clk: imx8mq: add PLL monitor output

The PLL monitor is mentioned as a debug feature in the reference manual,
but there are some boards that use this clock output as a reference clock
for board level components. Add support for those clocks in the clock
driver, so this clock output can be used properly.

Note that the VIDEO1, GPU and VPU mux inputs are rotated compared to the
description in the reference manual. The order in this patch has been
empirically validated.

Signed-off-by: Lucas Stach <[e-mail]>
Reviewed-by: Abel Vesa <[e-mail]>
Signed-off-by: Shawn Guo <[e-mail]>

drivers/clk/imx/clk-imx8mq.c

···
 static const char * const imx8mq_clko2_sels[] = {"osc_25m", "sys2_pll_200m", "sys1_pll_400m", "sys2_pll_166m",
 					  "sys3_pll_out", "audio_pll1_out", "video_pll1_out", "ckil", };
 
+static const char * const pllout_monitor_sels[] = {"osc_25m", "osc_27m", "dummy", "dummy", "ckil",
+						   "audio_pll1_out_monitor", "audio_pll2_out_monitor",
+						   "video_pll1_out_monitor", "gpu_pll_out_monitor",
+						   "vpu_pll_out_monitor", "arm_pll_out_monitor",
+						   "sys_pll1_out_monitor", "sys_pll2_out_monitor",
+						   "sys_pll3_out_monitor", "dram_pll_out_monitor",
+						   "video_pll2_out_monitor", };
+
 static struct clk_hw_onecell_data *clk_hw_data;
 static struct clk_hw **hws;
 
···
 	hws[IMX8MQ_SYS2_PLL_333M] = imx_clk_hw_fixed_factor("sys2_pll_333m", "sys2_pll_333m_cg", 1, 3);
 	hws[IMX8MQ_SYS2_PLL_500M] = imx_clk_hw_fixed_factor("sys2_pll_500m", "sys2_pll_500m_cg", 1, 2);
 	hws[IMX8MQ_SYS2_PLL_1000M] = imx_clk_hw_fixed_factor("sys2_pll_1000m", "sys2_pll_1000m_cg", 1, 1);
+
+	hws[IMX8MQ_CLK_MON_AUDIO_PLL1_DIV] = imx_clk_hw_divider("audio_pll1_out_monitor", "audio_pll1_bypass", base + 0x78, 0, 3);
+	hws[IMX8MQ_CLK_MON_AUDIO_PLL2_DIV] = imx_clk_hw_divider("audio_pll2_out_monitor", "audio_pll2_bypass", base + 0x78, 4, 3);
+	hws[IMX8MQ_CLK_MON_VIDEO_PLL1_DIV] = imx_clk_hw_divider("video_pll1_out_monitor", "video_pll1_bypass", base + 0x78, 8, 3);
+	hws[IMX8MQ_CLK_MON_GPU_PLL_DIV] = imx_clk_hw_divider("gpu_pll_out_monitor", "gpu_pll_bypass", base + 0x78, 12, 3);
+	hws[IMX8MQ_CLK_MON_VPU_PLL_DIV] = imx_clk_hw_divider("vpu_pll_out_monitor", "vpu_pll_bypass", base + 0x78, 16, 3);
+	hws[IMX8MQ_CLK_MON_ARM_PLL_DIV] = imx_clk_hw_divider("arm_pll_out_monitor", "arm_pll_bypass", base + 0x78, 20, 3);
+	hws[IMX8MQ_CLK_MON_SYS_PLL1_DIV] = imx_clk_hw_divider("sys_pll1_out_monitor", "sys1_pll_out", base + 0x7c, 0, 3);
+	hws[IMX8MQ_CLK_MON_SYS_PLL2_DIV] = imx_clk_hw_divider("sys_pll2_out_monitor", "sys2_pll_out", base + 0x7c, 4, 3);
+	hws[IMX8MQ_CLK_MON_SYS_PLL3_DIV] = imx_clk_hw_divider("sys_pll3_out_monitor", "sys3_pll_out", base + 0x7c, 8, 3);
+	hws[IMX8MQ_CLK_MON_DRAM_PLL_DIV] = imx_clk_hw_divider("dram_pll_out_monitor", "dram_pll_out", base + 0x7c, 12, 3);
+	hws[IMX8MQ_CLK_MON_VIDEO_PLL2_DIV] = imx_clk_hw_divider("video_pll2_out_monitor", "video2_pll_out", base + 0x7c, 16, 3);
+	hws[IMX8MQ_CLK_MON_SEL] = imx_clk_hw_mux("pllout_monitor_sel", base + 0x74, 0, 4, pllout_monitor_sels, ARRAY_SIZE(pllout_monitor_sels));
+	hws[IMX8MQ_CLK_MON_CLK2_OUT] = imx_clk_hw_gate("pllout_monitor_clk2", "pllout_monitor_sel", base + 0x74, 4);
 
 	np = dev->of_node;
 	base = devm_platform_ioremap_resource(pdev, 0);

include/dt-bindings/clock/imx8mq-clock.h

···
 
 #define IMX8MQ_CLK_A53_CORE			289
 
-#define IMX8MQ_CLK_END				290
+#define IMX8MQ_CLK_MON_AUDIO_PLL1_DIV		290
+#define IMX8MQ_CLK_MON_AUDIO_PLL2_DIV		291
+#define IMX8MQ_CLK_MON_VIDEO_PLL1_DIV		292
+#define IMX8MQ_CLK_MON_GPU_PLL_DIV		293
+#define IMX8MQ_CLK_MON_VPU_PLL_DIV		294
+#define IMX8MQ_CLK_MON_ARM_PLL_DIV		295
+#define IMX8MQ_CLK_MON_SYS_PLL1_DIV		296
+#define IMX8MQ_CLK_MON_SYS_PLL2_DIV		297
+#define IMX8MQ_CLK_MON_SYS_PLL3_DIV		298
+#define IMX8MQ_CLK_MON_DRAM_PLL_DIV		299
+#define IMX8MQ_CLK_MON_VIDEO_PLL2_DIV		300
+#define IMX8MQ_CLK_MON_SEL			301
+#define IMX8MQ_CLK_MON_CLK2_OUT			302
+
+#define IMX8MQ_CLK_END				303
 
 #endif /* __DT_BINDINGS_CLOCK_IMX8MQ_H */