[PATCH v6 1/5] clk: imx8m: Set CLK_GET_RATE_NOCACHE on dram clocks

Leonard Crestez
2019-11-14T18:34:05Z

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>
---
drivers/clk/imx/clk-imx8mm.c | 9 +++++++--
drivers/clk/imx/clk-imx8mn.c | 10 ++++++++--
drivers/clk/imx/clk-imx8mq.c | 12 ++++++++----
3 files changed, 23 insertions(+), 8 deletions(-)

diff --git a/drivers/clk/imx/clk-imx8mm.c b/drivers/clk/imx/clk-imx8mm.c
index 030b15d7c0ce..e2bc3c90d93c 100644
--- a/drivers/clk/imx/clk-imx8mm.c
+++ b/drivers/clk/imx/clk-imx8mm.c
@@ -440,13 +440,18 @@ static int imx8mm_clocks_probe(struct platform_device *pdev)

/* IPG */
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);
clks[IMX8MM_CLK_DISP_DC8000] = imx8m_clk_composite("disp_dc8000", imx8mm_disp_dc8000_sels, base + 0xa280);
clks[IMX8MM_CLK_PCIE1_CTRL] = imx8m_clk_composite("pcie1_ctrl", imx8mm_pcie1_ctrl_sels, base + 0xa300);
diff --git a/drivers/clk/imx/clk-imx8mn.c b/drivers/clk/imx/clk-imx8mn.c
index 9f5a5a56b45e..de905e278b80 100644
--- a/drivers/clk/imx/clk-imx8mn.c
+++ b/drivers/clk/imx/clk-imx8mn.c
@@ -428,12 +428,18 @@ static int imx8mn_clocks_probe(struct platform_device *pdev)
clks[IMX8MN_CLK_AHB] = imx8m_clk_composite_critical("ahb", imx8mn_ahb_sels, base + 0x9000);
clks[IMX8MN_CLK_AUDIO_AHB] = imx8m_clk_composite("audio_ahb", imx8mn_audio_ahb_sels, base + 0x9100);
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);
clks[IMX8MN_CLK_SAI5] = imx8m_clk_composite("sai5", imx8mn_sai5_sels, base + 0xa780);
clks[IMX8MN_CLK_SAI6] = imx8m_clk_composite("sai6", imx8mn_sai6_sels, base + 0xa800);
diff --git a/drivers/clk/imx/clk-imx8mq.c b/drivers/clk/imx/clk-imx8mq.c
index 5f10a606d836..c8ab86fcba7c 100644
--- a/drivers/clk/imx/clk-imx8mq.c
+++ b/drivers/clk/imx/clk-imx8mq.c
@@ -341,11 +341,11 @@ static int imx8mq_clocks_probe(struct platform_device *pdev)
clks[IMX8MQ_VIDEO_PLL1_OUT] = imx_clk_gate("video_pll1_out", "video_pll1_bypass", base + 0x10, 21);

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 */
clks[IMX8MQ_SYS1_PLL_40M_CG] = imx_clk_gate("sys1_pll_40m_cg", "sys1_pll_out", base + 0x30, 9);
clks[IMX8MQ_SYS1_PLL_80M_CG] = imx_clk_gate("sys1_pll_80m_cg", "sys1_pll_out", base + 0x30, 11);
@@ -433,15 +433,19 @@ static int imx8mq_clocks_probe(struct platform_device *pdev)

/* IPG */
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);
clks[IMX8MQ_CLK_DISP_DC8000] = imx8m_clk_composite("disp_dc8000", imx8mq_disp_dc8000_sels, base + 0xa280);
clks[IMX8MQ_CLK_PCIE1_CTRL] = imx8m_clk_composite("pcie1_ctrl", imx8mq_pcie1_ctrl_sels, base + 0xa300);