[PATCH 0/3] bus: rifsc: add stm32mp21 support and config dump debug entry

[PATCH 0/3] bus: rifsc: add stm32mp21 support and config dump debug entry

[Gatien Chevallier]

The STM32MP21x platforms have a slightly different RIFSC. Add support
for these platforms.

Also, the RIF is a complex firewall framework which can be tricky
to debug. To facilitate the latter, add a debugfs entry that can
be used to display the whole RIFSC firewall configuration at runtime.

Signed-off-by: Gatien Chevallier <gatien.chevallier@foss.st.com>
---
Gatien Chevallier (3):
      dt-bindings: bus: add stm32mp21 RIFSC compatible
      arm64: dts: st: set RIFSC as an access controller on stm32mp21x platforms
      bus: rifsc: add debugfs entry to dump the firewall configuration

 .../bindings/bus/st,stm32mp25-rifsc.yaml           |   8 +-
 arch/arm64/boot/dts/st/stm32mp211.dtsi             |   4 +-
 drivers/bus/stm32_rifsc.c                          | 600 ++++++++++++++++++++-
 3 files changed, 605 insertions(+), 7 deletions(-)
---
base-commit: 6146a0f1dfae5d37442a9ddcba012add260bceb0
change-id: 20251104-rifsc_debugfs-5053ea033ce3

Best regards,
-- 
Gatien Chevallier <gatien.chevallier@foss.st.com>

[PATCH 1/3] dt-bindings: bus: add stm32mp21 RIFSC compatible

[Gatien Chevallier]

The STM32MP21x platforms have a slightly different RIFSC. While its
core functionalities are similar, the wiring is not the same. Hence,
declare a new compatible.

Signed-off-by: Gatien Chevallier <gatien.chevallier@foss.st.com>
---
 Documentation/devicetree/bindings/bus/st,stm32mp25-rifsc.yaml | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/bus/st,stm32mp25-rifsc.yaml b/Documentation/devicetree/bindings/bus/st,stm32mp25-rifsc.yaml
index 20acd1a6b173..3952c99cac6b 100644
--- a/Documentation/devicetree/bindings/bus/st,stm32mp25-rifsc.yaml
+++ b/Documentation/devicetree/bindings/bus/st,stm32mp25-rifsc.yaml
@@ -33,14 +33,18 @@ select:
   properties:
     compatible:
       contains:
-        const: st,stm32mp25-rifsc
+        enum:
+          - st,stm32mp21-rifsc
+          - st,stm32mp25-rifsc
   required:
     - compatible
 
 properties:
   compatible:
     items:
-      - const: st,stm32mp25-rifsc
+      - enum:
+          - st,stm32mp21-rifsc
+          - st,stm32mp25-rifsc
       - const: simple-bus
 
   reg:

-- 
2.43.0

[PATCH 2/3] arm64: dts: st: set RIFSC as an access controller on stm32mp21x platforms

[Gatien Chevallier]

Similarly to stm32mp23x/25x platforms, the RIFSC is a firewall
controller. Declare it as an access controller, keep the "simple-bus"
compatible in case CONFIG_STM32_FIREWALL is not set and update the
child nodes.

Signed-off-by: Gatien Chevallier <gatien.chevallier@foss.st.com>
---
 arch/arm64/boot/dts/st/stm32mp211.dtsi | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/st/stm32mp211.dtsi b/arch/arm64/boot/dts/st/stm32mp211.dtsi
index bf888d60cd4f..cd078a16065e 100644
--- a/arch/arm64/boot/dts/st/stm32mp211.dtsi
+++ b/arch/arm64/boot/dts/st/stm32mp211.dtsi
@@ -94,18 +94,20 @@ soc@0 {
 		#size-cells = <2>;
 
 		rifsc: bus@42080000 {
-			compatible = "simple-bus";
+			compatible = "st,stm32mp21-rifsc", "simple-bus";
 			reg = <0x42080000 0x0 0x1000>;
 			ranges;
 			dma-ranges;
 			#address-cells = <1>;
 			#size-cells = <2>;
+			#access-controller-cells = <1>;
 
 			usart2: serial@400e0000 {
 				compatible = "st,stm32h7-uart";
 				reg = <0x400e0000 0x0 0x400>;
 				interrupts = <GIC_SPI 102 IRQ_TYPE_LEVEL_HIGH>;
 				clocks = <&ck_flexgen_08>;
+				access-controllers = <&rifsc 32>;
 				status = "disabled";
 			};
 		};

-- 
2.43.0

[PATCH 3/3] bus: rifsc: add debugfs entry to dump the firewall configuration

[Gatien Chevallier]

RIFSC configuration can be difficult to debug. Add a debugfs entry
that dumps the configuration of the RISUPs, the RISALs and the RIMUs.
This will allow to display the whole RIFSC firewall configuration at
runtime.

While there, fix a bug on the computation of firewall entries in the
probe function.

