[nrf noup] drivers: spi_dw: add custom EXMIF peripheral handling

The Synopsys Designware SPI peripheral core is wrapped in hardware that
manages interrupts, power and clock. The SPI core registers are shifted
by 0x500 bytes.
Before the SPI core is used, the power and clock must be enabled by
writing to EXMIF.TASKS_START register.
Interrupts must be enabled by writing to EXMIF.INTENSET/INTENCLR
registers.

The SER register must be configured unconditionally during peripheral
setup. Otherwise, the serial transaction does not complete.

Signed-off-by: Rafał Kuźnia <[email protected]>

Author: e-rk

drivers/spi/spi_dw.c

@@ -40,6 +40,10 @@ LOG_MODULE_REGISTER(spi_dw);
 #include <zephyr/drivers/pinctrl.h>
 #endif
 
+#ifdef CONFIG_HAS_NRFX
+#include <nrfx.h>
+#endif
+
 static inline bool spi_dw_is_slave(struct spi_dw_data *spi)
 {
 	return (IS_ENABLED(CONFIG_SPI_SLAVE) &&
@@ -257,6 +261,7 @@ static int spi_dw_configure(const struct device *dev,
 		/* Baud rate and Slave select, for master only */
 		write_baudr(dev, SPI_DW_CLK_DIVIDER(info->clock_frequency,
 						    config->frequency));
+		write_ser(dev, BIT(config->slave));
 	}
 
 	if (spi_dw_is_slave(spi)) {
@@ -499,6 +504,10 @@ void spi_dw_isr(const struct device *dev)
 	uint32_t int_status;
 	int error;
 
+#ifdef CONFIG_HAS_NRFX
+	NRF_EXMIF->EVENTS_CORE = 0;
+#endif
+
 	int_status = read_isr(dev);
 
 	LOG_DBG("SPI %p int_status 0x%x - (tx: %d, rx: %d)", dev, int_status,
@@ -544,6 +553,11 @@ int spi_dw_init(const struct device *dev)
 
 	DEVICE_MMIO_MAP(dev, K_MEM_CACHE_NONE);
 
+#ifdef CONFIG_HAS_NRFX
+	NRF_EXMIF->INTENSET = BIT(0);
+	NRF_EXMIF->TASKS_START = 1;
+#endif
+
 	info->config_func();
 
 	/* Masking interrupt and making sure controller is disabled */
@@ -562,6 +576,11 @@ int spi_dw_init(const struct device *dev)
 	return 0;
 }
 
+#define REG_ADDR(inst) \
+	COND_CODE_1(DT_NODE_HAS_COMPAT(DT_DRV_INST(inst), nordic_nrf_exmif), \
+		    (Z_DEVICE_MMIO_NAMED_ROM_INITIALIZER(core, DT_DRV_INST(inst))), \
+		    (DEVICE_MMIO_ROM_INIT(DT_DRV_INST(inst))))
+
 #define SPI_CFG_IRQS_SINGLE_ERR_LINE(inst)					\
 		IRQ_CONNECT(DT_INST_IRQ_BY_NAME(inst, rx_avail, irq),		\
 			    DT_INST_IRQ_BY_NAME(inst, rx_avail, priority),	\
@@ -634,7 +653,7 @@ COND_CODE_1(IS_EQ(DT_NUM_IRQS(DT_DRV_INST(inst)), 1),              \
 		SPI_CONTEXT_CS_GPIOS_INITIALIZE(DT_DRV_INST(inst), ctx)                     \
 	};                                                                                  \
 	static const struct spi_dw_config spi_dw_config_##inst = {                          \
-		DEVICE_MMIO_ROM_INIT(DT_DRV_INST(inst)),                                    \
+		REG_ADDR(inst),                                                             \
 		.clock_frequency = COND_CODE_1(                                             \
 			DT_NODE_HAS_PROP(DT_INST_PHANDLE(inst, clocks), clock_frequency),   \
 			(DT_INST_PROP_BY_PHANDLE(inst, clocks, clock_frequency)),           \