diff mbox

[RFC,V2,7/8] ARM i.MX51/53: reimplement clock support

Message ID 1323854638-3455-8-git-send-email-richard.zhao@linaro.org
State RFC
Headers show

Commit Message

Richard Zhao Dec. 14, 2011, 9:23 a.m. UTC
Reimplement i.MX51/53 clock support. This is tested with a babbage
board and a loco board up to the point that UARTs, FEC and USB work.
There are surely bugs left in the code, but I found several in the
old code while reimplementing it, so who cares...
The implementation is mostly based on the datasheet and not the old
code.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Richard Zhao <richard.zhao@linaro.org>
---
 arch/arm/mach-mx5/Kconfig              |   14 +
 arch/arm/mach-mx5/Makefile             |    2 +-
 arch/arm/mach-mx5/clock-imx51-imx53.c  |  640 ++++++++++++++++++++++++++++++++
 arch/arm/plat-mxc/include/mach/clock.h |    3 +
 4 files changed, 658 insertions(+), 1 deletions(-)
 create mode 100644 arch/arm/mach-mx5/clock-imx51-imx53.c
diff mbox

Patch

diff --git a/arch/arm/mach-mx5/Kconfig b/arch/arm/mach-mx5/Kconfig
index af0c212..924930b 100644
--- a/arch/arm/mach-mx5/Kconfig
+++ b/arch/arm/mach-mx5/Kconfig
@@ -31,6 +31,13 @@  config	SOC_IMX51
 	select ARCH_MXC_AUDMUX_V2
 	select ARCH_HAS_CPUFREQ
 	select ARCH_MX51
+	select GENERIC_CLK
+	select GENERIC_CLK_FIXED
+	select GENERIC_CLK_DIVIDER
+	select GENERIC_CLK_MUX
+	select GENERIC_CLK_DUMMY
+	select IMX_CLK_PLLV2
+	select IMX_CLK_GATE2B
 
 config	SOC_IMX53
 	bool
@@ -39,6 +46,13 @@  config	SOC_IMX53
 	select MXC_TZIC
 	select ARCH_MXC_IOMUX_V3
 	select ARCH_MX53
+	select GENERIC_CLK
+	select GENERIC_CLK_FIXED
+	select GENERIC_CLK_DIVIDER
+	select GENERIC_CLK_MUX
+	select GENERIC_CLK_DUMMY
+	select IMX_CLK_PLLV2
+	select IMX_CLK_GATE2B
 
 #comment "i.MX50 machines:"
 
diff --git a/arch/arm/mach-mx5/Makefile b/arch/arm/mach-mx5/Makefile
index 0fc6080..b26438d 100644
--- a/arch/arm/mach-mx5/Makefile
+++ b/arch/arm/mach-mx5/Makefile
@@ -3,7 +3,7 @@ 
 #
 
 # Object file lists.
-obj-y   := cpu.o mm.o clock-mx51-mx53.o ehci.o system.o
+obj-y   := cpu.o mm.o clock-imx51-imx53.o ehci.o system.o
 
 obj-$(CONFIG_PM) += pm-imx5.o
 obj-$(CONFIG_CPU_FREQ_IMX)    += cpu_op-mx51.o
diff --git a/arch/arm/mach-mx5/clock-imx51-imx53.c b/arch/arm/mach-mx5/clock-imx51-imx53.c
new file mode 100644
index 0000000..8b7a218
--- /dev/null
+++ b/arch/arm/mach-mx5/clock-imx51-imx53.c
@@ -0,0 +1,640 @@ 
+/*
+ * Copyright 2010 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+#include <linux/mm.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/clkdev.h>
+
+#include <asm/div64.h>
+
+#include <mach/hardware.h>
+#include <mach/common.h>
+#include <mach/clock.h>
+
+#include "crm_regs.h"
+
+struct clk_dummy {
+	struct clk clk;
+};
+
+static struct clk_hw_ops dumy_ops;
+static struct clk_dummy dummy = {
+	.clk = {
+		.name = "dummy",
+		.ops = &dumy_ops,
+	},
+};
+
+static DEFINE_CLK_FIXED(ckil, 0);
+static DEFINE_CLK_FIXED(osc, 0);
+static DEFINE_CLK_FIXED(ckih1, 0);
+static DEFINE_CLK_FIXED(ckih2, 0);
+
+static DEFINE_CLK_PLLV2(pll1, &osc.clk, MX51_DPLL1_BASE);
+static DEFINE_CLK_PLLV2(pll2, &osc.clk, MX51_DPLL2_BASE);
+static DEFINE_CLK_PLLV2(pll3, &osc.clk, MX51_DPLL3_BASE);
+static DEFINE_CLK_PLLV2(pll4, &osc.clk, MX53_DPLL4_BASE);
+
+static struct clk_dummy dummy;
+
+/* Low-power Audio Playback Mode clock */
+static struct clk *lp_apm_sel[] = {
+	&osc.clk,
+	NULL,
+};
+static IMX_DEFINE_CLK_MUX(lp_apm, MXC_CCM_CCSR, 9, 1, lp_apm_sel);
+
+static IMX_DEFINE_CLK_DIVIDER(step_pll2_div, &pll2.clk, 0, MXC_CCM_CCSR, 5, 2);
+
+static IMX_DEFINE_CLK_DIVIDER(step_pll3_div, &pll3.clk, 0, MXC_CCM_CCSR, 3, 2);
+