Signed-off-by: Gatien Chevallier <gatien.chevallier@foss.st.com>
---
 drivers/bus/stm32_rifsc.c | 600 +++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 596 insertions(+), 4 deletions(-)

diff --git a/drivers/bus/stm32_rifsc.c b/drivers/bus/stm32_rifsc.c
index 4cf1b60014b7..d8cf081232a3 100644
--- a/drivers/bus/stm32_rifsc.c
+++ b/drivers/bus/stm32_rifsc.c
@@ -5,6 +5,7 @@
 
 #include <linux/bitfield.h>
 #include <linux/bits.h>
+#include <linux/debugfs.h>
 #include <linux/device.h>
 #include <linux/err.h>
 #include <linux/init.h>
@@ -25,6 +26,8 @@
 #define RIFSC_RISC_PRIVCFGR0		0x30
 #define RIFSC_RISC_PER0_CIDCFGR		0x100
 #define RIFSC_RISC_PER0_SEMCR		0x104
+#define RIFSC_RISC_REG0_ACFGR		0x900
+#define RIFSC_RISC_REG3_AADDR		0x924
 #define RIFSC_RISC_HWCFGR2		0xFEC
 
 /*
@@ -70,6 +73,568 @@
 #define RIF_CID0			0x0
 #define RIF_CID1			0x1
 
+#if defined(CONFIG_DEBUG_FS)
+#define RIFSC_RISUP_ENTRIES		128
+#define RIFSC_RIMU_ENTRIES		16
+#define RIFSC_RISAL_SUBREGIONS		2
+#define RIFSC_RISAL_GRANULARITY		8
+
+#define RIFSC_RIMC_ATTR0		0xC10
+
+#define RIFSC_RIMC_CIDSEL		BIT(2)
+#define RIFSC_RIMC_MCID_MASK		GENMASK(6, 4)
+#define RIFSC_RIMC_MSEC			BIT(8)
+#define RIFSC_RIMC_MPRIV		BIT(9)
+
+#define RIFSC_RISC_SRCID_MASK		GENMASK(6, 4)
+#define RIFSC_RISC_SRPRIV		BIT(9)
+#define RIFSC_RISC_SRSEC		BIT(8)
+#define RIFSC_RISC_SRRLOCK		BIT(1)
+#define RIFSC_RISC_SREN			BIT(0)
+#define RIFSC_RISC_SRLENGTH_MASK	GENMASK(27, 16)
+#define RIFSC_RISC_SRSTART_MASK		GENMASK(10, 0)
+
+static const char *stm32mp21_rifsc_rimu_names[RIFSC_RIMU_ENTRIES] = {
+	"ETR",
+	"SDMMC1",
+	"SDMMC2",
+	"SDMMC3",
+	"OTG_HS",
+	"USBH",
+	"ETH1",
+	"ETH2",
+	"RESERVED",
+	"RESERVED",
+	"DCMIPP",
+	"LTDC_L1/L2",
+	"LTDC_L3",
+	"RESERVED",
+	"RESERVED",
+	"RESERVED",
+};
+
+static const char *stm32mp25_rifsc_rimu_names[RIFSC_RIMU_ENTRIES] = {
+	"ETR",
+	"SDMMC1",
+	"SDMMC2",
+	"SDMMC3",
+	"USB3DR",
+	"USBH",
+	"ETH1",
+	"ETH2",
+	"PCIE",
+	"GPU",
+	"DMCIPP",
+	"LTDC_L0/L1",
+	"LTDC_L2",
+	"LTDC_ROT",
+	"VDEC",
+	"VENC"
+};
+
+static const char *stm32mp21_rifsc_risup_names[RIFSC_RISUP_ENTRIES] = {
+	"TIM1",
+	"TIM2",
+	"TIM3",
+	"TIM4",
+	"TIM5",
+	"TIM6",
+	"TIM7",
+	"TIM8",
+	"TIM10",
+	"TIM11",
+	"TIM12",
+	"TIM13",
+	"TIM14",
+	"TIM15",
+	"TIM16",
+	"TIM17",
+	"RESERVED",
+	"LPTIM1",
+	"LPTIM2",
+	"LPTIM3",
+	"LPTIM4",
+	"LPTIM5",
+	"SPI1",
+	"SPI2",
+	"SPI3",
+	"SPI4",
+	"SPI5",
+	"SPI6",
+	"RESERVED",
+	"RESERVED",
+	"SPDIFRX",
+	"USART1",
+	"USART2",
+	"USART3",
+	"UART4",
+	"UART5",
+	"USART6",
+	"UART7",
+	"RESERVED",
+	"RESERVED",
+	"LPUART1",
+	"I2C1",
+	"I2C2",
+	"I2C3",
+	"RESERVED",
+	"RESERVED",
+	"RESERVED",
+	"RESERVED",
+	"RESERVED",
+	"SAI1",
+	"SAI2",
+	"SAI3",
+	"SAI4",
+	"RESERVED",
+	"MDF1",
+	"RESERVED",
+	"FDCAN",
+	"HDP",
+	"ADC1",
+	"ADC2",
+	"ETH1",
+	"ETH2",
+	"RESERVED",
+	"USBH",
+	"RESERVED",
+	"RESERVED",
+	"OTG_HS",
+	"DDRPERFM",
+	"RESERVED",
+	"RESERVED",
+	"RESERVED",
+	"RESERVED",
+	"RESERVED",
+	"STGEN",
+	"OCTOSPI1",
+	"RESERVED",
+	"SDMMC1",
+	"SDMMC2",
+	"SDMMC3",
+	"RESERVED",
+	"LTDC_CMN",
+	"RESERVED",
+	"RESERVED",
+	"RESERVED",
+	"RESERVED",
+	"RESERVED",
+	"CSI",
+	"DCMIPP",
+	"DCMI_PSSI",
+	"RESERVED",
+	"RESERVED",
+	"RESERVED",
+	"RNG1",
+	"RNG2",
+	"PKA",
+	"SAES",
+	"HASH1",
+	"HASH2",
+	"CRYP1",
+	"CRYP2",
+	"IWDG1",
+	"IWDG2",
+	"IWDG3",
+	"IWDG4",
+	"WWDG1",
+	"RESERVED",
+	"VREFBUF",
+	"DTS",
+	"RAMCFG",
+	"CRC",
+	"SERC",
+	"RESERVED",
+	"RESERVED",
+	"RESERVED",
+	"I3C1",
