ARM: imx: add gpt_3m clk for i.mx6qdl

Add gpt_3m clock for i.mx6qdl, as gpt can source clock
from OSC, some i.MX6 series SOCs has fixed divider of
8 for gpt clock, so here add a fix clk of gpt_3m.

i.MX6Q TO1.0 has no gpt_3m option, so force it to be
from ipg_per.

Signed-off-by: Anson Huang <b20788@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@freescale.com>

arch/arm/mach-imx/clk-imx6q.c

@@ -245,6 +245,7 @@ static void __init imx6q_clocks_init(struct device_node *ccm_node)
 	clk[IMX6QDL_CLK_PLL3_80M]  = imx_clk_fixed_factor("pll3_80m",  "pll3_usb_otg",   1, 6);
 	clk[IMX6QDL_CLK_PLL3_60M]  = imx_clk_fixed_factor("pll3_60m",  "pll3_usb_otg",   1, 8);
 	clk[IMX6QDL_CLK_TWD]       = imx_clk_fixed_factor("twd",       "arm",            1, 2);
+	clk[IMX6QDL_CLK_GPT_3M]    = imx_clk_fixed_factor("gpt_3m",    "osc",            1, 8);
 	if (cpu_is_imx6dl()) {
 		clk[IMX6QDL_CLK_GPU2D_AXI] = imx_clk_fixed_factor("gpu2d_axi", "mmdc_ch0_axi_podf", 1, 1);
 		clk[IMX6QDL_CLK_GPU3D_AXI] = imx_clk_fixed_factor("gpu3d_axi", "mmdc_ch0_axi_podf", 1, 1);
@@ -461,6 +462,13 @@ static void __init imx6q_clocks_init(struct device_node *ccm_node)
 	clk[IMX6QDL_CLK_CKO1]         = imx_clk_gate("cko1",           "cko1_podf",         base + 0x60, 7);
 	clk[IMX6QDL_CLK_CKO2]         = imx_clk_gate("cko2",           "cko2_podf",         base + 0x60, 24);
 
+	/*
+	 * The gpt_3m clock is not available on i.MX6Q TO1.0.  Let's point it
+	 * to clock gpt_ipg_per to ease the gpt driver code.
+	 */
+	if (cpu_is_imx6q() && imx_get_soc_revision() == IMX_CHIP_REVISION_1_0)
+		clk[IMX6QDL_CLK_GPT_3M] = clk[IMX6QDL_CLK_GPT_IPG_PER];
+
 	imx_check_clocks(clk, ARRAY_SIZE(clk));
 
 	clk_data.clks = clk;

include/dt-bindings/clock/imx6qdl-clock.h

@@ -247,6 +247,7 @@
 #define IMX6QDL_PLL5_BYPASS			234
 #define IMX6QDL_PLL6_BYPASS			235
 #define IMX6QDL_PLL7_BYPASS			236
-#define IMX6QDL_CLK_END				237
+#define IMX6QDL_CLK_GPT_3M			237
+#define IMX6QDL_CLK_END				238
 
 #endif /* __DT_BINDINGS_CLOCK_IMX6QDL_H */