+static struct clk *step_clk_sel[] = {
+	&lp_apm.clk,
+	NULL,
+	&step_pll2_div.clk,
+	&step_pll3_div.clk,
+};
+static IMX_DEFINE_CLK_MUX(step_clk, MXC_CCM_CCSR, 7, 2, step_clk_sel);
+
+static struct clk *pll1_sw_sel[] = {
+	&pll1.clk,
+	&step_clk.clk,
+};
+static IMX_DEFINE_CLK_MUX(pll1_sw, MXC_CCM_CCSR, 2, 1, pll1_sw_sel);
+
+static struct clk *pll2_sw_sel[] = {
+	&pll2.clk,
+	NULL,
+};
+static IMX_DEFINE_CLK_MUX(pll2_sw, MXC_CCM_CCSR, 1, 1, pll2_sw_sel);
+
+static struct clk *pll3_sw_sel[] = {
+	&pll3.clk,
+	NULL,
+};
+static IMX_DEFINE_CLK_MUX(pll3_sw, MXC_CCM_CCSR, 0, 1, pll3_sw_sel);
+
+static struct clk *pll4_sw_sel[] = {
+	&pll4.clk,
+	NULL,
+};
+static IMX_DEFINE_CLK_MUX(pll4_sw, MXC_CCM_CCSR, 9, 1, pll4_sw_sel);
+
+
+/* This is used multiple times */
+static struct clk *standard_pll_sel_clks[] = {
+	&pll1_sw.clk,
+	&pll2_sw.clk,
+	&pll3_sw.clk,
+	&lp_apm.clk,
+};
+
+static struct clk *periph_apm_sel[] = {
+	&pll1_sw.clk,
+	&pll3_sw.clk,
+	&lp_apm.clk,
+};
+static IMX_DEFINE_CLK_MUX(periph_apm, MXC_CCM_CBCMR, 12, 2, periph_apm_sel);
+
+static struct clk *main_bus_sel[] = {
+	&pll2_sw.clk,
+	&periph_apm.clk,
+};
+static IMX_DEFINE_CLK_MUX(main_bus, MXC_CCM_CBCDR, 25, 1, main_bus_sel);
+
+static IMX_DEFINE_CLK_DIVIDER(ahb_root, &main_bus.clk, 0, MXC_CCM_CBCDR, 10, 3);
+static IMX_DEFINE_CLK_DIVIDER(ipg, &ahb_root.clk, 0, MXC_CCM_CBCDR, 8, 2);
+
+static struct clk *perclk_lp_apm_sel[] = {
+	&main_bus.clk,
+	&lp_apm.clk,
+};
+static IMX_DEFINE_CLK_MUX(perclk_lp_apm, MXC_CCM_CBCMR, 1, 1, perclk_lp_apm_sel);
+
+static IMX_DEFINE_CLK_DIVIDER(perclk_pred1, &perclk_lp_apm.clk, 0, MXC_CCM_CBCDR, 6, 2);
+static IMX_DEFINE_CLK_DIVIDER(perclk_pred2, &perclk_pred1.clk, 0, MXC_CCM_CBCDR, 3, 3);
+static IMX_DEFINE_CLK_DIVIDER(perclk_podf, &perclk_pred2.clk, CLK_PARENT_SET_RATE, MXC_CCM_CBCDR, 0, 3);
+
+static struct clk *ipg_perclk_sel[] = {
+	&perclk_podf.clk,
+	&ipg.clk,
+};
+static IMX_DEFINE_CLK_MUX(ipg_perclk, MXC_CCM_CBCMR, 0, 1, ipg_perclk_sel);
+
+static IMX_DEFINE_CLK_DIVIDER(axi_a, &main_bus.clk, 0, MXC_CCM_CBCDR, 16, 3);
+static IMX_DEFINE_CLK_DIVIDER(axi_b, &main_bus.clk, 0, MXC_CCM_CBCDR, 19, 3);
+
+static struct clk *emi_slow_sel_clks[] = {
+	&main_bus.clk,
+	&ahb_root.clk,
+};
+static IMX_DEFINE_CLK_MUX(emi_sel, MXC_CCM_CBCDR, 26, 1, emi_slow_sel_clks);
+static IMX_DEFINE_CLK_DIVIDER(emi_slow_podf, &emi_sel.clk, 0, MXC_CCM_CBCDR, 22, 3);
+static IMX_DEFINE_CLK_DIVIDER(nfc_podf, &emi_slow_podf.clk, 0, MXC_CCM_CBCDR, 13, 3);
+
+static struct clk *xpu_sel[] = {
+	&axi_a.clk,
+	&axi_b.clk,
+	&emi_slow_podf.clk,
+	&ahb_root.clk,
+};
+static IMX_DEFINE_CLK_MUX(gpu2d, MXC_CCM_CBCMR, 16, 2, xpu_sel);
+static IMX_DEFINE_CLK_MUX(arm_axi, MXC_CCM_CBCMR, 8, 2, xpu_sel);
+static IMX_DEFINE_CLK_MUX(ipu_hsp, MXC_CCM_CBCMR, 6, 2, xpu_sel);
+static IMX_DEFINE_CLK_MUX(gpu, MXC_CCM_CBCMR, 4, 2, xpu_sel);
+static IMX_DEFINE_CLK_MUX(vpu_axi_root, MXC_CCM_CBCMR, 14, 2, xpu_sel);
+static IMX_DEFINE_CLK_MUX(ddr_root, MXC_CCM_CBCMR, 10, 2, xpu_sel);
+
+static IMX_DEFINE_CLK_DIVIDER(ddr_hf_mx51, &pll1_sw.clk, 0, MXC_CCM_CBCDR, 27, 3);
+static struct clk *ddr_hf_sel[] = {
+	&ddr_root.clk,
+	&ddr_hf_mx51.clk,
+};
+static IMX_DEFINE_CLK_MUX(ddr_root_mx51, MXC_CCM_CBCDR, 30, 1, ddr_hf_sel);
+
+static IMX_DEFINE_CLK_MUX(uart_sel, MXC_CCM_CSCMR1, 24, 2, standard_pll_sel_clks);
+static IMX_DEFINE_CLK_DIVIDER(uart_pred, &uart_sel.clk, 0, MXC_CCM_CSCDR1, 3, 3);
+static IMX_DEFINE_CLK_DIVIDER(uart_root, &uart_pred.clk, CLK_PARENT_SET_RATE, MXC_CCM_CSCDR1, 0, 3);
+
+static IMX_DEFINE_CLK_MUX(esdhc1_sel, MXC_CCM_CSCMR1, 20, 2, standard_pll_sel_clks);