+	"I3C2",
+	"I3C3",
+	"RESERVED",
+	"ICACHE_DCACHE",
+	"LTDC_L1L2",
+	"LTDC_L3",
+	"RESERVED",
+	"RESERVED",
+	"RESERVED",
+	"RESERVED",
+	"OTFDEC1",
+	"RESERVED",
+	"IAC",
+};
+
+static const char *stm32mp25_rifsc_risup_names[RIFSC_RISUP_ENTRIES] = {
+	"TIM1",
+	"TIM2",
+	"TIM3",
+	"TIM4",
+	"TIM5",
+	"TIM6",
+	"TIM7",
+	"TIM8",
+	"TIM10",
+	"TIM11",
+	"TIM12",
+	"TIM13",
+	"TIM14",
+	"TIM15",
+	"TIM16",
+	"TIM17",
+	"TIM20",
+	"LPTIM1",
+	"LPTIM2",
+	"LPTIM3",
+	"LPTIM4",
+	"LPTIM5",
+	"SPI1",
+	"SPI2",
+	"SPI3",
+	"SPI4",
+	"SPI5",
+	"SPI6",
+	"SPI7",
+	"SPI8",
+	"SPDIFRX",
+	"USART1",
+	"USART2",
+	"USART3",
+	"UART4",
+	"UART5",
+	"USART6",
+	"UART7",
+	"UART8",
+	"UART9",
+	"LPUART1",
+	"I2C1",
+	"I2C2",
+	"I2C3",
+	"I2C4",
+	"I2C5",
+	"I2C6",
+	"I2C7",
+	"I2C8",
+	"SAI1",
+	"SAI2",
+	"SAI3",
+	"SAI4",
+	"RESERVED",
+	"MDF1",
+	"ADF1",
+	"FDCAN",
+	"HDP",
+	"ADC12",
+	"ADC3",
+	"ETH1",
+	"ETH2",
+	"RESERVED",
+	"USBH",
+	"RESERVED",
+	"RESERVED",
+	"USB3DR",
+	"COMBOPHY",
+	"PCIE",
+	"UCPD1",
+	"ETHSW_DEIP",
+	"ETHSW_ACM_CF",
+	"ETHSW_ACM_MSGBU",
+	"STGEN",
+	"OCTOSPI1",
+	"OCTOSPI2",
+	"SDMMC1",
+	"SDMMC2",
+	"SDMMC3",
+	"GPU",
+	"LTDC_CMN",
+	"DSI_CMN",
+	"RESERVED",
+	"RESERVED",
+	"LVDS",
+	"RESERVED",
+	"CSI",
+	"DCMIPP",
+	"DCMI_PSSI",
+	"VDEC",
+	"VENC",
+	"RESERVED",
+	"RNG",
+	"PKA",
+	"SAES",
+	"HASH",
+	"CRYP1",
+	"CRYP2",
+	"IWDG1",
+	"IWDG2",
+	"IWDG3",
+	"IWDG4",
+	"IWDG5",
+	"WWDG1",
+	"WWDG2",
+	"RESERVED",
+	"VREFBUF",
+	"DTS",
+	"RAMCFG",
+	"CRC",
+	"SERC",
+	"OCTOSPIM",
+	"GICV2M",
+	"RESERVED",
+	"I3C1",
+	"I3C2",
+	"I3C3",
+	"I3C4",
+	"ICACHE_DCACHE",
+	"LTDC_L0L1",
+	"LTDC_L2",
+	"LTDC_ROT",
+	"DSI_TRIG",
+	"DSI_RDFIFO",
+	"RESERVED",
+	"OTFDEC1",
+	"OTFDEC2",
+	"IAC",
+};
+struct rifsc_risup_debug_data {
+	char dev_name[15];
+	u8 dev_cid;
+	u8 dev_sem_cids;
+	u8 dev_id;
+	bool dev_cid_filt_en;
+	bool dev_sem_en;
+	bool dev_priv;
+	bool dev_sec;
+};
+
+struct rifsc_rimu_debug_data {
+	char m_name[11];
+	u8 m_cid;
+	bool cidsel;
+	bool m_sec;
+	bool m_priv;
+};
+
+struct rifsc_subreg_debug_data {
+	bool sr_sec;
+	bool sr_priv;
+	u8 sr_cid;
+	bool sr_rlock;
+	bool sr_enable;
+	u16 sr_start;
+	u16 sr_length;
+};
+
+struct stm32_rifsc_resources_names {
+	const char **device_names;
+	const char **initiator_names;
+};
+struct rifsc_dbg_private {
+	const struct stm32_rifsc_resources_names *res_names;
+	void __iomem *mmio;
+	unsigned int nb_risup;
+	unsigned int nb_rimu;
+	unsigned int nb_risal;
+};
+
+static const struct stm32_rifsc_resources_names rifsc_mp21_res_names = {
+	.device_names = stm32mp21_rifsc_risup_names,
+	.initiator_names = stm32mp21_rifsc_rimu_names,
+};
+
+static const struct stm32_rifsc_resources_names rifsc_mp25_res_names = {
+	.device_names = stm32mp25_rifsc_risup_names,
+	.initiator_names = stm32mp25_rifsc_rimu_names,
+};
+
+static void stm32_rifsc_fill_rimu_dbg_entry(struct rifsc_dbg_private *rifsc,
+					    struct rifsc_rimu_debug_data *dbg_entry, int i)
+{
+	const struct stm32_rifsc_resources_names *dbg_names = rifsc->res_names;
+	u32 rimc_attr = readl_relaxed(rifsc->mmio + RIFSC_RIMC_ATTR0 + 0x4 * i);
+
+	snprintf(dbg_entry->m_name, sizeof(dbg_entry->m_name), "%s", dbg_names->initiator_names[i]);
+	dbg_entry->m_cid = FIELD_GET(RIFSC_RIMC_MCID_MASK, rimc_attr);
+	dbg_entry->cidsel = rimc_attr & RIFSC_RIMC_CIDSEL;
+	dbg_entry->m_sec = rimc_attr & RIFSC_RIMC_MSEC;
+	dbg_entry->m_priv = rimc_attr & RIFSC_RIMC_MPRIV;
+}
+
+static void stm32_rifsc_fill_dev_dbg_entry(struct rifsc_dbg_private *rifsc,
