arm: socfpga: Add socfpga_spim_enable() to reset_manager.c

This function will be needed by the upcoming Designware master SPI
driver. As the SPI master controller is held in reset by the current
Preloader implementation. So we need to release the reset for the
driver to communicate with the controller.

This function is called from arch_early_init_r() if the SPI
driver is enabled.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Chin Liang See <clsee@altera.com>
Cc: Dinh Nguyen <dinguyen@altera.com>
Cc: Vince Bridgers <vbridger@altera.com>
Cc: Marek Vasut <marex@denx.de>
Cc: Pavel Machek <pavel@denx.de>

arch/arm/cpu/armv7/socfpga/misc.c

@@ -202,6 +202,12 @@ int arch_early_init_r(void)
 
 	/* Add device descriptor to FPGA device table */
 	socfpga_fpga_add();
+
+#ifdef CONFIG_DESIGNWARE_SPI
+	/* Get Designware SPI controller out of reset */
+	socfpga_spim_enable();
+#endif
+
 	return 0;
 }
 

arch/arm/cpu/armv7/socfpga/reset_manager.c

@@ -104,3 +104,12 @@ void socfpga_emac_reset(int enable)
 #endif
 	}
 }
+
+/* SPI Master enable (its held in reset by the preloader) */
+void socfpga_spim_enable(void)
+{
+	const void *reset = &reset_manager_base->per_mod_reset;
+
+	clrbits_le32(reset, 1 << RSTMGR_PERMODRST_SPIM0_LSB);
+	clrbits_le32(reset, 1 << RSTMGR_PERMODRST_SPIM1_LSB);
+}

arch/arm/include/asm/arch-socfpga/reset_manager.h

@@ -14,6 +14,7 @@ void socfpga_bridges_reset(int enable);
 
 void socfpga_emac_reset(int enable);
 void socfpga_watchdog_reset(void);
+void socfpga_spim_enable(void);
 
 struct socfpga_reset_manager {
 	u32	status;
@@ -35,5 +36,7 @@ struct socfpga_reset_manager {
 #define RSTMGR_PERMODRST_EMAC0_LSB	0
 #define RSTMGR_PERMODRST_EMAC1_LSB	1
 #define RSTMGR_PERMODRST_L4WD0_LSB	6
+#define RSTMGR_PERMODRST_SPIM0_LSB	18
+#define RSTMGR_PERMODRST_SPIM1_LSB	19
 
 #endif /* _RESET_MANAGER_H_ */