+static IMX_DEFINE_CLK_DIVIDER(esdhc1_pred, &esdhc1_sel.clk, 0, MXC_CCM_CSCDR1, 16, 3);
+static IMX_DEFINE_CLK_DIVIDER(esdhc1_podf, &esdhc1_pred.clk, CLK_PARENT_SET_RATE, MXC_CCM_CSCDR1, 11, 3);
+
+/* This is routed to esdhc3 in the i.MX53 datasheet */
+static IMX_DEFINE_CLK_MUX(esdhc2_sel, MXC_CCM_CSCMR1, 16, 2, standard_pll_sel_clks);
+static IMX_DEFINE_CLK_DIVIDER(esdhc2_pred, &esdhc2_sel.clk, 0, MXC_CCM_CSCDR1, 22, 3);
+static IMX_DEFINE_CLK_DIVIDER(esdhc2_podf, &esdhc2_pred.clk, CLK_PARENT_SET_RATE, MXC_CCM_CSCDR1, 19, 3);
+
+static struct clk *esdhc3_sel_clks[] = {
+	&esdhc1_podf.clk,
+	&esdhc2_podf.clk,
+};
+static IMX_DEFINE_CLK_MUX(esdhc3_sel, MXC_CCM_CSCMR1, 19, 1, esdhc3_sel_clks);
+
+static struct clk *esdhc4_sel_clks[] = {
+	&esdhc1_podf.clk,
+	&esdhc2_podf.clk,
+};
+static IMX_DEFINE_CLK_MUX(esdhc4_sel, MXC_CCM_CSCMR1, 18, 1, esdhc4_sel_clks);
+
+static struct clk *ssi_apm_sel[] = {
+	&ckih1.clk,
+	&lp_apm.clk,
+	&ckih2.clk,
+};
+static IMX_DEFINE_CLK_MUX(ssi_lp_apm, MXC_CCM_CSCMR1, 8, 2, ssi_apm_sel);
+static IMX_DEFINE_CLK_MUX(ssi1_clk_sel, MXC_CCM_CSCMR1, 14, 2, standard_pll_sel_clks);
+static IMX_DEFINE_CLK_DIVIDER(ssi1_clk_pred, &ssi1_clk_sel.clk, 0, MXC_CCM_CS1CDR, 6, 3);
+static IMX_DEFINE_CLK_DIVIDER(ssi1_clk, &ssi1_clk_pred.clk, CLK_PARENT_SET_RATE, MXC_CCM_CS1CDR, 0, 6);
+static IMX_DEFINE_CLK_MUX(ssi2_clk_sel, MXC_CCM_CSCMR1, 12, 2, standard_pll_sel_clks);
+static IMX_DEFINE_CLK_DIVIDER(ssi2_clk_pred, &ssi2_clk_sel.clk, 0, MXC_CCM_CS2CDR, 6, 3);
+static IMX_DEFINE_CLK_DIVIDER(ssi2_clk, &ssi2_clk_pred.clk, CLK_PARENT_SET_RATE, MXC_CCM_CS2CDR, 0, 6);
+static struct clk *ssi3_clk_sel[] = {
+	&ssi1_clk.clk,
+	&ssi2_clk.clk,
+};
+static IMX_DEFINE_CLK_MUX(ssi3_clk, MXC_CCM_CSCMR1, 11, 1, ssi3_clk_sel);
+
+static IMX_DEFINE_CLK_MUX(ecspi_sel, MXC_CCM_CSCMR1, 4, 2, standard_pll_sel_clks);
+static IMX_DEFINE_CLK_DIVIDER(ecspi_pred, &ecspi_sel.clk, 0, MXC_CCM_CSCDR2, 25, 3);
+static IMX_DEFINE_CLK_DIVIDER(ecspi_podf, &ecspi_pred.clk, CLK_PARENT_SET_RATE, MXC_CCM_CSCDR2, 19, 6);
+
+static IMX_DEFINE_CLK_MUX(usboh3_sel, MXC_CCM_CSCMR1, 22, 2, standard_pll_sel_clks);
+static IMX_DEFINE_CLK_DIVIDER(usboh3_pred, &usboh3_sel.clk, 0, MXC_CCM_CSCDR1, 8, 3);
+static IMX_DEFINE_CLK_DIVIDER(usboh3_podf, &usboh3_pred.clk, CLK_PARENT_SET_RATE, MXC_CCM_CSCDR1, 6, 2);
+
+static IMX_DEFINE_CLK_DIVIDER(usb_phy_pred, &pll3_sw.clk, 0, MXC_CCM_CDCDR, 3, 3);
+static IMX_DEFINE_CLK_DIVIDER(usb_phy_podf, &usb_phy_pred.clk, CLK_PARENT_SET_RATE, MXC_CCM_CDCDR, 0, 3);
+static struct clk *usb_phy_sel_clks[] = {
+	&osc.clk,
+	&usb_phy_podf.clk,
+};
+static IMX_DEFINE_CLK_MUX(usb_phy_sel, MXC_CCM_CSCMR1, 26, 1, usb_phy_sel_clks);
+
+static IMX_DEFINE_CLK_DIVIDER(cpu_podf, &pll1_sw.clk, 0, MXC_CCM_CACRR, 0, 3);
+
+static struct clk *ipu_di0_sel_clks[] = {
+	&pll3_sw.clk,
+	&osc.clk,
+	&ckih1.clk,
+	NULL, /* &tve_di.clk */
+	NULL, /* ipp di0 (iomux) */
+	NULL, /* ldp di0 */
+};
+static IMX_DEFINE_CLK_MUX(ipu_di0_sel, MXC_CCM_CSCMR2, 26, 3, ipu_di0_sel_clks);
+
+static struct clk *ipu_di1_sel_clks[] = {
+	&pll3_sw.clk,
+	&osc.clk,
+	&ckih1.clk,
+	NULL, /* &tve_di.clk */
+	NULL, /* ipp di1 (iomux) */
+	NULL, /* ldp di1 */
+};
+static IMX_DEFINE_CLK_MUX(ipu_di1_sel, MXC_CCM_CSCMR2, 29, 3, ipu_di1_sel_clks);
+
+static struct clk *tve_ext_sel_clks[] = {
+	&osc.clk,
+	&ckih1.clk,
+};
+static IMX_DEFINE_CLK_MUX(tve_ext_sel, MXC_CCM_CSCMR1, 6, 1, tve_ext_sel_clks);
+
+static IMX_DEFINE_CLK_DIVIDER(tve_pred, &pll3_sw.clk, 0, MXC_CCM_CDCDR, 28, 3);
+
+static struct clk *tve_sel_clks[] = {
+	&tve_pred.clk,
+	&tve_ext_sel.clk,
+};
+static IMX_DEFINE_CLK_MUX(tve_sel, MXC_CCM_CSCMR1, 7, 1, tve_sel_clks);
+
