shift_be(31));
+
+	clks[LS1021A_CLK_ETSEC1_EN] = ls1021a_clk_gate("etsec1_en", "dummy",
+						DCFG_CCSR_DEVDISR2,
+						ls1021a_clk_shift_be(0));
+	clks[LS1021A_CLK_ETSEC2_EN] = ls1021a_clk_gate("etsec2_en", "dummy",
+						DCFG_CCSR_DEVDISR2,
+						ls1021a_clk_shift_be(1));
+	clks[LS1021A_CLK_ETSEC3_EN] = ls1021a_clk_gate("etsec3_en", "dummy",
+						DCFG_CCSR_DEVDISR2,
+						ls1021a_clk_shift_be(2));
+
+	clks[LS1021A_CLK_PEX1_EN] = ls1021a_clk_gate("pex1_en", "dummy",
+						DCFG_CCSR_DEVDISR3,
+						ls1021a_clk_shift_be(0));
+	clks[LS1021A_CLK_PEX2_EN] = ls1021a_clk_gate("pex2_en", "dummy",
+						DCFG_CCSR_DEVDISR3,
+						ls1021a_clk_shift_be(1));
+
+	clks[LS1021A_CLK_DUART1_EN] = ls1021a_clk_gate("duart1_en", "dummy",
+						DCFG_CCSR_DEVDISR4,
+						ls1021a_clk_shift_be(2));
+	clks[LS1021A_CLK_DUART2_EN] = ls1021a_clk_gate("duart2_en", "dummy",
+						DCFG_CCSR_DEVDISR4,
+						ls1021a_clk_shift_be(3));
+	clks[LS1021A_CLK_QSPI_EN] = ls1021a_clk_gate("qspi_en", "dummy",
+						DCFG_CCSR_DEVDISR4,
+						ls1021a_clk_shift_be(4));
+
+	clks[LS1021A_CLK_DDR_EN] = ls1021a_clk_gate("ddr_en", "dummy",
+						DCFG_CCSR_DEVDISR5,
+						ls1021a_clk_shift_be(0));
+	clks[LS1021A_CLK_OCRAM1_EN] = ls1021a_clk_gate("ocram1_en", "dummy",
+						DCFG_CCSR_DEVDISR5,
+						ls1021a_clk_shift_be(4));
+	clks[LS1021A_CLK_IFC_EN] = ls1021a_clk_gate("ifc_en", "dummy",
+						DCFG_CCSR_DEVDISR5,
+						ls1021a_clk_shift_be(8));
+	clks[LS1021A_CLK_GPIO_EN] = ls1021a_clk_gate("gpio_en", "dummy",
+						DCFG_CCSR_DEVDISR5,
+						ls1021a_clk_shift_be(9));
+	clks[LS1021A_CLK_DBG_EN] = ls1021a_clk_gate("dbg_en", "dummy",
+						DCFG_CCSR_DEVDISR5,
+						ls1021a_clk_shift_be(10));
+	clks[LS1021A_CLK_FLEXCAN1_EN] = ls1021a_clk_gate("flexcan1_en", "dummy",
+						DCFG_CCSR_DEVDISR5,
+						ls1021a_clk_shift_be(12));
+	clks[LS1021A_CLK_FLEXCAN234_EN] = ls1021a_clk_gate("flexcan234_en",
+						"dummy", DCFG_CCSR_DEVDISR5,
+						ls1021a_clk_shift_be(13));
+	/* For flextimer 2/3/4/5/6/7/8 */
+	clks[LS1021A_CLK_FLEXTIMER_EN] = ls1021a_clk_gate("flextimer_en",
+						"dummy", DCFG_CCSR_DEVDISR5,
+						ls1021a_clk_shift_be(14));
+	clks[LS1021A_CLK_SECMON_EN] = ls1021a_clk_gate("secmon_en", "dummy",
+						DCFG_CCSR_DEVDISR5,
+						ls1021a_clk_shift_be(17));
+	clks[LS1021A_CLK_WDOG_EN] = ls1021a_clk_gate("wdog_en", "dummy",
+						DCFG_CCSR_RSTRQMR1,
+						ls1021a_clk_shift_be(22));
+	clks[LS1021A_CLK_WDOG12_EN] = ls1021a_clk_gate("wdog12_en", "wdog_en",
+						DCFG_CCSR_DEVDISR5,
+						ls1021a_clk_shift_be(21));
+	clks[LS1021A_CLK_I2C23_EN] = ls1021a_clk_gate("i2c23_en", "dummy",
+						DCFG_CCSR_DEVDISR5,
+						ls1021a_clk_shift_be(22));
+	/* For SAI 1/2/3/4 */
+	clks[LS1021A_CLK_SAI_EN] = ls1021a_clk_gate("sai_en", "dummy",
+						DCFG_CCSR_DEVDISR5,
+						ls1021a_clk_shift_be(23));
+	/* For lpuart 2/3/4/5/6  */
+	clks[LS1021A_CLK_LPUART_EN] = ls1021a_clk_gate("lpuart_en", "dummy",
+						DCFG_CCSR_DEVDISR5,
+						ls1021a_clk_shift_be(24));
+	clks[LS1021A_CLK_DSPI12_EN] = ls1021a_clk_gate("dspi12_en", "dummy",
+						DCFG_CCSR_DEVDISR5,
+						ls1021a_clk_shift_be(25));
+	clks[LS1021A_CLK_ASRC_EN] = ls1021a_clk_gate("asrc_en", "dummy",
+						DCFG_CCSR_DEVDISR5,
+						ls1021a_clk_shift_be(26));
+	clks[LS1021A_CLK_SPDIF_EN] = ls1021a_clk_gate("spdif_en", "dummy",
+						DCFG_CCSR_DEVDISR5,
