Thread (38 messages) 38 messages, 6 authors, 2025-12-10

Re: [PATCH v3 20/21] pmdomain: mediatek: Add bus protect control flow for MT8189

From: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Date: 2025-11-07 10:36:48
Also in: linux-arm-kernel, linux-clk, linux-devicetree, linux-mediatek, linux-pm, lkml

Il 06/11/25 13:42, irving.ch.lin ha scritto:
quoted hunk ↗ jump to hunk
From: Irving-CH Lin <redacted>

In MT8189 mminfra power domain, the bus protect policy separates
into two parts, one is set before subsys clocks enabled, and another
need to enable after subsys clocks enable.

Signed-off-by: Irving-CH Lin <redacted>
---
  drivers/pmdomain/mediatek/mtk-pm-domains.c | 31 ++++++++++++++++++----
  drivers/pmdomain/mediatek/mtk-pm-domains.h |  5 ++++
  2 files changed, 31 insertions(+), 5 deletions(-)
diff --git a/drivers/pmdomain/mediatek/mtk-pm-domains.c b/drivers/pmdomain/mediatek/mtk-pm-domains.c
index 164c6b519af3..222846e52daf 100644
--- a/drivers/pmdomain/mediatek/mtk-pm-domains.c
+++ b/drivers/pmdomain/mediatek/mtk-pm-domains.c
@@ -250,7 +250,7 @@ static int scpsys_bus_protect_set(struct scpsys_domain *pd,
  					MTK_POLL_DELAY_US, MTK_POLL_TIMEOUT);
  }
  
-static int scpsys_bus_protect_enable(struct scpsys_domain *pd)
+static int scpsys_bus_protect_enable(struct scpsys_domain *pd, u8 flags)
  {
  	for (int i = 0; i < SPM_MAX_BUS_PROT_DATA; i++) {
  		const struct scpsys_bus_prot_data *bpd = &pd->data->bp_cfg[i];
@@ -259,6 +259,10 @@ static int scpsys_bus_protect_enable(struct scpsys_domain *pd)
  		if (!bpd->bus_prot_set_clr_mask)
  			break;
  
+		if ((bpd->flags & BUS_PROT_IGNORE_SUBCLK) !=
+		    (flags & BUS_PROT_IGNORE_SUBCLK))
+			continue;
+
  		if (bpd->flags & BUS_PROT_INVERTED)
  			ret = scpsys_bus_protect_clear(pd, bpd);
  		else
@@ -270,7 +274,7 @@ static int scpsys_bus_protect_enable(struct scpsys_domain *pd)
  	return 0;
  }
  
-static int scpsys_bus_protect_disable(struct scpsys_domain *pd)
+static int scpsys_bus_protect_disable(struct scpsys_domain *pd, u8 flags)
  {
  	for (int i = SPM_MAX_BUS_PROT_DATA - 1; i >= 0; i--) {
  		const struct scpsys_bus_prot_data *bpd = &pd->data->bp_cfg[i];
@@ -279,6 +283,10 @@ static int scpsys_bus_protect_disable(struct scpsys_domain *pd)
  		if (!bpd->bus_prot_set_clr_mask)
  			continue;
  
+		if ((bpd->flags & BUS_PROT_IGNORE_SUBCLK) !=
Is that the right name for this flag?

As far as I understand, you have to set bus protection in two steps, right?
So in the first step you're setting bus protection for the MM_INFRA and for
MM_INFRA_2ND - and in the second step you're setting MM_INFRA_IGN and 2_IGN.

So the first step (the prots with BUS_PROT_IGNORE_SUBCLK) unlocks SUBSYS clks
and SRAM ISO access, the second one does the rest.

I think that a better name for this, at this point would be...

if ((bpd->flags & local_flags) & BUS_PROT_SRAM_PROTECTION)
	continue;

What do you think?