+static DEFINE_CLK_GATE2B(ahbmux1, &ipg.clk, MXC_CCM_CCGR0, 8);
+static DEFINE_CLK_GATE2B(aips_tz1, &ipg.clk, MXC_CCM_CCGR0, 12);
+static DEFINE_CLK_GATE2B(aips_tz2, &ipg.clk, MXC_CCM_CCGR0, 13);
+static DEFINE_CLK_GATE2B(ahb_max, &ipg.clk, MXC_CCM_CCGR0, 14);
+static DEFINE_CLK_GATE2B(iim_gate, &ipg.clk, MXC_CCM_CCGR0, 15);
+
+static DEFINE_CLK_GATE2B(uart1_ipg_gate, &ipg.clk, MXC_CCM_CCGR1, 3);
+static DEFINE_CLK_GATE2B(uart1_per_gate, &uart_root.clk, MXC_CCM_CCGR1, 4);
+static DEFINE_CLK_GATE2B(uart2_ipg_gate, &ipg.clk, MXC_CCM_CCGR1, 5);
+static DEFINE_CLK_GATE2B(uart2_per_gate, &uart_root.clk, MXC_CCM_CCGR1, 6);
+static DEFINE_CLK_GATE2B(uart3_ipg_gate, &ipg.clk, MXC_CCM_CCGR1, 7);
+static DEFINE_CLK_GATE2B(uart3_per_gate, &uart_root.clk, MXC_CCM_CCGR1, 8);
+static DEFINE_CLK_GATE2B(i2c1_gate, &ipg_perclk.clk, MXC_CCM_CCGR1, 9);
+static DEFINE_CLK_GATE2B(i2c2_gate, &ipg_perclk.clk, MXC_CCM_CCGR1, 10);
+static DEFINE_CLK_GATE2B(hsi2c_gate, &ipg.clk, MXC_CCM_CCGR1, 11);
+
+static DEFINE_CLK_GATE2B(mx51_usb_phy_gate, &usb_phy_sel.clk, MXC_CCM_CCGR2, 0);
+static DEFINE_CLK_GATE2B(gpt_ipg_gate, &ipg.clk, MXC_CCM_CCGR2, 10);
+static DEFINE_CLK_GATE2B(pwm1_ipg_gate, &ipg.clk, MXC_CCM_CCGR2, 5);
+static DEFINE_CLK_GATE2B(pwm1_hf_gate, &ipg_perclk.clk, MXC_CCM_CCGR2, 6);
+static DEFINE_CLK_GATE2B(pwm2_ipg_gate, &ipg.clk, MXC_CCM_CCGR2, 7);
+static DEFINE_CLK_GATE2B(pwm2_hf_gate, &ipg_perclk.clk, MXC_CCM_CCGR2, 8);
+static DEFINE_CLK_GATE2B(gpt_gate, &ipg.clk, MXC_CCM_CCGR2, 9);
+static DEFINE_CLK_GATE2B(fec_gate, &ipg.clk, MXC_CCM_CCGR2, 12);
+static DEFINE_CLK_GATE2B(usboh3_ahb_gate, &ipg.clk, MXC_CCM_CCGR2, 13);
+static DEFINE_CLK_GATE2B(usboh3_gate, &usboh3_podf.clk, MXC_CCM_CCGR2, 14);
+static DEFINE_CLK_GATE2B(tve_gate, &tve_sel.clk, MXC_CCM_CCGR2, 15);
+
+static DEFINE_CLK_GATE2B(esdhc1_ipg_gate, &ipg.clk, MXC_CCM_CCGR3, 0);
+static DEFINE_CLK_GATE2B(esdhc1_per_gate, &esdhc1_podf.clk, MXC_CCM_CCGR3, 1);
+static DEFINE_CLK_GATE2B(esdhc2_ipg_gate, &ipg.clk, MXC_CCM_CCGR3, 2);
+static DEFINE_CLK_GATE2B(esdhc2_per_gate, &esdhc2_podf.clk, MXC_CCM_CCGR3, 3);
+static DEFINE_CLK_GATE2B(esdhc3_ipg_gate, &ipg.clk, MXC_CCM_CCGR3, 4);
+static DEFINE_CLK_GATE2B(esdhc3_per_gate, &esdhc3_sel.clk, MXC_CCM_CCGR3, 5);
+static DEFINE_CLK_GATE2B(esdhc4_ipg_gate, &ipg.clk, MXC_CCM_CCGR3, 6);
+static DEFINE_CLK_GATE2B(esdhc4_per_gate, &esdhc4_sel.clk, MXC_CCM_CCGR3, 7);
+static DEFINE_CLK_GATE2B(ssi1_ipg_gate, &ipg.clk, MXC_CCM_CCGR3, 8);
+static DEFINE_CLK_GATE2B(ssi1_gate, &ssi1_clk.clk, MXC_CCM_CCGR3, 9);
+static DEFINE_CLK_GATE2B(ssi2_ipg_gate, &ipg.clk, MXC_CCM_CCGR3, 10);
+static DEFINE_CLK_GATE2B(ssi2_gate, &ssi2_clk.clk, MXC_CCM_CCGR3, 11);
+static DEFINE_CLK_GATE2B(ssi3_ipg_gate, &ipg.clk, MXC_CCM_CCGR3, 12);
+static DEFINE_CLK_GATE2B(ssi3_gate, &ssi3_clk.clk, MXC_CCM_CCGR3, 13);
+
+static DEFINE_CLK_GATE2B(mx51_mipi_hsc1_gate, &ipg.clk, MXC_CCM_CCGR4, 3);
+static DEFINE_CLK_GATE2B(mx51_mipi_hsc2_gate, &ipg.clk, MXC_CCM_CCGR4, 4);
+static DEFINE_CLK_GATE2B(mx51_mipi_esc_gate, &ipg.clk, MXC_CCM_CCGR4, 5);
+static DEFINE_CLK_GATE2B(mx51_mipi_hsp_gate, &ipg.clk, MXC_CCM_CCGR4, 6);
+
+static DEFINE_CLK_GATE2B(mx53_usb_phy1_gate, &usb_phy_sel.clk, MXC_CCM_CCGR4, 5);
+static DEFINE_CLK_GATE2B(mx53_usb_phy2_gate, &usb_phy_sel.clk, MXC_CCM_CCGR4, 6);
+static DEFINE_CLK_GATE2B(ecspi1_ipg_gate, &ipg.clk, MXC_CCM_CCGR4, 9);
+static DEFINE_CLK_GATE2B(ecspi1_per_gate, &ecspi_podf.clk, MXC_CCM_CCGR4, 10);
+static DEFINE_CLK_GATE2B(ecspi2_ipg_gate, &ipg.clk, MXC_CCM_CCGR4, 11);
+static DEFINE_CLK_GATE2B(ecspi2_per_gate, &ecspi_podf.clk, MXC_CCM_CCGR4, 12);
+static DEFINE_CLK_GATE2B(cspi_ipg_gate, &ipg.clk, MXC_CCM_CCGR4, 13);
