[PATCH v5 6/9] soc: mediatek: extend bus protection API

From: Weiyi Lu
Date: Wed Oct 18 2017 - 22:50:55 EST


MT2712 add "set/clear" bus control register to each control register set
instead of providing only one "enable" control register, we could avoid
the read-modify-write racing by using extend API with such new design.
By improving the mtk-infracfg bus protection implementation to
support set/clear bus protection control method by IC configuration.

Signed-off-by: Weiyi Lu <weiyi.lu@xxxxxxxxxxxx>
---
drivers/soc/mediatek/mtk-infracfg.c | 24 ++++++++++++++++++++----
drivers/soc/mediatek/mtk-scpsys.c | 28 ++++++++++++++++++++--------
include/linux/soc/mediatek/infracfg.h | 7 ++++---
3 files changed, 44 insertions(+), 15 deletions(-)

diff --git a/drivers/soc/mediatek/mtk-infracfg.c b/drivers/soc/mediatek/mtk-infracfg.c
index dba3055..344ffba 100644
--- a/drivers/soc/mediatek/mtk-infracfg.c
+++ b/drivers/soc/mediatek/mtk-infracfg.c
@@ -19,23 +19,32 @@

#define INFRA_TOPAXI_PROTECTEN 0x0220
#define INFRA_TOPAXI_PROTECTSTA1 0x0228
+#define INFRA_TOPAXI_PROTECTEN_SET 0x0260
+#define INFRA_TOPAXI_PROTECTEN_CLR 0x0264

/**
* mtk_infracfg_set_bus_protection - enable bus protection
* @regmap: The infracfg regmap
* @mask: The mask containing the protection bits to be enabled.
+ * @use_reg_set: The boolean flag determines to set the protection bits
+ * by set register or enable register
*
* This function enables the bus protection bits for disabled power
* domains so that the system does not hang when some unit accesses the
* bus while in power down.
*/
-int mtk_infracfg_set_bus_protection(struct regmap *infracfg, u32 mask)
+int mtk_infracfg_set_bus_protection(struct regmap *infracfg, u32 mask,
+ bool use_reg_set)
{
unsigned long expired;
u32 val;
int ret;

- regmap_update_bits(infracfg, INFRA_TOPAXI_PROTECTEN, mask, mask);
+ if (use_reg_set)
+ regmap_write(infracfg, INFRA_TOPAXI_PROTECTEN_SET, mask);
+ else
+ regmap_update_bits(infracfg, INFRA_TOPAXI_PROTECTEN, mask,
+ mask);

expired = jiffies + HZ;

@@ -59,16 +68,23 @@ int mtk_infracfg_set_bus_protection(struct regmap *infracfg, u32 mask)
* mtk_infracfg_clear_bus_protection - disable bus protection
* @regmap: The infracfg regmap
* @mask: The mask containing the protection bits to be disabled.
+ * @use_reg_clr: The boolean flag determines to clear the protection bits
+ * by clear register or enable register
*
* This function disables the bus protection bits previously enabled with
* mtk_infracfg_set_bus_protection.
*/
-int mtk_infracfg_clear_bus_protection(struct regmap *infracfg, u32 mask)
+
+int mtk_infracfg_clear_bus_protection(struct regmap *infracfg, u32 mask,
+ bool use_reg_clr)
{
unsigned long expired;
int ret;

- regmap_update_bits(infracfg, INFRA_TOPAXI_PROTECTEN, mask, 0);
+ if (use_reg_clr)
+ regmap_write(infracfg, INFRA_TOPAXI_PROTECTEN_CLR, mask);
+ else
+ regmap_update_bits(infracfg, INFRA_TOPAXI_PROTECTEN, mask, 0);

expired = jiffies + HZ;

diff --git a/drivers/soc/mediatek/mtk-scpsys.c b/drivers/soc/mediatek/mtk-scpsys.c
index e1ce8b1..ebee3e9 100644
--- a/drivers/soc/mediatek/mtk-scpsys.c
+++ b/drivers/soc/mediatek/mtk-scpsys.c
@@ -134,6 +134,7 @@ struct scp {
void __iomem *base;
struct regmap *infracfg;
struct scp_ctrl_reg ctrl_reg;
+ bool bus_prot_use_set_clr_reg;
};

struct scp_subdomain {
@@ -147,6 +148,7 @@ struct scp_soc_data {
const struct scp_subdomain *subdomains;
int num_subdomains;
const struct scp_ctrl_reg regs;
+ bool bus_prot_use_set_clr_reg;
};

static int scpsys_domain_is_on(struct scp_domain *scpd)
@@ -254,7 +256,8 @@ static int scpsys_power_on(struct generic_pm_domain *genpd)