Regards,
Angelo
quoted hunk ↗ jump to hunk
+		    (flags & BUS_PROT_IGNORE_SUBCLK))
+			continue;
+
  		if (bpd->flags & BUS_PROT_INVERTED)
  			ret = scpsys_bus_protect_set(pd, bpd);
  		else
@@ -632,6 +640,15 @@ static int scpsys_power_on(struct generic_pm_domain *genpd)
  	if (ret)
  		goto err_pwr_ack;
  
+	/*
+	 * In MT8189 mminfra power domain, the bus protect policy separates
+	 * into two parts, one is set before subsys clocks enabled, and another
+	 * need to enable after subsys clocks enable.
+	 */
+	ret = scpsys_bus_protect_disable(pd, BUS_PROT_IGNORE_SUBCLK);
+	if (ret < 0)
+		goto err_pwr_ack;
+
  	/*
  	 * In few Mediatek platforms(e.g. MT6779), the bus protect policy is
  	 * stricter, which leads to bus protect release must be prior to bus
@@ -648,7 +665,7 @@ static int scpsys_power_on(struct generic_pm_domain *genpd)
  	if (ret < 0)
  		goto err_disable_subsys_clks;
  
-	ret = scpsys_bus_protect_disable(pd);
+	ret = scpsys_bus_protect_disable(pd, 0);
  	if (ret < 0)
  		goto err_disable_sram;
  
@@ -662,7 +679,7 @@ static int scpsys_power_on(struct generic_pm_domain *genpd)
  	return 0;
  
  err_enable_bus_protect:
-	scpsys_bus_protect_enable(pd);
+	scpsys_bus_protect_enable(pd, 0);
  err_disable_sram:
  	scpsys_sram_disable(pd);
  err_disable_subsys_clks:
@@ -683,7 +700,7 @@ static int scpsys_power_off(struct generic_pm_domain *genpd)
  	bool tmp;
  	int ret;
  
-	ret = scpsys_bus_protect_enable(pd);
+	ret = scpsys_bus_protect_enable(pd, 0);
  	if (ret < 0)
  		return ret;
  
@@ -697,6 +714,10 @@ static int scpsys_power_off(struct generic_pm_domain *genpd)
  
  	clk_bulk_disable_unprepare(pd->num_subsys_clks, pd->subsys_clks);
  
+	ret = scpsys_bus_protect_enable(pd, BUS_PROT_IGNORE_SUBCLK);
+	if (ret < 0)
+		return ret;
+
  	if (MTK_SCPD_CAPS(pd, MTK_SCPD_MODEM_PWRSEQ))
  		scpsys_modem_pwrseq_off(pd);
  	else
diff --git a/drivers/pmdomain/mediatek/mtk-pm-domains.h b/drivers/pmdomain/mediatek/mtk-pm-domains.h
index f608e6ec4744..a5dca24cbc2f 100644
--- a/drivers/pmdomain/mediatek/mtk-pm-domains.h
+++ b/drivers/pmdomain/mediatek/mtk-pm-domains.h
@@ -56,6 +56,7 @@ enum scpsys_bus_prot_flags {
  	BUS_PROT_REG_UPDATE = BIT(1),
  	BUS_PROT_IGNORE_CLR_ACK = BIT(2),
  	BUS_PROT_INVERTED = BIT(3),
+	BUS_PROT_IGNORE_SUBCLK = BIT(4),
  };
  
  enum scpsys_bus_prot_block {
@@ -95,6 +96,10 @@ enum scpsys_bus_prot_block {
  		_BUS_PROT(_hwip, _mask, _set, _clr, _mask, _sta,	\
  			  BUS_PROT_REG_UPDATE)
  
+#define BUS_PROT_WR_IGN_SUBCLK(_hwip, _mask, _set, _clr, _sta)		\
+		_BUS_PROT(_hwip, _mask, _set, _clr, _mask, _sta,	\
+			  BUS_PROT_IGNORE_CLR_ACK | BUS_PROT_IGNORE_SUBCLK)
+
  #define BUS_PROT_INFRA_UPDATE_TOPAXI(_mask)			\
  		BUS_PROT_UPDATE(INFRA, _mask,			\
  				INFRA_TOPAXI_PROTECTEN,		\
  
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help