+					   struct rifsc_risup_debug_data *dbg_entry, int i)
+{
+	const struct stm32_rifsc_resources_names *dbg_names = rifsc->res_names;
+	u32 cid_cfgr, sec_cfgr, priv_cfgr;
+	u8 reg_id = i / IDS_PER_RISC_SEC_PRIV_REGS;
+	u8 reg_offset = i % IDS_PER_RISC_SEC_PRIV_REGS;
+
+	cid_cfgr = readl_relaxed(rifsc->mmio + RIFSC_RISC_PER0_CIDCFGR + 0x8 * i);
+	sec_cfgr = readl_relaxed(rifsc->mmio + RIFSC_RISC_SECCFGR0 + 0x4 * reg_id);
+	priv_cfgr = readl_relaxed(rifsc->mmio + RIFSC_RISC_PRIVCFGR0 + 0x4 * reg_id);
+
+	snprintf(dbg_entry->dev_name, sizeof(dbg_entry->dev_name), "%s",
+		 dbg_names->device_names[i]);
+	dbg_entry->dev_id = i;
+	dbg_entry->dev_cid_filt_en = cid_cfgr & CIDCFGR_CFEN;
+	dbg_entry->dev_sem_en = cid_cfgr & CIDCFGR_SEMEN;
+	dbg_entry->dev_cid = FIELD_GET(RIFSC_RISC_SCID_MASK, cid_cfgr);
+	dbg_entry->dev_sem_cids = FIELD_GET(RIFSC_RISC_SEMWL_MASK, cid_cfgr);
+	dbg_entry->dev_sec = sec_cfgr & BIT(reg_offset) ?  true : false;
+	dbg_entry->dev_priv = priv_cfgr & BIT(reg_offset) ?  true : false;
+}
+
+
+static void stm32_rifsc_fill_subreg_dbg_entry(struct rifsc_dbg_private *rifsc,
+					      struct rifsc_subreg_debug_data *dbg_entry, int i,
+					      int j)
+{
+	u32 risc_xcfgr = readl_relaxed(rifsc->mmio + RIFSC_RISC_REG0_ACFGR + 0x10 * i + 0x8 * j);
+	u32 risc_xaddr;
+
+	dbg_entry->sr_sec = risc_xcfgr & RIFSC_RISC_SRSEC;
+	dbg_entry->sr_priv = risc_xcfgr & RIFSC_RISC_SRPRIV;
+	dbg_entry->sr_cid = FIELD_GET(RIFSC_RISC_SRCID_MASK, risc_xcfgr);
+	dbg_entry->sr_rlock = risc_xcfgr & RIFSC_RISC_SRRLOCK;
+	dbg_entry->sr_enable = risc_xcfgr & RIFSC_RISC_SREN;
+	if (i == 2) {
+		risc_xaddr = readl_relaxed(rifsc->mmio + RIFSC_RISC_REG3_AADDR + 0x8 * j);
+		dbg_entry->sr_length = FIELD_GET(RIFSC_RISC_SRLENGTH_MASK, risc_xaddr);
+		dbg_entry->sr_start = FIELD_GET(RIFSC_RISC_SRSTART_MASK, risc_xaddr);
+	} else {
+		dbg_entry->sr_start = 0;
+		dbg_entry->sr_length = U16_MAX;
+	}
+}
+
+static int stm32_rifsc_conf_dump_show(struct seq_file *s, void *data)
+{
+	struct rifsc_dbg_private *rifsc = (struct rifsc_dbg_private *)s->private;
+	int i, j;
+
+	seq_puts(s, "\n=============================================\n");
+	seq_puts(s, "                 RIFSC dump\n");
+	seq_puts(s, "=============================================\n\n");
+
+	seq_puts(s, "\n=============================================\n");
+	seq_puts(s, "                 RISUP dump\n");
+	seq_puts(s, "=============================================\n");
+
+	seq_printf(s, "\n| %-15s |", "Peripheral name");
+	seq_puts(s, "| Firewall ID |");
+	seq_puts(s, "| N/SECURE |");
+	seq_puts(s, "| N/PRIVILEGED |");
+	seq_puts(s, "| CID filtering |");
+	seq_puts(s, "| Semaphore mode |");
+	seq_puts(s, "| SCID |");
+	seq_printf(s, "| %7s |\n", "SEMWL");
+
+	for (i = 0; i < RIFSC_RISUP_ENTRIES && i < rifsc->nb_risup; i++) {
+		struct rifsc_risup_debug_data d_dbg_entry;
+
+		stm32_rifsc_fill_dev_dbg_entry(rifsc, &d_dbg_entry, i);
+
+		seq_printf(s, "| %-15s |", d_dbg_entry.dev_name);
+		seq_printf(s, "| %-11d |", d_dbg_entry.dev_id);
+		seq_printf(s, "| %-8s |", d_dbg_entry.dev_sec ? "SEC" : "NSEC");
+		seq_printf(s, "| %-12s |", d_dbg_entry.dev_priv ? "PRIV" : "NPRIV");
+		seq_printf(s, "| %-13s |",
+			   d_dbg_entry.dev_cid_filt_en ? "enabled" : "disabled");
+		seq_printf(s, "| %-14s |",
+			   d_dbg_entry.dev_sem_en ? "enabled" : "disabled");
+		seq_printf(s, "| %-4d |", d_dbg_entry.dev_cid);
+		seq_printf(s, "| %#-7x |\n", d_dbg_entry.dev_sem_cids);
