sugar/linux
1
0
Fork 0
Code Activity

clk: imx95-blk-ctl: Save/restore registers when RPM routines are called

Browse Source 
When runtime PM is used for clock providers that are part of a power
domain, the power domain supply is cut off during runtime suspend. This
causes all BLK CTL registers belonging to that power domain to reset. To
prevent this, save the state of the registers before entering suspend
and restore them on resume. Additionally, disable the APB clock during
suspend to minimize power consumption.

Signed-off-by: Laurentiu Palcu <laurentiu.palcu@oss.nxp.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Link: https://lore.kernel.org/r/20250804131450.3918846-3-laurentiu.palcu@oss.nxp.com
Signed-off-by: Abel Vesa <abel.vesa@linaro.org>
This commit is contained in:
Laurentiu Palcu
2025-08-04 16:14:50 +03:00
committed by Abel Vesa
parent aa1735d72b
commit 14be8b7b6c
1 changed files with 21 additions and 12 deletions
Download Patch File Download Diff File Expand all files Collapse all files

33
drivers/clk/imx/clk-imx95-blk-ctl.c
View File

@@ -453,15 +453,24 @@ static int imx95_bc_runtime_suspend(struct device *dev)
{
struct imx95_blk_ctl *bc = dev_get_drvdata(dev);
bc->clk_reg_restore = readl(bc->base + bc->pdata->clk_reg_offset);
clk_disable_unprepare(bc->clk_apb);
return 0;
}
static int imx95_bc_runtime_resume(struct device *dev)
{
struct imx95_blk_ctl *bc = dev_get_drvdata(dev);
int ret;
return clk_prepare_enable(bc->clk_apb);
ret = clk_prepare_enable(bc->clk_apb);
if (ret)
return ret;
writel(bc->clk_reg_restore, bc->base + bc->pdata->clk_reg_offset);
return 0;
}
#endif
@@ -469,17 +478,12 @@ static int imx95_bc_runtime_resume(struct device *dev)
static int imx95_bc_suspend(struct device *dev)
{
struct imx95_blk_ctl *bc = dev_get_drvdata(dev);
int ret;
if (bc->pdata->rpm_enabled) {
ret = pm_runtime_get_sync(bc->dev);
if (ret < 0) {
pm_runtime_put_noidle(bc->dev);
return ret;
}
}
if (pm_runtime_suspended(dev))
return 0;
bc->clk_reg_restore = readl(bc->base + bc->pdata->clk_reg_offset);
clk_disable_unprepare(bc->clk_apb);
return 0;
}
@@ -487,12 +491,17 @@ static int imx95_bc_suspend(struct device *dev)
static int imx95_bc_resume(struct device *dev)
{
struct imx95_blk_ctl *bc = dev_get_drvdata(dev);
int ret;
if (pm_runtime_suspended(dev))
return 0;
ret = clk_prepare_enable(bc->clk_apb);
if (ret)
return ret;
writel(bc->clk_reg_restore, bc->base + bc->pdata->clk_reg_offset);
if (bc->pdata->rpm_enabled)
pm_runtime_put(bc->dev);
return 0;
}
#endif