drivers: memc: Add support for siwx91x QSPI controller

Silabs siwx91x includes a memory controller for (Quad-)SPI PSRAM. It
allows the application to use the PSRAM as if it was any other RAM.

Signed-off-by: Jérôme Pouiller <jerome.pouiller@silabs.com>

drivers/clock_control/clock_control_silabs_siwx91x.c

@@ -82,6 +82,9 @@ static int siwx91x_clock_on(const struct device *dev, clock_control_subsys_t sys
 		RSI_PS_M4ssPeriPowerUp(M4SS_PWRGATE_ULP_EFUSE_PERI);
 		RSI_CLK_GspiClkConfig(M4CLK, GSPI_INTF_PLL_CLK);
 		break;
+	case SIWX91X_CLK_QSPI:
+		RSI_CLK_Qspi2ClkConfig(M4CLK, QSPI_ULPREFCLK, 0, 0, 0);
+		break;
 	default:
 		return -EINVAL;
 	}

drivers/memc/CMakeLists.txt

@@ -20,6 +20,7 @@ zephyr_library_include_directories_ifdef(CONFIG_MEMC_MSPI_APS6404L ${ZEPHYR_BASE
 zephyr_library_sources_ifdef(CONFIG_MEMC_NXP_S32_QSPI            memc_nxp_s32_qspi.c)
 zephyr_library_sources_ifdef(CONFIG_MEMC_RENESAS_RA_SDRAM        memc_renesas_ra_sdram.c)
 zephyr_library_sources_ifdef(CONFIG_MEMC_SAM_SMC                 memc_sam_smc.c)
+zephyr_library_sources_ifdef(CONFIG_MEMC_SILABS_SIWX91X_QSPI     memc_silabs_siwx91x_qspi.c)
 zephyr_library_sources_ifdef(CONFIG_MEMC_SMARTBOND               memc_smartbond_nor_psram.c)
 zephyr_library_sources_ifdef(CONFIG_MEMC_STM32                   memc_stm32.c)
 zephyr_library_sources_ifdef(CONFIG_MEMC_STM32_NOR_PSRAM         memc_stm32_nor_psram.c)

drivers/memc/Kconfig

@@ -26,6 +26,7 @@ source "drivers/memc/Kconfig.nxp_s32"
 source "drivers/memc/Kconfig.renesas_ra"
 source "drivers/memc/Kconfig.sam"
 source "drivers/memc/Kconfig.sifive"
+source "drivers/memc/Kconfig.siwx91x_qspi"
 source "drivers/memc/Kconfig.smartbond"
 source "drivers/memc/Kconfig.stm32"
 # zephyr-keep-sorted-stop

drivers/memc/Kconfig.siwx91x_qspi

@@ -0,0 +1,18 @@
+# Copyright (c) 2025 Silicon Laboratories Inc.
+# SPDX-License-Identifier: Apache-2.0
+
+config MEMC_SILABS_SIWX91X_QSPI
+	bool "Silabs SiWx91x QSPI memory controller"
+	default y
+	depends on DT_HAS_SILABS_SIWX91X_QSPI_MEMORY_ENABLED
+	select PINCTRL
+	help
+	  Enable Silabs SiWx91x QSPI (Quad Serial Peripheral Interface) memory
+	  controller.
+
+	  If you want to rely on the linker to place symbols in this memory
+	  (using`zephyr_code_relocate() or Z_GENERIC_SECTION()), you have to
+	  ensure this driver in initialized before KERNEL_INIT_PRIORITY_OBJECTS
+	  (=30). In addition, this driver may depends on a clock. Then, you have
+	  to ensure the clock will be started before this driver (see
+	  CLOCK_CONTROL_INIT_PRIORITY)