if (scpd->data->bus_prot_mask) {
ret = mtk_infracfg_clear_bus_protection(scp->infracfg,
- scpd->data->bus_prot_mask);
+ scpd->data->bus_prot_mask,
+ scp->bus_prot_use_set_clr_reg);
if (ret)
goto err_pwr_ack;
}
@@ -289,7 +292,8 @@ static int scpsys_power_off(struct generic_pm_domain *genpd)

if (scpd->data->bus_prot_mask) {
ret = mtk_infracfg_set_bus_protection(scp->infracfg,
- scpd->data->bus_prot_mask);
+ scpd->data->bus_prot_mask,
+ scp->bus_prot_use_set_clr_reg);
if (ret)
goto out;
}
@@ -382,7 +386,8 @@ static void init_clks(struct platform_device *pdev, struct clk **clk)

static struct scp *init_scp(struct platform_device *pdev,
const struct scp_domain_data *scp_domain_data, int num,
- const struct scp_ctrl_reg *scp_ctrl_reg)
+ const struct scp_ctrl_reg *scp_ctrl_reg,
+ bool bus_prot_use_set_clr_reg)
{
struct genpd_onecell_data *pd_data;
struct resource *res;
@@ -397,6 +402,8 @@ static struct scp *init_scp(struct platform_device *pdev,
scp->ctrl_reg.pwr_sta_offs = scp_ctrl_reg->pwr_sta_offs;
scp->ctrl_reg.pwr_sta2nd_offs = scp_ctrl_reg->pwr_sta2nd_offs;

+ scp->bus_prot_use_set_clr_reg = bus_prot_use_set_clr_reg;
+
scp->dev = &pdev->dev;

res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
@@ -816,7 +823,8 @@ static void mtk_register_power_domains(struct platform_device *pdev,
.regs = {
.pwr_sta_offs = SPM_PWR_STATUS,
.pwr_sta2nd_offs = SPM_PWR_STATUS_2ND
- }
+ },
+ .bus_prot_use_set_clr_reg = false,
};

static const struct scp_soc_data mt6797_data = {
@@ -827,7 +835,8 @@ static void mtk_register_power_domains(struct platform_device *pdev,
.regs = {
.pwr_sta_offs = SPM_PWR_STATUS_MT6797,
.pwr_sta2nd_offs = SPM_PWR_STATUS_2ND_MT6797
- }
+ },
+ .bus_prot_use_set_clr_reg = false,
};

static const struct scp_soc_data mt7622_data = {
@@ -836,7 +845,8 @@ static void mtk_register_power_domains(struct platform_device *pdev,
.regs = {
.pwr_sta_offs = SPM_PWR_STATUS,
.pwr_sta2nd_offs = SPM_PWR_STATUS_2ND
- }
+ },
+ .bus_prot_use_set_clr_reg = false,
};

static const struct scp_soc_data mt8173_data = {
@@ -847,7 +857,8 @@ static void mtk_register_power_domains(struct platform_device *pdev,
.regs = {
.pwr_sta_offs = SPM_PWR_STATUS,
.pwr_sta2nd_offs = SPM_PWR_STATUS_2ND
- }
+ },
+ .bus_prot_use_set_clr_reg = false,
};

/*
@@ -884,7 +895,8 @@ static int scpsys_probe(struct platform_device *pdev)
match = of_match_device(of_scpsys_match_tbl, &pdev->dev);
soc = (const struct scp_soc_data *)match->data;

- scp = init_scp(pdev, soc->domains, soc->num_domains, &soc->regs);
+ scp = init_scp(pdev, soc->domains, soc->num_domains, &soc->regs,
+ soc->bus_prot_use_set_clr_reg);
if (IS_ERR(scp))
return PTR_ERR(scp);

diff --git a/include/linux/soc/mediatek/infracfg.h b/include/linux/soc/mediatek/infracfg.h
index a0182ec..7df0fc8 100644
--- a/include/linux/soc/mediatek/infracfg.h
+++ b/include/linux/soc/mediatek/infracfg.h
@@ -27,7 +27,8 @@
#define MT7622_TOP_AXI_PROT_EN_WB (BIT(2) | BIT(6) | \
BIT(7) | BIT(8))

-int mtk_infracfg_set_bus_protection(struct regmap *infracfg, u32 mask);
-int mtk_infracfg_clear_bus_protection(struct regmap *infracfg, u32 mask);
-
+int mtk_infracfg_set_bus_protection(struct regmap *infracfg, u32 mask,
+ bool use_reg_set);
+int mtk_infracfg_clear_bus_protection(struct regmap *infracfg, u32 mask,
+ bool use_reg_clr);
#endif /* __SOC_MEDIATEK_INFRACFG_H */
--
1.9.1