+	}
+
+	seq_puts(s, "\n=============================================\n");
+	seq_puts(s, "                  RIMU dump\n");
+	seq_puts(s, "=============================================\n");
+
+	seq_puts(s, "| RIMU's name |");
+	seq_puts(s, "| CIDSEL |");
+	seq_puts(s, "| MCID |");
+	seq_puts(s, "| N/SECURE |");
+	seq_puts(s, "| N/PRIVILEGED |\n");
+
+	for (i = 0; i < RIFSC_RIMU_ENTRIES && rifsc->nb_rimu; i++) {
+		struct rifsc_rimu_debug_data m_dbg_entry;
+
+		stm32_rifsc_fill_rimu_dbg_entry(rifsc, &m_dbg_entry, i);
+
+		seq_printf(s, "| %-11s |", m_dbg_entry.m_name);
+		seq_printf(s, "| %-6s |", m_dbg_entry.cidsel ? "CIDSEL" : "");
+		seq_printf(s, "| %-4d |", m_dbg_entry.m_cid);
+		seq_printf(s, "| %-8s |", m_dbg_entry.m_sec ? "SEC" : "NSEC");
+		seq_printf(s, "| %-12s |\n", m_dbg_entry.m_priv ? "PRIV" : "NPRIV");
+	}
+
+	if (rifsc->nb_risal > 0) {
+		seq_puts(s, "\n=============================================\n");
+		seq_puts(s, "                  RISAL dump\n");
+		seq_puts(s, "=============================================\n");
+
+		seq_puts(s, "| Memory  |");
+		seq_puts(s, "| Subreg. |");
+		seq_puts(s, "| N/SECURE |");
+		seq_puts(s, "| N/PRIVILEGED |");
+		seq_puts(s, "| Subreg. CID |");
+		seq_puts(s, "| Resource lock |");
+		seq_puts(s, "| Subreg. enable |");
+		seq_puts(s, "| Subreg. start |");
+		seq_puts(s, "|  Subreg. end  |\n");
+
+		for (i = 0; i < rifsc->nb_risal; i++) {
+			for (j = 0; j < RIFSC_RISAL_SUBREGIONS; j++) {
+				struct rifsc_subreg_debug_data sr_dbg_entry;
+
+				stm32_rifsc_fill_subreg_dbg_entry(rifsc, &sr_dbg_entry, i, j);
+
+				seq_printf(s, "| LPSRAM%1d |", i + 1);
+				seq_printf(s, "|    %1s    |", (j == 0) ? "A" : "B");
+				seq_printf(s, "| %-8s |", sr_dbg_entry.sr_sec ? "SEC" : "NSEC");
+				seq_printf(s, "| %-12s |", sr_dbg_entry.sr_priv ? "PRIV" : "NPRIV");
+				seq_printf(s, "| 0x%-9x |", sr_dbg_entry.sr_cid);
+				seq_printf(s, "| %-13s |",
+					   sr_dbg_entry.sr_rlock ? "locked (1)" : "unlocked (0)");
+				seq_printf(s, "| %-14s |",
+					   sr_dbg_entry.sr_enable ? "enabled" : "disabled");
+
+				seq_printf(s, "| 0x%-11x |", sr_dbg_entry.sr_start);
+				seq_printf(s, "| 0x%-11x |\n", sr_dbg_entry.sr_start +
+					   sr_dbg_entry.sr_length - 1);
+			}
+		}
+	}
+
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(stm32_rifsc_conf_dump);
+
+static int stm32_rifsc_register_debugfs(struct stm32_firewall_controller *rifsc_controller,
+					u32 nb_risup, u32 nb_rimu, u32 nb_risal)
+{
+	struct rifsc_dbg_private *rifsc_priv;
+	struct dentry *root = NULL;
+
+	rifsc_priv = devm_kzalloc(rifsc_controller->dev, sizeof(*rifsc_priv), GFP_KERNEL);
+	if (!rifsc_priv)
+		return -ENOMEM;
+
+	rifsc_priv->mmio = rifsc_controller->mmio;
+	rifsc_priv->nb_risup = nb_risup;
+	rifsc_priv->nb_rimu = nb_rimu;
+	rifsc_priv->nb_risal = nb_risal;
+	rifsc_priv->res_names = of_device_get_match_data(rifsc_controller->dev);
+
+	root = debugfs_lookup("stm32_firewall", NULL);
+	if (!root)
+		root = debugfs_create_dir("stm32_firewall", NULL);
+
+	if (IS_ERR(root))
+		return PTR_ERR(root);
+
+	debugfs_create_file("rifsc", 0444, root, rifsc_priv, &stm32_rifsc_conf_dump_fops);
+
+	return 0;
+}
+#endif /* defined(CONFIG_DEBUG_FS) */
+
 static bool stm32_rifsc_is_semaphore_available(void __iomem *addr)
 {
 	return !(readl(addr) & SEMCR_MUTEX);
@@ -207,9 +772,19 @@ static int stm32_rifsc_probe(struct platform_device *pdev)
 	rifsc_controller->release_access = stm32_rifsc_release_access;
 
