clk: imx8m: Set CLK_GET_RATE_NOCACHE on dram clocks

These clocks are only modified as part of DRAM frequency switches during
which DRAM itself is briefly inaccessible. The switch is performed with
a SMC call to by TF-A which runs from a SRAM area; upon returning to
linux several clocks bits are modified and we need to update them.

For rate bits an easy solution is to just mark with
CLK_GET_RATE_NOCACHE so that new rates are always read back from
registers.
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Reviewed-by: Abel Vesa <abel.vesa@nxp.com>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

drivers/clk/imx/clk-imx8mm.c

@@ -442,9 +442,14 @@ static int imx8mm_clocks_probe(struct platform_device *pdev)
 	clks[IMX8MM_CLK_IPG_ROOT] = imx_clk_divider2("ipg_root", "ahb", base + 0x9080, 0, 1);
 	clks[IMX8MM_CLK_IPG_AUDIO_ROOT] = imx_clk_divider2("ipg_audio_root", "audio_ahb", base + 0x9180, 0, 1);
 
+	/*
+	 * DRAM clocks are manipulated from TF-A outside clock framework.
+	 * Mark with GET_RATE_NOCACHE to always read div value from hardware
+	 */
+	clks[IMX8MM_CLK_DRAM_ALT] = __imx8m_clk_composite("dram_alt", imx8mm_dram_alt_sels, base + 0xa000, CLK_GET_RATE_NOCACHE);
+	clks[IMX8MM_CLK_DRAM_APB] = __imx8m_clk_composite("dram_apb", imx8mm_dram_apb_sels, base + 0xa080, CLK_IS_CRITICAL | CLK_GET_RATE_NOCACHE);
+
 	/* IP */
-	clks[IMX8MM_CLK_DRAM_ALT] = imx8m_clk_composite("dram_alt", imx8mm_dram_alt_sels, base + 0xa000);
-	clks[IMX8MM_CLK_DRAM_APB] = imx8m_clk_composite_critical("dram_apb", imx8mm_dram_apb_sels, base + 0xa080);
 	clks[IMX8MM_CLK_VPU_G1] = imx8m_clk_composite("vpu_g1", imx8mm_vpu_g1_sels, base + 0xa100);
 	clks[IMX8MM_CLK_VPU_G2] = imx8m_clk_composite("vpu_g2", imx8mm_vpu_g2_sels, base + 0xa180);
 	clks[IMX8MM_CLK_DISP_DTRC] = imx8m_clk_composite("disp_dtrc", imx8mm_disp_dtrc_sels, base + 0xa200);

drivers/clk/imx/clk-imx8mn.c

@@ -430,8 +430,14 @@ static int imx8mn_clocks_probe(struct platform_device *pdev)
 	clks[IMX8MN_CLK_IPG_ROOT] = imx_clk_divider2("ipg_root", "ahb", base + 0x9080, 0, 1);
 	clks[IMX8MN_CLK_IPG_AUDIO_ROOT] = imx_clk_divider2("ipg_audio_root", "audio_ahb", base + 0x9180, 0, 1);
 	clks[IMX8MN_CLK_DRAM_CORE] = imx_clk_mux2_flags("dram_core_clk", base + 0x9800, 24, 1, imx8mn_dram_core_sels, ARRAY_SIZE(imx8mn_dram_core_sels), CLK_IS_CRITICAL);
-	clks[IMX8MN_CLK_DRAM_ALT] = imx8m_clk_composite("dram_alt", imx8mn_dram_alt_sels, base + 0xa000);
-	clks[IMX8MN_CLK_DRAM_APB] = imx8m_clk_composite_critical("dram_apb", imx8mn_dram_apb_sels, base + 0xa080);
+
+	/*
+	 * DRAM clocks are manipulated from TF-A outside clock framework.
+	 * Mark with GET_RATE_NOCACHE to always read div value from hardware
+	 */
+	clks[IMX8MN_CLK_DRAM_ALT] = __imx8m_clk_composite("dram_alt", imx8mn_dram_alt_sels, base + 0xa000, CLK_GET_RATE_NOCACHE);
+	clks[IMX8MN_CLK_DRAM_APB] = __imx8m_clk_composite("dram_apb", imx8mn_dram_apb_sels, base + 0xa080, CLK_IS_CRITICAL | CLK_GET_RATE_NOCACHE);
+
 	clks[IMX8MN_CLK_DISP_PIXEL] = imx8m_clk_composite("disp_pixel", imx8mn_disp_pixel_sels, base + 0xa500);
 	clks[IMX8MN_CLK_SAI2] = imx8m_clk_composite("sai2", imx8mn_sai2_sels, base + 0xa600);
 	clks[IMX8MN_CLK_SAI3] = imx8m_clk_composite("sai3", imx8mn_sai3_sels, base + 0xa680);

