iommu: msm: Add support for alt_core_clk for IOMMU
Some of the IOMMUs might require an extra clock to allow programming
of the IOMMU registers. Add support for an alternative core clock so
that the correct clocks can be enabled before accessing IOMMU
registers.
Change-Id: Ie79fcf7ddca0080c6938f0d28eea61a6c33b949c
Signed-off-by: Olav Haugan <ohaugan@codeaurora.org>
diff --git a/drivers/iommu/msm_iommu_dev-v0.c b/drivers/iommu/msm_iommu_dev-v0.c
index 7ae0b21..059216e 100644
--- a/drivers/iommu/msm_iommu_dev-v0.c
+++ b/drivers/iommu/msm_iommu_dev-v0.c
@@ -129,7 +129,8 @@
}
static int msm_iommu_parse_dt(struct platform_device *pdev,
- struct msm_iommu_drvdata *drvdata)
+ struct msm_iommu_drvdata *drvdata,
+ int *needs_alt_core_clk)
{
#ifdef CONFIG_OF_DEVICE
struct device_node *child;
@@ -169,6 +170,10 @@
pr_err("%s: Missing property label\n", __func__);
return -EINVAL;
}
+
+ *needs_alt_core_clk = of_property_read_bool(pdev->dev.of_node,
+ "qcom,needs-alt-core-clk");
+
drvdata->sec_id = -1;
drvdata->ttbr_split = 0;
#endif
@@ -176,7 +181,8 @@
}
static int __get_clocks(struct platform_device *pdev,
- struct msm_iommu_drvdata *drvdata)
+ struct msm_iommu_drvdata *drvdata,
+ int needs_alt_core_clk)
{
int ret = 0;
@@ -199,6 +205,18 @@
} else {
drvdata->clk = NULL;
}
+
+ if (needs_alt_core_clk) {
+ drvdata->aclk = devm_clk_get(&pdev->dev, "alt_core_clk");
+ if (IS_ERR(drvdata->aclk))
+ return PTR_ERR(drvdata->aclk);
+ }
+
+ if (drvdata->aclk && clk_get_rate(drvdata->aclk) == 0) {
+ ret = clk_round_rate(drvdata->aclk, 1000);
+ clk_set_rate(drvdata->aclk, ret);
+ }
+
return 0;
fail:
return ret;
@@ -206,35 +224,13 @@
static void __put_clocks(struct msm_iommu_drvdata *drvdata)
{
+ if (drvdata->aclk)
+ clk_put(drvdata->aclk);
if (drvdata->clk)
clk_put(drvdata->clk);
clk_put(drvdata->pclk);
}
-static int __enable_clocks(struct msm_iommu_drvdata *drvdata)
-{
- int ret;
-
- ret = clk_prepare_enable(drvdata->pclk);
- if (ret)
- goto fail;
-
- if (drvdata->clk) {
- ret = clk_prepare_enable(drvdata->clk);
- if (ret)
- clk_disable_unprepare(drvdata->pclk);
- }
-fail:
- return ret;
-}
-
-static void __disable_clocks(struct msm_iommu_drvdata *drvdata)
-{
- if (drvdata->clk)
- clk_disable_unprepare(drvdata->clk);
- clk_disable_unprepare(drvdata->pclk);
-}
-
/*
* Do a basic check of the IOMMU by performing an ATS operation
* on context bank 0.
@@ -326,6 +322,7 @@
struct msm_iommu_drvdata *drvdata;
struct msm_iommu_dev *iommu_dev = pdev->dev.platform_data;
int ret;
+ int needs_alt_core_clk = 0;
drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL);
@@ -335,7 +332,7 @@
}
if (pdev->dev.of_node) {
- ret = msm_iommu_parse_dt(pdev, drvdata);
+ ret = msm_iommu_parse_dt(pdev, drvdata, &needs_alt_core_clk);
if (ret)
goto fail;
} else if (pdev->dev.platform_data) {
@@ -382,12 +379,12 @@
drvdata->dev = &pdev->dev;
- ret = __get_clocks(pdev, drvdata);
+ ret = __get_clocks(pdev, drvdata, needs_alt_core_clk);
if (ret)
goto fail;
- __enable_clocks(drvdata);
+ iommu_access_ops_v0.iommu_clk_on(drvdata);
msm_iommu_reset(drvdata->base, drvdata->glb_base, drvdata->ncb);
@@ -401,7 +398,7 @@
msm_iommu_add_drv(drvdata);
platform_set_drvdata(pdev, drvdata);
- __disable_clocks(drvdata);
+ iommu_access_ops_v0.iommu_clk_off(drvdata);
pmon_info = msm_iommu_pm_alloc(&pdev->dev);
if (pmon_info != NULL) {
@@ -430,7 +427,7 @@
return 0;
fail_clk:
- __disable_clocks(drvdata);
+ iommu_access_ops_v0.iommu_clk_off(drvdata);
__put_clocks(drvdata);
fail:
return ret;
@@ -618,9 +615,9 @@
goto fail;
}
- __enable_clocks(drvdata);
+ iommu_access_ops_v0.iommu_clk_on(drvdata);
__program_m2v_tables(drvdata, ctx_drvdata);
- __disable_clocks(drvdata);
+ iommu_access_ops_v0.iommu_clk_off(drvdata);
dev_info(&pdev->dev, "context %s using bank %d\n", ctx_drvdata->name,
ctx_drvdata->num);