+static DEFINE_CLK_GATE2B(sdma_gate, &ipg.clk, MXC_CCM_CCGR4, 15);
+
+static DEFINE_CLK_GATE2B(ipu_gate, &ipu_hsp.clk, MXC_CCM_CCGR5, 5);
+static DEFINE_CLK_GATE2B(emi_fast_gate, &dummy.clk, MXC_CCM_CCGR5, 7);
+static DEFINE_CLK_GATE2B(emi_slow_gate, &emi_slow_podf.clk, MXC_CCM_CCGR5, 8);
+static DEFINE_CLK_GATE2B(nfc_gate, &nfc_podf.clk, MXC_CCM_CCGR5, 10);
+
+static DEFINE_CLK_GATE2B(ipu_di0_gate, &ipu_di0_sel.clk, MXC_CCM_CCGR6, 5);
+static DEFINE_CLK_GATE2B(ipu_di1_gate, &ipu_di1_sel.clk, MXC_CCM_CCGR6, 6);
+
+#define _REGISTER_CLKDEV(d, n, c) \
+	{ \
+		.dev_id = d, \
+		.con_id = n, \
+		.clk = c,   \
+	},
+
+static struct clk_lookup mx5_lookups[] = {
+	_REGISTER_CLKDEV("imx21-uart.0", NULL, &uart1_per_gate.clk)
+	_REGISTER_CLKDEV("imx21-uart.1", NULL, &uart2_per_gate.clk)
+	_REGISTER_CLKDEV("imx21-uart.2", NULL, &uart3_per_gate.clk)
+	_REGISTER_CLKDEV("mxc_pwm.0", "pwm", &pwm1_ipg_gate.clk)
+	_REGISTER_CLKDEV("mxc_pwm.1", "pwm", &pwm2_ipg_gate.clk)
+	_REGISTER_CLKDEV("imx-i2c.0", NULL, &i2c1_gate.clk)
+	_REGISTER_CLKDEV("imx-i2c.1", NULL, &i2c2_gate.clk)
+	_REGISTER_CLKDEV("mxc-ehci.0", "usb", &usboh3_gate.clk)
+	_REGISTER_CLKDEV("mxc-ehci.0", "usb_ahb", &usboh3_ahb_gate.clk)
+	_REGISTER_CLKDEV("mxc-ehci.0", "usb_phy1", &mx53_usb_phy1_gate.clk)
+	_REGISTER_CLKDEV("mxc-ehci.1", "usb", &usboh3_gate.clk)
+	_REGISTER_CLKDEV("mxc-ehci.1", "usb_ahb", &usboh3_ahb_gate.clk)
+	_REGISTER_CLKDEV("mxc-ehci.2", "usb", &usboh3_gate.clk)
+	_REGISTER_CLKDEV("mxc-ehci.2", "usb_ahb", &usboh3_ahb_gate.clk)
+	_REGISTER_CLKDEV("fsl-usb2-udc", "usb", &usboh3_gate.clk)
+	_REGISTER_CLKDEV("fsl-usb2-udc", "usb_ahb", &usboh3_ahb_gate.clk)
+	_REGISTER_CLKDEV("mxc_nand", NULL, &nfc_gate.clk)
+	_REGISTER_CLKDEV("imx-ssi.0", NULL, &ssi1_gate.clk)
+	_REGISTER_CLKDEV("imx-ssi.1", NULL, &ssi2_gate.clk)
+	_REGISTER_CLKDEV("imx-ssi.2", NULL, &ssi3_gate.clk)
+	_REGISTER_CLKDEV("imx-sdma", NULL, &sdma_gate.clk)
+	_REGISTER_CLKDEV("imx51-ecspi.0", NULL, &ecspi1_per_gate.clk)
+	_REGISTER_CLKDEV("imx51-ecspi.1", NULL, &ecspi2_per_gate.clk)
+	_REGISTER_CLKDEV("imx51-cspi.0", NULL, &cspi_ipg_gate.clk)
+	_REGISTER_CLKDEV(NULL, "cpu", &cpu_podf.clk)
+	_REGISTER_CLKDEV(NULL, "iim", &iim_gate.clk)
+	_REGISTER_CLKDEV("sdhci-esdhc-imx.0", NULL, &esdhc1_per_gate.clk)
+	_REGISTER_CLKDEV("sdhci-esdhc-imx.1", NULL, &esdhc2_per_gate.clk)
+	_REGISTER_CLKDEV("sdhci-esdhc-imx.2", NULL, &esdhc3_per_gate.clk)
+	_REGISTER_CLKDEV("sdhci-esdhc-imx.3", NULL, &esdhc4_per_gate.clk)
+	_REGISTER_CLKDEV("imx-ipuv3", NULL, &ipu_gate.clk)
+	_REGISTER_CLKDEV("imx-ipuv3", "di0", &ipu_di0_gate.clk)
+	_REGISTER_CLKDEV("imx-ipuv3", "di1", &ipu_di1_gate.clk)
+	_REGISTER_CLKDEV("imx2-wdt.0", NULL, &dummy.clk)
+	_REGISTER_CLKDEV("imx2-wdt.1", NULL, &dummy.clk)
+	_REGISTER_CLKDEV("imx-keypad", NULL, &dummy.clk)
+};
+
+static struct clk_lookup mx51_lookups[] = {
+	_REGISTER_CLKDEV("imx-i2c.2", NULL, &hsi2c_gate.clk)
+	_REGISTER_CLKDEV("imx27-fec.0", NULL, &fec_gate.clk)
+	_REGISTER_CLKDEV(NULL, "mipi_hsp", &mx51_mipi_hsp_gate.clk)
+};
+
+static struct clk_lookup mx53_lookups[] = {
+	_REGISTER_CLKDEV("imx25-fec.0", NULL, &fec_gate.clk)
+};
+
+struct clk *mx5_on_clocks[] = {
+	&uart1_ipg_gate.clk,
+	&uart2_ipg_gate.clk,
+	&uart3_ipg_gate.clk,
+	&gpt_ipg_gate.clk,
+	&esdhc1_ipg_gate.clk,
+	&esdhc2_ipg_gate.clk,
+	&esdhc3_ipg_gate.clk,
+	&esdhc4_ipg_gate.clk,
+	&ecspi1_ipg_gate.clk,
+	&ecspi2_ipg_gate.clk,
+	&cspi_ipg_gate.clk,
+};
+
+/*
+ * TODO: macro help limit the effect of clk api change.
+ * May be removed finally.
+ */
+#define _REGISTER_CLK(_clk, _ops, _flags) \
+		&(_clk).clk,
+
