[PATCH 10/18] clk: imx: Remove CLK_SET_PARENT_GATE for DRAM mux for i.MX7D

Peng Fan (OSS) posted 18 patches 1 year, 7 months ago
There is a newer version of this series
[PATCH 10/18] clk: imx: Remove CLK_SET_PARENT_GATE for DRAM mux for i.MX7D
Posted by Peng Fan (OSS) 1 year, 7 months ago
From: Peng Fan <peng.fan@nxp.com>

For i.MX7D DRAM related mux clock, the clock source change should ONLY
be done done in low level asm code without accessing DRAM, and then
calling clk API to sync the HW clock status with clk tree, it should never
touch real clock source switch via clk API, so CLK_SET_PARENT_GATE flag
should NOT be added, otherwise, DRAM's clock parent will be disabled when
DRAM is active, and system will hang.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
---
 drivers/clk/imx/clk-imx7d.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/imx/clk-imx7d.c b/drivers/clk/imx/clk-imx7d.c
index 2b77d1fc7bb9..1e1296e74835 100644
--- a/drivers/clk/imx/clk-imx7d.c
+++ b/drivers/clk/imx/clk-imx7d.c
@@ -498,9 +498,9 @@ static void __init imx7d_clocks_init(struct device_node *ccm_node)
 	hws[IMX7D_ENET_AXI_ROOT_SRC] = imx_clk_hw_mux2_flags("enet_axi_src", base + 0x8900, 24, 3, enet_axi_sel, ARRAY_SIZE(enet_axi_sel), CLK_SET_PARENT_GATE);
 	hws[IMX7D_NAND_USDHC_BUS_ROOT_SRC] = imx_clk_hw_mux2_flags("nand_usdhc_src", base + 0x8980, 24, 3, nand_usdhc_bus_sel, ARRAY_SIZE(nand_usdhc_bus_sel), CLK_SET_PARENT_GATE);
 	hws[IMX7D_DRAM_PHYM_ROOT_SRC] = imx_clk_hw_mux2_flags("dram_phym_src", base + 0x9800, 24, 1, dram_phym_sel, ARRAY_SIZE(dram_phym_sel), CLK_SET_PARENT_GATE);
-	hws[IMX7D_DRAM_ROOT_SRC] = imx_clk_hw_mux2_flags("dram_src", base + 0x9880, 24, 1, dram_sel, ARRAY_SIZE(dram_sel), CLK_SET_PARENT_GATE);
+	hws[IMX7D_DRAM_ROOT_SRC] = imx_clk_hw_mux2("dram_src", base + 0x9880, 24, 1, dram_sel, ARRAY_SIZE(dram_sel));
 	hws[IMX7D_DRAM_PHYM_ALT_ROOT_SRC] = imx_clk_hw_mux2_flags("dram_phym_alt_src", base + 0xa000, 24, 3, dram_phym_alt_sel, ARRAY_SIZE(dram_phym_alt_sel), CLK_SET_PARENT_GATE);
-	hws[IMX7D_DRAM_ALT_ROOT_SRC]  = imx_clk_hw_mux2_flags("dram_alt_src", base + 0xa080, 24, 3, dram_alt_sel, ARRAY_SIZE(dram_alt_sel), CLK_SET_PARENT_GATE);
+	hws[IMX7D_DRAM_ALT_ROOT_SRC]  = imx_clk_hw_mux2("dram_alt_src", base + 0xa080, 24, 3, dram_alt_sel, ARRAY_SIZE(dram_alt_sel));
 	hws[IMX7D_USB_HSIC_ROOT_SRC] = imx_clk_hw_mux2_flags("usb_hsic_src", base + 0xa100, 24, 3, usb_hsic_sel, ARRAY_SIZE(usb_hsic_sel), CLK_SET_PARENT_GATE);
 	hws[IMX7D_PCIE_CTRL_ROOT_SRC] = imx_clk_hw_mux2_flags("pcie_ctrl_src", base + 0xa180, 24, 3, pcie_ctrl_sel, ARRAY_SIZE(pcie_ctrl_sel), CLK_SET_PARENT_GATE);
 	hws[IMX7D_PCIE_PHY_ROOT_SRC] = imx_clk_hw_mux2_flags("pcie_phy_src", base + 0xa200, 24, 3, pcie_phy_sel, ARRAY_SIZE(pcie_phy_sel), CLK_SET_PARENT_GATE);

-- 
2.37.1
Re: [PATCH 10/18] clk: imx: Remove CLK_SET_PARENT_GATE for DRAM mux for i.MX7D
Posted by Francesco Dolcini 1 year, 7 months ago
Hello Peng,

On Sat, May 04, 2024 at 08:49:03AM +0800, Peng Fan (OSS) wrote:
> From: Peng Fan <peng.fan@nxp.com>
> 
> For i.MX7D DRAM related mux clock, the clock source change should ONLY
> be done done in low level asm code without accessing DRAM, and then
> calling clk API to sync the HW clock status with clk tree, it should never
> touch real clock source switch via clk API, so CLK_SET_PARENT_GATE flag
> should NOT be added, otherwise, DRAM's clock parent will be disabled when
> DRAM is active, and system will hang.

From the description this is solving a system hang, but no fixes tag nor
cc stable.

Francesco