 	/* Get number of RIFSC entries*/
-	nb_risup = readl(rifsc_controller->mmio + RIFSC_RISC_HWCFGR2) & HWCFGR2_CONF1_MASK;
-	nb_rimu = readl(rifsc_controller->mmio + RIFSC_RISC_HWCFGR2) & HWCFGR2_CONF2_MASK;
-	nb_risal = readl(rifsc_controller->mmio + RIFSC_RISC_HWCFGR2) & HWCFGR2_CONF3_MASK;
+	nb_risup = FIELD_GET(HWCFGR2_CONF1_MASK,
+			     readl(rifsc_controller->mmio + RIFSC_RISC_HWCFGR2));
+	nb_rimu = FIELD_GET(HWCFGR2_CONF2_MASK,
+			    readl(rifsc_controller->mmio + RIFSC_RISC_HWCFGR2));
+	nb_risal = FIELD_GET(HWCFGR2_CONF3_MASK,
+			     readl(rifsc_controller->mmio + RIFSC_RISC_HWCFGR2));
+	/*
+	 * On STM32MP21, RIFSC_RISC_HWCFGR2 shows an incorrect number of RISAL (NUM_RISAL is 3
+	 * instead of 0). A software workaround is implemented using the st,mem-map property in the
+	 * device tree. This property is absent or left empty if there is no RISAL.
+	 */
+	if (of_device_is_compatible(np, "st,stm32mp21-rifsc"))
+		nb_risal = 0;
 	rifsc_controller->max_entries = nb_risup + nb_rimu + nb_risal;
 