drivers/memc/memc_silabs_siwx91x_qspi.c

@@ -0,0 +1,122 @@
+/* Copyright (c) 2025 Silicon Laboratories Inc.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#define DT_DRV_COMPAT silabs_siwx91x_qspi_memory
+#include <zephyr/logging/log.h>
+#include <zephyr/drivers/clock_control.h>
+#include <zephyr/drivers/pinctrl.h>
+
+#include <zephyr/sys/util.h>
+#include <zephyr/device.h>
+#include <zephyr/kernel.h>
+
+#include "rsi_qspi_proto.h"
+#include "sl_si91x_psram_handle.h"
+
+LOG_MODULE_REGISTER(siwx91x_memc, CONFIG_MEMC_LOG_LEVEL);
+
+struct siwx91x_memc_config {
+	qspi_reg_t *reg;
+	const struct device *clock_dev;
+	clock_control_subsys_t clock_subsys;
+	const struct pinctrl_dev_config *pincfg;
+};
+
+static int siwx91x_memc_init(const struct device *dev)
+{
+	const struct siwx91x_memc_config *config = dev->config;
+	int ret;
+
+	/* Memory controller is automatically setup by the siwx91x bootloader,
+	 * so we have to uninitialize it before to change the configuration
+	 */
+	ret = sl_si91x_psram_uninit();
+	if (ret) {
+		return -EIO;
+	}
+
+	ret = pinctrl_apply_state(config->pincfg, PINCTRL_STATE_DEFAULT);
+	if (ret) {
+		return -EIO;
+	}
+	if (config->clock_dev) {
+		ret = device_is_ready(config->clock_dev);
+		if (!ret) {
+			return -EINVAL;
+		}
+		ret = clock_control_on(config->clock_dev, config->clock_subsys);
+		if (ret && ret != -EALREADY && ret != -ENOSYS) {
+			return ret;
+		}
+	}
+
+	ret = sl_si91x_psram_init();
+	if (ret) {
+		LOG_ERR("sl_si91x_psram_init() returned %d", ret);
+		return -EIO;
+	}
+
+	return 0;
+}
+
+PINCTRL_DT_INST_DEFINE(0);
+static const struct siwx91x_memc_config siwx91x_memc_config = {
+	.reg = (void *)DT_INST_REG_ADDR(0),
+	.clock_dev = DEVICE_DT_GET_OR_NULL(DT_INST_CLOCKS_CTLR(0)),
+	.clock_subsys = (void *)DT_INST_PHA_OR(0, clocks, clkid, NULL),
+	.pincfg = PINCTRL_DT_INST_DEV_CONFIG_GET(0),
+};
+/* Required to properly initialize ,deviceID */
+static const uint8_t devid[] = DT_INST_PROP(0, device_id);
+
+/* PSRAM_Device is directly referenced by sl_si91x_psram_init() */
+struct sl_psram_info_type_t PSRAM_Device = {
+	.deviceID.MFID          = devid[0],
+	.deviceID.KGD           = devid[1],
+	.deviceID.EID           = { devid[2], devid[3], devid[4], devid[5], devid[6], devid[7] },
+	/* FIXME: Currently, the Chip Select (.cs_no property) and the RAM start
+	 * address are hard coded. The hardware also support Chip Select == 1,
+	 * then RAM start address will be 0xb000000.
+	 */
+	.devDensity             = DT_REG_SIZE(DT_INST_CHILD(0, psram_a000000)),
+	.normalReadMAXFrequency = DT_INST_PROP(0, normal_freq),
+	.fastReadMAXFrequency   = DT_INST_PROP(0, fast_freq),
+	.rwType                 = QUAD_RW,
+	.defaultBurstWrapSize   = 1024,
+	.toggleBurstWrapSize    = 0,
+	.spi_config.spi_config_2.auto_mode         = 1,
+	/* FIXME: user may want to customize these values */
+	.spi_config.spi_config_1.read_cmd          = 0xEB,
+	.spi_config.spi_config_3.wr_cmd            = 0x38,
+	.spi_config.spi_config_1.extra_byte_mode   = QUAD_MODE,
+	.spi_config.spi_config_1.dummy_mode        = QUAD_MODE,
+	.spi_config.spi_config_1.addr_mode         = QUAD_MODE,
+	.spi_config.spi_config_1.data_mode         = QUAD_MODE,
+	.spi_config.spi_config_1.inst_mode         = QUAD_MODE,
+	.spi_config.spi_config_3.wr_addr_mode      = QUAD_MODE,
+	.spi_config.spi_config_3.wr_data_mode      = QUAD_MODE,
+	.spi_config.spi_config_3.wr_inst_mode      = QUAD_MODE,
+	.spi_config.spi_config_2.wrap_len_in_bytes = NO_WRAP,
+	.spi_config.spi_config_2.swap_en           = 1,
+	.spi_config.spi_config_2.addr_width        = 3, /* 24 bits */
+	.spi_config.spi_config_2.cs_no             = 0,
+	.spi_config.spi_config_4.secondary_csn     = 1,
+	.spi_config.spi_config_2.neg_edge_sampling = 1,
+	.spi_config.spi_config_1.no_of_dummy_bytes = 3,
+	.spi_config.spi_config_1.dummy_W_or_R      = DUMMY_READS,
+	.spi_config.spi_config_2.full_duplex       = IGNORE_FULL_DUPLEX,
+	.spi_config.spi_config_2.qspi_clk_en       = QSPI_FULL_TIME_CLK,
+	.spi_config.spi_config_1.flash_type        = 0xf,
+	.spi_config.spi_config_3.dummys_4_jump     = 1,
+	.spi_config.spi_config_4.valid_prot_bits   = 4,
+	.spi_config.spi_config_1.d3d2_data         = 0x03,
+	.spi_config.spi_config_5.d7_d4_data        = 0x0f,
+};
+/* PSRAMSecureSegments is directly referenced by sl_si91x_psram_init() */
+struct PSRAMSecureSegmentType PSRAMSecureSegments[MAX_SEC_SEGMENTS] = {
+	[0].segmentEnable = 1,
+	[0].lowerBoundary = 0x00000,
+	[0].higherBoundary = 0x0ffff,
+};
+DEVICE_DT_INST_DEFINE(0, siwx91x_memc_init, NULL, NULL, &siwx91x_memc_config,
+		      PRE_KERNEL_1, CONFIG_MEMC_INIT_PRIORITY, NULL);