+struct clk *mx5_clk_array[] = {
+	_REGISTER_CLK(ckil, &clk_fixed_ops, CLK_IS_ROOT)
+	_REGISTER_CLK(osc, &clk_fixed_ops, CLK_IS_ROOT)
+	_REGISTER_CLK(ckih1, &clk_fixed_ops, CLK_IS_ROOT)
+	_REGISTER_CLK(ckih2, &clk_fixed_ops, CLK_IS_ROOT)
+	_REGISTER_CLK(pll1, &clk_pllv2_ops, 0)
+	_REGISTER_CLK(pll2, &clk_pllv2_ops, 0)
+	_REGISTER_CLK(pll3, &clk_pllv2_ops, 0)
+	/*
+	 * pll4 is only used by mx53. we put it here because
+	 * tve_ext_sel use it early
+	*/
+	_REGISTER_CLK(pll4, &clk_pllv2_ops, 0)
+	_REGISTER_CLK(pll4_sw, &clk_mux_ops, 0)
+	_REGISTER_CLK(dummy, &clk_dummy_ops, CLK_IS_ROOT)
+	_REGISTER_CLK(lp_apm, &clk_mux_ops, 0)
+	_REGISTER_CLK(step_pll2_div, &clk_divider_ops, 0)
+	_REGISTER_CLK(step_pll3_div, &clk_divider_ops, 0)
+	_REGISTER_CLK(step_clk, &clk_mux_ops, 0)
+	_REGISTER_CLK(pll1_sw, &clk_mux_ops, 0)
+	_REGISTER_CLK(pll2_sw, &clk_mux_ops, 0)
+	_REGISTER_CLK(pll3_sw, &clk_mux_ops, 0)
+	_REGISTER_CLK(periph_apm, &clk_mux_ops, 0)
+	_REGISTER_CLK(main_bus, &clk_mux_ops, 0)
+	_REGISTER_CLK(ahb_root, &clk_divider_ops, 0)
+	_REGISTER_CLK(ipg, &clk_divider_ops, 0)
+	_REGISTER_CLK(perclk_lp_apm, &clk_mux_ops, 0)
+	_REGISTER_CLK(perclk_pred1, &clk_divider_ops, 0)
+	_REGISTER_CLK(perclk_pred2, &clk_divider_ops, 0)
+	_REGISTER_CLK(perclk_podf, &clk_divider_ops, HINT_PARENT_RATE_CHANGE)
+	_REGISTER_CLK(ipg_perclk, &clk_mux_ops, 0)
+	_REGISTER_CLK(axi_a, &clk_divider_ops, 0)
+	_REGISTER_CLK(axi_b, &clk_divider_ops, 0)
+	_REGISTER_CLK(gpu2d, &clk_mux_ops, 0)
+	_REGISTER_CLK(arm_axi, &clk_mux_ops, 0)
+	_REGISTER_CLK(ipu_hsp, &clk_mux_ops, 0)
+	_REGISTER_CLK(gpu, &clk_mux_ops, 0)
+	_REGISTER_CLK(vpu_axi_root, &clk_mux_ops, 0)
+	_REGISTER_CLK(ddr_root, &clk_mux_ops, 0)
+	_REGISTER_CLK(uart_sel, &clk_mux_ops, 0)
+	_REGISTER_CLK(uart_pred, &clk_divider_ops, 0)
+	_REGISTER_CLK(uart_root, &clk_divider_ops, HINT_PARENT_RATE_CHANGE)
+	_REGISTER_CLK(esdhc1_sel, &clk_mux_ops, 0)
+	_REGISTER_CLK(esdhc1_pred, &clk_divider_ops, 0)
+	_REGISTER_CLK(esdhc1_podf, &clk_divider_ops, HINT_PARENT_RATE_CHANGE)
+	_REGISTER_CLK(esdhc2_sel, &clk_mux_ops, 0)
+	_REGISTER_CLK(esdhc2_pred, &clk_divider_ops, 0)
+	_REGISTER_CLK(esdhc2_podf, &clk_divider_ops, HINT_PARENT_RATE_CHANGE)
+	_REGISTER_CLK(esdhc3_sel, &clk_mux_ops, 0)
+	_REGISTER_CLK(esdhc4_sel, &clk_mux_ops, 0)
+	_REGISTER_CLK(emi_sel, &clk_mux_ops, 0)
+	_REGISTER_CLK(emi_slow_podf, &clk_divider_ops, 0)
+	_REGISTER_CLK(nfc_podf, &clk_divider_ops, 0)
+	_REGISTER_CLK(ssi_lp_apm, &clk_mux_ops, 0)
+	_REGISTER_CLK(ssi1_clk_sel, &clk_mux_ops, 0)
+	_REGISTER_CLK(ssi1_clk_pred, &clk_divider_ops, 0)
+	_REGISTER_CLK(ssi1_clk, &clk_divider_ops, HINT_PARENT_RATE_CHANGE)
+	_REGISTER_CLK(ssi2_clk_sel, &clk_mux_ops, 0)
+	_REGISTER_CLK(ssi2_clk_pred, &clk_divider_ops, 0)
+	_REGISTER_CLK(ssi2_clk, &clk_divider_ops, HINT_PARENT_RATE_CHANGE)
+	_REGISTER_CLK(ssi3_clk, &clk_mux_ops, 0)
+	_REGISTER_CLK(ecspi_sel, &clk_mux_ops, 0)
+	_REGISTER_CLK(ecspi_pred, &clk_divider_ops, 0)
+	_REGISTER_CLK(ecspi_podf, &clk_divider_ops, HINT_PARENT_RATE_CHANGE)
+	_REGISTER_CLK(usboh3_sel, &clk_mux_ops, 0)
+	_REGISTER_CLK(usboh3_pred, &clk_divider_ops, 0)
+	_REGISTER_CLK(usboh3_podf, &clk_divider_ops, HINT_PARENT_RATE_CHANGE)
+	_REGISTER_CLK(usb_phy_pred, &clk_divider_ops, 0)
+	_REGISTER_CLK(usb_phy_podf, &clk_divider_ops, HINT_PARENT_RATE_CHANGE)
+	_REGISTER_CLK(usb_phy_sel, &clk_mux_ops, 0)
+	_REGISTER_CLK(cpu_podf, &clk_divider_ops, 0)
+	_REGISTER_CLK(ipu_di0_sel, &clk_mux_ops, 0)
+	_REGISTER_CLK(ipu_di1_sel, &clk_mux_ops, 0)
+	_REGISTER_CLK(tve_ext_sel, &clk_mux_ops, 0)
+	_REGISTER_CLK(tve_pred, &clk_divider_ops, 0)
+	_REGISTER_CLK(tve_sel, &clk_mux_ops, 0)