 	platform_set_drvdata(pdev, rifsc_controller);
@@ -228,12 +803,29 @@ static int stm32_rifsc_probe(struct platform_device *pdev)
 		return rc;
 	}
 
+#if defined(CONFIG_DEBUG_FS)
+	rc = stm32_rifsc_register_debugfs(rifsc_controller, nb_risup, nb_rimu, nb_risal);
+	if (rc)
+		return dev_err_probe(rifsc_controller->dev, rc, "Failed creating debugfs entry\n");
+#endif
+
 	/* Populate all allowed nodes */
 	return of_platform_populate(np, NULL, NULL, &pdev->dev);
 }
 
 static const struct of_device_id stm32_rifsc_of_match[] = {
-	{ .compatible = "st,stm32mp25-rifsc" },
+	{
+		.compatible = "st,stm32mp25-rifsc",
+#if defined(CONFIG_DEBUG_FS)
+		.data = &rifsc_mp25_res_names,
+#endif
+	},
+	{
+		.compatible = "st,stm32mp21-rifsc",
+#if defined(CONFIG_DEBUG_FS)
+		.data = &rifsc_mp21_res_names,
+#endif
+	},
 	{}
 };
 MODULE_DEVICE_TABLE(of, stm32_rifsc_of_match);

-- 
2.43.0

Re: [PATCH 1/3] dt-bindings: bus: add stm32mp21 RIFSC compatible

[Conor Dooley]

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On Tue, Nov 04, 2025 at 02:54:10PM +0100, Gatien Chevallier wrote:
> The STM32MP21x platforms have a slightly different RIFSC. While its
> core functionalities are similar, the wiring is not the same. Hence,
> declare a new compatible.
> 
> Signed-off-by: Gatien Chevallier <gatien.chevallier@foss.st.com>

Acked-by: Conor Dooley <conor.dooley@microchip.com>
pw-bot: not-applicable

[-- Attachment #2: signature.asc --]
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Re: [PATCH 3/3] bus: rifsc: add debugfs entry to dump the firewall configuration

[kernel test robot]

Hi Gatien,

kernel test robot noticed the following build warnings:

[auto build test WARNING on 6146a0f1dfae5d37442a9ddcba012add260bceb0]

url:    https://github.com/intel-lab-lkp/linux/commits/Gatien-Chevallier/dt-bindings-bus-add-stm32mp21-RIFSC-compatible/20251104-215726
base:   6146a0f1dfae5d37442a9ddcba012add260bceb0
patch link:    https://lore.kernel.org/r/20251104-rifsc_debugfs-v1-3-7ebdfbf8d33f%40foss.st.com
patch subject: [PATCH 3/3] bus: rifsc: add debugfs entry to dump the firewall configuration
config: csky-randconfig-r062-20251105 (https://download.01.org/0day-ci/archive/20251106/202511060449.FdKTConU-lkp@intel.com/config)
compiler: csky-linux-gcc (GCC) 15.1.0

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202511060449.FdKTConU-lkp@intel.com/

cocci warnings: (new ones prefixed by >>)
>> drivers/bus/stm32_rifsc.c:538:6-33: opportunity for str_enabled_disabled(d_dbg_entry . dev_cid_filt_en)
>> drivers/bus/stm32_rifsc.c:540:6-28: opportunity for str_enabled_disabled(d_dbg_entry . dev_sem_en)
>> drivers/bus/stm32_rifsc.c:596:8-30: opportunity for str_enabled_disabled(sr_dbg_entry . sr_enable)