drivers/clk/imx/clk-imx8mq.c

@@ -343,7 +343,7 @@ static int imx8mq_clocks_probe(struct platform_device *pdev)
 	clks[IMX8MQ_SYS1_PLL_OUT] = imx_clk_fixed("sys1_pll_out", 800000000);
 	clks[IMX8MQ_SYS2_PLL_OUT] = imx_clk_fixed("sys2_pll_out", 1000000000);
 	clks[IMX8MQ_SYS3_PLL_OUT] = imx_clk_sccg_pll("sys3_pll_out", sys3_pll_out_sels, ARRAY_SIZE(sys3_pll_out_sels), 0, 0, 0, base + 0x48, CLK_IS_CRITICAL);
-	clks[IMX8MQ_DRAM_PLL_OUT] = imx_clk_sccg_pll("dram_pll_out", dram_pll_out_sels, ARRAY_SIZE(dram_pll_out_sels), 0, 0, 0, base + 0x60, CLK_IS_CRITICAL);
+	clks[IMX8MQ_DRAM_PLL_OUT] = imx_clk_sccg_pll("dram_pll_out", dram_pll_out_sels, ARRAY_SIZE(dram_pll_out_sels), 0, 0, 0, base + 0x60, CLK_IS_CRITICAL | CLK_GET_RATE_NOCACHE);
 	clks[IMX8MQ_VIDEO2_PLL_OUT] = imx_clk_sccg_pll("video2_pll_out", video2_pll_out_sels, ARRAY_SIZE(video2_pll_out_sels), 0, 0, 0, base + 0x54, 0);
 
 	/* SYS PLL1 fixed output */
@@ -435,11 +435,15 @@ static int imx8mq_clocks_probe(struct platform_device *pdev)
 	clks[IMX8MQ_CLK_IPG_ROOT] = imx_clk_divider2("ipg_root", "ahb", base + 0x9080, 0, 1);
 	clks[IMX8MQ_CLK_IPG_AUDIO_ROOT] = imx_clk_divider2("ipg_audio_root", "audio_ahb", base + 0x9180, 0, 1);
 
-	/* IP */
+	/*
+	 * DRAM clocks are manipulated from TF-A outside clock framework.
+	 * Mark with GET_RATE_NOCACHE to always read div value from hardware
+	 */
 	clks[IMX8MQ_CLK_DRAM_CORE] = imx_clk_mux2_flags("dram_core_clk", base + 0x9800, 24, 1, imx8mq_dram_core_sels, ARRAY_SIZE(imx8mq_dram_core_sels), CLK_IS_CRITICAL);
+	clks[IMX8MQ_CLK_DRAM_ALT] = __imx8m_clk_composite("dram_alt", imx8mq_dram_alt_sels, base + 0xa000, CLK_GET_RATE_NOCACHE);
+	clks[IMX8MQ_CLK_DRAM_APB] = __imx8m_clk_composite("dram_apb", imx8mq_dram_apb_sels, base + 0xa080, CLK_IS_CRITICAL | CLK_GET_RATE_NOCACHE);
 
-	clks[IMX8MQ_CLK_DRAM_ALT] = imx8m_clk_composite("dram_alt", imx8mq_dram_alt_sels, base + 0xa000);
-	clks[IMX8MQ_CLK_DRAM_APB] = imx8m_clk_composite_critical("dram_apb", imx8mq_dram_apb_sels, base + 0xa080);
+	/* IP */
 	clks[IMX8MQ_CLK_VPU_G1] = imx8m_clk_composite("vpu_g1", imx8mq_vpu_g1_sels, base + 0xa100);
 	clks[IMX8MQ_CLK_VPU_G2] = imx8m_clk_composite("vpu_g2", imx8mq_vpu_g2_sels, base + 0xa180);
 	clks[IMX8MQ_CLK_DISP_DTRC] = imx8m_clk_composite("disp_dtrc", imx8mq_disp_dtrc_sels, base + 0xa200);