+	_REGISTER_CLK(ahbmux1, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(aips_tz1, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(aips_tz2, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(ahb_max, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(iim_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(uart1_ipg_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(uart1_per_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(uart2_ipg_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(uart2_per_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(uart3_ipg_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(uart3_per_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(i2c1_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(i2c2_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(gpt_ipg_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(pwm1_ipg_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(pwm1_hf_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(pwm2_ipg_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(pwm2_hf_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(gpt_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(fec_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(usboh3_ahb_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(usboh3_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(tve_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(esdhc1_ipg_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(esdhc1_per_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(esdhc2_ipg_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(esdhc2_per_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(esdhc3_ipg_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(esdhc3_per_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(esdhc4_ipg_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(esdhc4_per_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(ssi1_ipg_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(ssi1_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(ssi2_ipg_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(ssi2_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(ssi3_ipg_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(ssi3_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(ecspi1_ipg_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(ecspi1_per_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(ecspi2_ipg_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(ecspi2_per_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(cspi_ipg_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(sdma_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(ipu_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(emi_fast_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(emi_slow_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(nfc_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(ipu_di0_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(ipu_di1_gate, &clk_gate2b_ops, 0)
+};
+
+struct clk *mx51_clk_array[] = {
+	_REGISTER_CLK(ddr_hf_mx51, &clk_divider_ops, 0)
+	_REGISTER_CLK(ddr_root_mx51, &clk_mux_ops, 0)
+	_REGISTER_CLK(hsi2c_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(mx51_usb_phy_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(mx51_mipi_hsc1_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(mx51_mipi_hsc2_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(mx51_mipi_esc_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(mx51_mipi_hsp_gate, &clk_gate2b_ops, 0)
+};
+
+struct clk *mx53_clk_array[] = {
+	_REGISTER_CLK(mx53_usb_phy1_gate, &clk_gate2b_ops, 0)
+	_REGISTER_CLK(mx53_usb_phy2_gate, &clk_gate2b_ops, 0)
+};
+
+static void clk_register_array(struct clk **clks, int num)
+{
+	int i;
+
+	for (i = 0; i < num; i++)
+		clk_init(NULL, clks[i]);
+}
+
+static void clkdev_add_array(struct clk_lookup *lookup, int num)
+{
+	int i;
+
+	for (i = 0; i < num; i++)
+		clkdev_add(&lookup[i]);
+}
+
+static void mx5_clocks_common_init(unsigned long rate_ckil, unsigned long rate_osc,
+			unsigned long rate_ckih1, unsigned long rate_ckih2)
+{
+	int i;
+
+	ckil.fixed_rate = rate_ckil;
+	osc.fixed_rate = rate_osc;
+	ckih1.fixed_rate = rate_ckih1;
+	ckih2.fixed_rate = rate_ckih2;
+
+	clk_register_array(mx5_clk_array, ARRAY_SIZE(mx5_clk_array));
+	clkdev_add_array(mx5_lookups, ARRAY_SIZE(mx5_lookups));
+
+	/* Set SDHC parents to be PLL2 */
+	clk_set_parent(&esdhc1_sel.clk, &pll2_sw.clk);
+	clk_set_parent(&esdhc2_sel.clk, &pll2_sw.clk);
+
+	/* keep device ipg clocks on until drivers handle it */
+	for (i = 0; i < ARRAY_SIZE(mx5_on_clocks); i++) {
+		clk_prepare(mx5_on_clocks[i]);
+		clk_enable(mx5_on_clocks[i]);
+	}
+}
+
+int __init mx53_clocks_init(unsigned long rate_ckil, unsigned long rate_osc,
+			unsigned long rate_ckih1, unsigned long rate_ckih2)
+{
+	/* Clock tree has i.MX51 layout. i.MX53 needs some fixups */
+	pll1.base = MX53_DPLL1_BASE;
+	pll2.base = MX53_DPLL2_BASE;
+	pll3.base = MX53_DPLL3_BASE;
+	esdhc3_per_gate.clk.parent = &esdhc2_podf.clk;
+	esdhc2_per_gate.clk.parent = &esdhc3_sel.clk;
+	tve_gate.clk.parent = &tve_pred.clk;
+	tve_pred.clk.parent = &tve_ext_sel.clk;
+	tve_ext_sel_clks[0] = &pll4_sw.clk;
+	tve_ext_sel_clks[1] = &ckih1.clk;
+
+	mx5_clocks_common_init(rate_ckil, rate_osc, rate_ckih1, rate_ckih2);
+	clk_register_array(mx53_clk_array, ARRAY_SIZE(mx53_clk_array));
+	clkdev_add_array(mx53_lookups, ARRAY_SIZE(mx53_lookups));
+
+	/* set SDHC root clock to 200MHZ*/
+	clk_set_rate(&esdhc1_podf.clk, 200000000);
+	clk_set_rate(&esdhc2_podf.clk, 200000000);
+
+	/* System timer */
+	mxc_timer_init(&gpt_gate.clk, MX53_IO_ADDRESS(MX53_GPT1_BASE_ADDR),
+		MX53_INT_GPT);
+
+	clk_prepare(&iim_gate.clk);
+	clk_enable(&iim_gate.clk);
+	imx_print_silicon_rev("i.MX53", mx53_revision());
+	clk_disable(&iim_gate.clk);
+	clk_unprepare(&iim_gate.clk);
+
+	return 0;
+}
+
+int __init mx51_clocks_init(unsigned long rate_ckil, unsigned long rate_osc,
+			unsigned long rate_ckih1, unsigned long rate_ckih2)
+{
+	mx5_clocks_common_init(rate_ckil, rate_osc, rate_ckih1, rate_ckih2);
+	clk_register_array(mx51_clk_array, ARRAY_SIZE(mx5_clk_array));
+	clkdev_add_array(mx51_lookups, ARRAY_SIZE(mx51_lookups));
+
+	/* set SDHC root clock to 166.25MHZ*/
+	clk_set_rate(&esdhc1_podf.clk, 166250000);
+	clk_set_rate(&esdhc2_podf.clk, 166250000);
+
+	/* System timer */
+	mxc_timer_init(&gpt_gate.clk, MX51_IO_ADDRESS(MX51_GPT1_BASE_ADDR),
+		MX51_INT_GPT);
+
+	clk_prepare(&iim_gate.clk);
+	clk_enable(&iim_gate.clk);
+	imx_print_silicon_rev("i.MX51", mx51_revision());
+	clk_disable(&iim_gate.clk);
+
+	return 0;
+}
diff --git a/arch/arm/plat-mxc/include/mach/clock.h b/arch/arm/plat-mxc/include/mach/clock.h
index 500879b..e30e8fa 100644
--- a/arch/arm/plat-mxc/include/mach/clock.h
+++ b/arch/arm/plat-mxc/include/mach/clock.h
@@ -26,6 +26,8 @@ 
 #ifndef CONFIG_GENERIC_CLK
 struct module;
 
+#ifdef CONFIG_USE_COMMON_STRUCT_CLK
+#else
 struct clk {
 	int id;
 	/* Source clock this clk depends on */
@@ -57,6 +59,7 @@  struct clk {
 	/* Function ptr to set the parent clock of the clock. */
 	int (*set_parent) (struct clk *, struct clk *);
 };
+#endif
 
 int clk_register(struct clk *clk);
 void clk_unregister(struct clk *clk);