vim +538 drivers/bus/stm32_rifsc.c

   505	
   506	static int stm32_rifsc_conf_dump_show(struct seq_file *s, void *data)
   507	{
   508		struct rifsc_dbg_private *rifsc = (struct rifsc_dbg_private *)s->private;
   509		int i, j;
   510	
   511		seq_puts(s, "\n=============================================\n");
   512		seq_puts(s, "                 RIFSC dump\n");
   513		seq_puts(s, "=============================================\n\n");
   514	
   515		seq_puts(s, "\n=============================================\n");
   516		seq_puts(s, "                 RISUP dump\n");
   517		seq_puts(s, "=============================================\n");
   518	
   519		seq_printf(s, "\n| %-15s |", "Peripheral name");
   520		seq_puts(s, "| Firewall ID |");
   521		seq_puts(s, "| N/SECURE |");
   522		seq_puts(s, "| N/PRIVILEGED |");
   523		seq_puts(s, "| CID filtering |");
   524		seq_puts(s, "| Semaphore mode |");
   525		seq_puts(s, "| SCID |");
   526		seq_printf(s, "| %7s |\n", "SEMWL");
   527	
   528		for (i = 0; i < RIFSC_RISUP_ENTRIES && i < rifsc->nb_risup; i++) {
   529			struct rifsc_risup_debug_data d_dbg_entry;
   530	
   531			stm32_rifsc_fill_dev_dbg_entry(rifsc, &d_dbg_entry, i);
   532	
   533			seq_printf(s, "| %-15s |", d_dbg_entry.dev_name);
   534			seq_printf(s, "| %-11d |", d_dbg_entry.dev_id);
   535			seq_printf(s, "| %-8s |", d_dbg_entry.dev_sec ? "SEC" : "NSEC");
   536			seq_printf(s, "| %-12s |", d_dbg_entry.dev_priv ? "PRIV" : "NPRIV");
   537			seq_printf(s, "| %-13s |",
 > 538				   d_dbg_entry.dev_cid_filt_en ? "enabled" : "disabled");
   539			seq_printf(s, "| %-14s |",
 > 540				   d_dbg_entry.dev_sem_en ? "enabled" : "disabled");
   541			seq_printf(s, "| %-4d |", d_dbg_entry.dev_cid);
   542			seq_printf(s, "| %#-7x |\n", d_dbg_entry.dev_sem_cids);
   543		}
   544	
   545		seq_puts(s, "\n=============================================\n");
   546		seq_puts(s, "                  RIMU dump\n");
   547		seq_puts(s, "=============================================\n");
   548	
   549		seq_puts(s, "| RIMU's name |");
   550		seq_puts(s, "| CIDSEL |");
   551		seq_puts(s, "| MCID |");
   552		seq_puts(s, "| N/SECURE |");
   553		seq_puts(s, "| N/PRIVILEGED |\n");
   554	
   555		for (i = 0; i < RIFSC_RIMU_ENTRIES && rifsc->nb_rimu; i++) {
   556			struct rifsc_rimu_debug_data m_dbg_entry;
   557	
   558			stm32_rifsc_fill_rimu_dbg_entry(rifsc, &m_dbg_entry, i);
   559	
   560			seq_printf(s, "| %-11s |", m_dbg_entry.m_name);
   561			seq_printf(s, "| %-6s |", m_dbg_entry.cidsel ? "CIDSEL" : "");
   562			seq_printf(s, "| %-4d |", m_dbg_entry.m_cid);
   563			seq_printf(s, "| %-8s |", m_dbg_entry.m_sec ? "SEC" : "NSEC");
   564			seq_printf(s, "| %-12s |\n", m_dbg_entry.m_priv ? "PRIV" : "NPRIV");
   565		}
   566	
   567		if (rifsc->nb_risal > 0) {
   568			seq_puts(s, "\n=============================================\n");
   569			seq_puts(s, "                  RISAL dump\n");
   570			seq_puts(s, "=============================================\n");
   571	
   572			seq_puts(s, "| Memory  |");
   573			seq_puts(s, "| Subreg. |");
   574			seq_puts(s, "| N/SECURE |");
   575			seq_puts(s, "| N/PRIVILEGED |");
   576			seq_puts(s, "| Subreg. CID |");
   577			seq_puts(s, "| Resource lock |");
   578			seq_puts(s, "| Subreg. enable |");
   579			seq_puts(s, "| Subreg. start |");
   580			seq_puts(s, "|  Subreg. end  |\n");
   581	
   582			for (i = 0; i < rifsc->nb_risal; i++) {
   583				for (j = 0; j < RIFSC_RISAL_SUBREGIONS; j++) {
   584					struct rifsc_subreg_debug_data sr_dbg_entry;
   585	
   586					stm32_rifsc_fill_subreg_dbg_entry(rifsc, &sr_dbg_entry, i, j);
   587	
   588					seq_printf(s, "| LPSRAM%1d |", i + 1);
   589					seq_printf(s, "|    %1s    |", (j == 0) ? "A" : "B");
   590					seq_printf(s, "| %-8s |", sr_dbg_entry.sr_sec ? "SEC" : "NSEC");
   591					seq_printf(s, "| %-12s |", sr_dbg_entry.sr_priv ? "PRIV" : "NPRIV");
   592					seq_printf(s, "| 0x%-9x |", sr_dbg_entry.sr_cid);
   593					seq_printf(s, "| %-13s |",
   594						   sr_dbg_entry.sr_rlock ? "locked (1)" : "unlocked (0)");
   595					seq_printf(s, "| %-14s |",
 > 596						   sr_dbg_entry.sr_enable ? "enabled" : "disabled");
   597	
   598					seq_printf(s, "| 0x%-11x |", sr_dbg_entry.sr_start);
   599					seq_printf(s, "| 0x%-11x |\n", sr_dbg_entry.sr_start +
   600						   sr_dbg_entry.sr_length - 1);
   601				}
   602			}
   603		}
   604	
   605		return 0;
   606	}
   607	DEFINE_SHOW_ATTRIBUTE(stm32_rifsc_conf_dump);
   608	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki