[PATCH v11 06/10] soc: mediatek: Add subsys clock control for bus protection

From: Weiyi Lu
Date: Thu Dec 19 2019 - 22:46:48 EST


Add subsys CG control flow before/after the bus protect control
due to bus protection need SMI bus relative CGs enabled to feedback
its ack.

Signed-off-by: Weiyi Lu <weiyi.lu@xxxxxxxxxxxx>
Reviewed-by: Nicolas Boichat <drinkcat@xxxxxxxxxxxx>
---
drivers/soc/mediatek/mtk-scpsys.c | 72 +++++++++++++++++++++++++++++++++++++--
1 file changed, 70 insertions(+), 2 deletions(-)

diff --git a/drivers/soc/mediatek/mtk-scpsys.c b/drivers/soc/mediatek/mtk-scpsys.c
index 763ca58..32be4b3 100644
--- a/drivers/soc/mediatek/mtk-scpsys.c
+++ b/drivers/soc/mediatek/mtk-scpsys.c
@@ -79,6 +79,7 @@
#define PWR_STATUS_WB BIT(27) /* MT7622 */

#define MAX_CLKS 3
+#define MAX_SUBSYS_CLKS 10

/**
* struct scp_domain_data - scp domain data for power on/off flow
@@ -88,6 +89,8 @@
* @sram_pdn_bits: The mask for sram power control bits.
* @sram_pdn_ack_bits: The mask for sram power control acked bits.
* @basic_clk_name: The basic clocks required by this power domain.
+ * @subsys_clk_prefix: The prefix name of the clocks need to be enabled
+ * before releasing bus protection.
* @caps: The flag for active wake-up action.
* @bp_table: The mask table for multiple step bus protection.
*/
@@ -98,6 +101,7 @@ struct scp_domain_data {
u32 sram_pdn_bits;
u32 sram_pdn_ack_bits;
const char *basic_clk_name[MAX_CLKS];
+ const char *subsys_clk_prefix;
u8 caps;
struct bus_prot bp_table[MAX_STEPS];
};
@@ -108,6 +112,7 @@ struct scp_domain {
struct generic_pm_domain genpd;
struct scp *scp;
struct clk *clk[MAX_CLKS];
+ struct clk *subsys_clk[MAX_SUBSYS_CLKS];
const struct scp_domain_data *data;
struct regulator *supply;
};
@@ -301,16 +306,22 @@ static int scpsys_power_on(struct generic_pm_domain *genpd)
val |= PWR_RST_B_BIT;
writel(val, ctl_addr);

- ret = scpsys_sram_enable(scpd, ctl_addr);
+ ret = scpsys_clk_enable(scpd->subsys_clk, MAX_SUBSYS_CLKS);
if (ret < 0)
goto err_pwr_ack;

+ ret = scpsys_sram_enable(scpd, ctl_addr);
+ if (ret < 0)
+ goto err_sram;
+
ret = scpsys_bus_protect_disable(scpd);
if (ret < 0)
- goto err_pwr_ack;
+ goto err_sram;

return 0;

+err_sram:
+ scpsys_clk_disable(scpd->subsys_clk, MAX_SUBSYS_CLKS);
err_pwr_ack:
scpsys_clk_disable(scpd->clk, MAX_CLKS);
err_clk:
@@ -337,6 +348,8 @@ static int scpsys_power_off(struct generic_pm_domain *genpd)
if (ret < 0)
goto out;

+ scpsys_clk_disable(scpd->subsys_clk, MAX_SUBSYS_CLKS);
+
/* subsys power off */
val = readl(ctl_addr);
val |= PWR_ISO_BIT;
@@ -374,6 +387,48 @@ static int scpsys_power_off(struct generic_pm_domain *genpd)
return ret;
}

+static int init_subsys_clks(struct platform_device *pdev,
+ const char *prefix, struct clk **clk)
+{
+ struct device_node *node = pdev->dev.of_node;
+ u32 prefix_len, sub_clk_cnt = 0;
+ struct property *prop;
+ const char *clk_name;
+
+ if (!node) {
+ dev_err(&pdev->dev, "Cannot find scpsys node: %ld\n",
+ PTR_ERR(node));
+ return PTR_ERR(node);
+ }
+
+ prefix_len = strlen(prefix);
+
+ of_property_for_each_string(node, "clock-names", prop, clk_name) {
+ if (!strncmp(clk_name, prefix, prefix_len) &&
+ (clk_name[prefix_len] == '-')) {
+ if (sub_clk_cnt >= MAX_SUBSYS_CLKS) {
+ dev_err(&pdev->dev,
+ "subsys clk out of range %d\n",
+ sub_clk_cnt);
+ return -ENOMEM;
+ }
+
+ clk[sub_clk_cnt] = devm_clk_get(&pdev->dev,
+ clk_name);
+
+ if (IS_ERR(clk[sub_clk_cnt])) {
+ dev_err(&pdev->dev,
+ "Subsys clk get fail %ld\n",
+ PTR_ERR(clk[sub_clk_cnt]));
+ return PTR_ERR(clk[sub_clk_cnt]);
+ }
+ sub_clk_cnt++;
+ }
+ }
+
+ return sub_clk_cnt;
+}
+
static int init_basic_clks(struct platform_device *pdev, struct clk **clk,
const char * const *name)
{
@@ -466,6 +521,7 @@ static struct scp *init_scp(struct platform_device *pdev,
struct scp_domain *scpd = &scp->domains[i];
struct generic_pm_domain *genpd = &scpd->genpd;
const struct scp_domain_data *data = &scp_domain_data[i];
+ int clk_cnt;

pd_data->domains[i] = genpd;
scpd->scp = scp;
@@ -476,6 +532,18 @@ static struct scp *init_scp(struct platform_device *pdev,
if (ret)
return ERR_PTR(ret);

+ if (data->subsys_clk_prefix) {
+ clk_cnt = init_subsys_clks(pdev,
+ data->subsys_clk_prefix,
+ scpd->subsys_clk);
+ if (clk_cnt < 0) {
+ dev_err(&pdev->dev,
+ "%s: subsys clk unavailable\n",
+ data->name);
+ return ERR_PTR(clk_cnt);
+ }
+ }
+
genpd->name = data->name;
genpd->power_off = scpsys_power_off;
genpd->power_on = scpsys_power_on;
--
1.8.1.1.dirty