dts/bindings/memory-controllers/silabs,siwx91x-qspi-memory.yaml

@@ -0,0 +1,44 @@
+description: |
+  Silicon Labs QSPI (Quad Serial Protocol Interface) memory controller.
+
+  This driver expects a children node compatible with "zephyr,memory-region".
+  The size of the PSRAM is taken from this node. It also used by Zephyr to
+  declare the area in the linker script.
+
+  Note after the chip reset, the bootloader may automatically configure the
+  Memory Controller. So, the user may be able to properly use the PSRAM without
+  this driver (in this case, only the "zephyr,memory-region" node is required).
+
+  This driver allows for non default configurations. In this case, if the users
+  want to take advantage of the automatic data relocation of Zephyr, they have
+  to tune the MEMC_INIT_PRIORITY value to initialize this driver before the
+  initialization of the kernel resources. Then, they will probably want to also
+  initialize the clock driver before this driver.
+
+  Otherwise, it is also possible to start this driver later in the boot
+  sequence, but the user will have to manage the memory region manually.
+
+include: [base.yaml, pinctrl-device.yaml]
+
+compatible: "silabs,siwx91x-qspi-memory"
+
+properties:
+  reg:
+    required: true
+
+  device-id:
+    type: uint8-array
+    required: true
+    description: |
+      Value returned by the chip on READ_ID command. An array of 8 bytes is
+      expected. However only the two first bytes (should be "Manufacturer ID"
+      and "Known Good Die") are used. The driver won't continue if the value
+      returned by the chip does not match this field.
+
+  normal-freq:
+    type: int
+    required: true
+
+  fast-freq:
+    type: int
+    required: true

include/zephyr/dt-bindings/clock/silabs/siwx91x-clock.h

@@ -14,6 +14,7 @@
 #define SIWX91X_CLK_DMA0          7
 #define SIWX91X_CLK_WATCHDOG      8
 #define SIWX91X_CLK_PWM           9
-#define SIWX91X_CLK_GSPI          10
+#define SIWX91X_CLK_GSPI         10
+#define SIWX91X_CLK_QSPI         11
 
 #endif

modules/hal_silabs/wiseconnect/CMakeLists.txt

@@ -69,6 +69,11 @@ zephyr_library_sources_ifdef(CONFIG_DMA_SILABS_SIWX91X
   ${WISECONNECT_DIR}/components/device/silabs/si91x/mcu/drivers/rom_driver/src/rsi_rom_table_si91x.c
 )
 
+zephyr_library_sources_ifdef(CONFIG_MEMC_SILABS_SIWX91X_QSPI
+  ${WISECONNECT_DIR}/components/device/silabs/si91x/mcu/drivers/unified_api/src/sl_si91x_psram.c
+  ${WISECONNECT_DIR}/components/device/silabs/si91x/mcu/drivers/peripheral_drivers/src/rsi_qspi.c
+)
+
 if(CONFIG_WIFI_SILABS_SIWX91X)
   zephyr_library_sources(
     ${WISECONNECT_DIR}/components/device/silabs/si91x/wireless/sl_net/src/sl_si91x_net_internal_stack.c

west.yml

@@ -235,7 +235,7 @@ manifest:
       groups:
         - hal
     - name: hal_silabs
-      revision: 15994d76eac4be404825fbef35a1ef1a42e4fc50
+      revision: 389726f350880238b9a1034f575ffd46c4309827
       path: modules/hal/silabs
       groups:
         - hal