+						ls1021a_clk_shift_be(27));
+	clks[LS1021A_CLK_I2C1_EN] = ls1021a_clk_gate("i2c1_en", "dummy",
+						DCFG_CCSR_DEVDISR5,
+						ls1021a_clk_shift_be(29));
+	clks[LS1021A_CLK_LPUART1_EN] = ls1021a_clk_gate("lpuart1_en", "dummy",
+						DCFG_CCSR_DEVDISR5,
+						ls1021a_clk_shift_be(30));
+	clks[LS1021A_CLK_FLEXTIMER1_EN] = ls1021a_clk_gate("flextimer1_en",
+						"dummy", DCFG_CCSR_DEVDISR5,
+						ls1021a_clk_shift_be(31));
+
+	for (i = 0; i < LS1021A_CLK_END; i++) {
+		if (IS_ERR(clks[i])) {
+			pr_err("LS1021A clk %d: register failed with %ld\n",
+			       i, PTR_ERR(clks[i]));
+			BUG();
+		}
+	}
+
+	/* Add the clocks to provider list */
+	clk_data.clks = clks;
+	clk_data.clk_num = LS1021A_CLK_END;
+	of_clk_add_provider(np, of_clk_src_onecell_get, &clk_data);
+}
+CLK_OF_DECLARE(ls1021a, "fsl,ls1021a-gate", ls1021a_clocks_init);
diff --git a/arch/arm/mach-imx/clk.h b/arch/arm/mach-imx/clk.h
index 048c5ad8..2a58d01 100644
--- a/arch/arm/mach-imx/clk.h
+++ b/arch/arm/mach-imx/clk.h
@@ -86,6 +86,14 @@ static inline struct clk *imx_clk_gate(const char *name, const char *parent,
 			shift, 0, &imx_ccm_lock);
 }
 
+static inline struct clk *ls1021a_clk_gate(const char *name, const char *parent,
+		void __iomem *reg, u8 shift)
+{
+	return clk_register_gate(NULL, name, parent, CLK_SET_RATE_PARENT |
+			CLK_IGNORE_UNUSED, reg,	shift,
+			CLK_GATE_SET_TO_DISABLE, &imx_ccm_lock);
+}
+
 static inline struct clk *imx_clk_mux(const char *name, void __iomem *reg,
 		u8 shift, u8 width, const char **parents, int num_parents)
 {
diff --git a/include/dt-bindings/clock/ls1021a-clock.h b/include/dt-bindings/clock/ls1021a-clock.h
new file mode 100644
index 0000000..09b47d7
--- /dev/null
+++ b/include/dt-bindings/clock/ls1021a-clock.h
@@ -0,0 +1,55 @@
+/*
+ * Copyright 2014 Freescale Semiconductor, Inc.
+ *
+ * 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.
+ */
+
+#ifndef __DT_BINDINGS_CLOCK_LS1021A_H
+#define __DT_BINDINGS_CLOCK_LS1021A_H
+
+#define LS1021A_CLK_DUMMY	0
+#define LS1021A_CLK_PBL_EN	1
+#define LS1021A_CLK_ESDHC_EN	2
+#define LS1021A_CLK_DMA1_EN	3
+#define LS1021A_CLK_DMA2_EN	4
+#define LS1021A_CLK_USB3_PHY_EN	5
+#define LS1021A_CLK_USB2_EN	6
+#define LS1021A_CLK_SATA_EN	7
+#define LS1021A_CLK_USB3_EN	8
+#define LS1021A_CLK_SEC_EN	9
+#define LS1021A_CLK_2D_ACE_EN	10
+#define LS1021A_CLK_QE_EN	11
+#define LS1021A_CLK_ETSEC1_EN	12
+#define LS1021A_CLK_ETSEC2_EN	13
+#define LS1021A_CLK_ETSEC3_EN	14
+#define LS1021A_CLK_PEX1_EN	15
+#define LS1021A_CLK_PEX2_EN	16
+#define LS1021A_CLK_DUART1_EN	17
+#define LS1021A_CLK_DUART2_EN	18
+#define LS1021A_CLK_QSPI_EN	19
+#define LS1021A_CLK_DDR_EN	20
+#define LS1021A_CLK_OCRAM1_EN	21
+#define LS1021A_CLK_IFC_EN	22
+#define LS1021A_CLK_GPIO_EN	23
+#define LS1021A_CLK_DBG_EN	24
+#define LS1021A_CLK_FLEXCAN1_EN	25
+#define LS1021A_CLK_FLEXCAN234_EN	26
+#define LS1021A_CLK_FLEXTIMER_EN	27
+#define LS1021A_CLK_SECMON_EN	28
+#define LS1021A_CLK_WDOG_EN	29
+#define LS1021A_CLK_WDOG12_EN	30
+#define LS1021A_CLK_I2C23_EN	31
+#define LS1021A_CLK_SAI_EN	32
+#define LS1021A_CLK_LPUART_EN	33
+#define LS1021A_CLK_DSPI12_EN	34
+#define LS1021A_CLK_ASRC_EN	35
+#define LS1021A_CLK_SPDIF_EN	36
+#define LS1021A_CLK_I2C1_EN	37
+#define LS1021A_CLK_LPUART1_EN	38
+#define LS1021A_CLK_FLEXTIMER1_EN	39
+#define LS1021A_CLK_END		40
+
+#endif /* __DT_BINDINGS_CLOCK_LS1021A_H */