1 // SPDX-License-Identifier: GPL-2.0-only
3  *  Amstrad E3 FIQ handling
10  * Parts of this code are taken from linux/arch/arm/mach-omap/irq.c
20 #include <linux/platform_data/ams-delta-fiq.h>
23 #include <asm/fiq.h>
24 #include <linux/soc/ti/omap1-io.h>
27 #include "ams-delta-fiq.h"
28 #include "board-ams-delta.h"
31 	.name	= "ams-delta-fiq"
35  * This buffer is shared between FIQ and IRQ contexts.
36  * The FIQ and IRQ isrs can both read and write it.
38  * followed by the circular buffer where the FIQ isr stores
40  * <linux/platform_data/ams-delta-fiq.h> for details of offsets.
60 	 * until the IRQ counter catches the FIQ incremented interrupt counter.  in deferred_fiq()
65 		irq_num = d->irq;  in deferred_fiq()
75 			if (!WARN_ON_ONCE(!irq_chip->irq_unmask))  in deferred_fiq()
76 				irq_chip->irq_unmask(d);  in deferred_fiq()
95 	irq_chip = chip->irq.chip;  in ams_delta_init_fiq()
98 		       chip->label);  in ams_delta_init_fiq()
114 		 * FIQ handler takes full control over serio data and clk GPIO  in ams_delta_init_fiq()
136 	fiqhandler_length = &qwerty_fiqin_end - &qwerty_fiqin_start;  in ams_delta_init_fiq()
137 	pr_info("Installing fiq handler from %p, length 0x%x\n",  in ams_delta_init_fiq()
142 		pr_err("ams_delta_init_fiq(): couldn't claim FIQ, ret=%d\n",  in ams_delta_init_fiq()
159 			((INT_DEFERRED_FIQ - NR_IRQS_LEGACY) & 0x1f) * 0x4;  in ams_delta_init_fiq()
167 	 * between FIQ mode and IRQ mode  in ams_delta_init_fiq()
186 	 * FIQ mode r9 always points to the fiq_buffer, because the FIQ isr  in ams_delta_init_fiq()
187 	 * will run in an unpredictable context. The fiq_buffer is the FIQ isr's  in ams_delta_init_fiq()
197 	 * Redirect GPIO interrupts to FIQ  in ams_delta_init_fiq()
199 	offset = IRQ_ILR0_REG_OFFSET + (INT_GPIO_BANK1 - NR_IRQS_LEGACY) * 0x4;  in ams_delta_init_fiq()
203 	/* Initialize serio device IRQ resource and platform_data */  in ams_delta_init_fiq()
204 	serio->resource[0].start = gpiod_to_irq(clk);  in ams_delta_init_fiq()
205 	serio->resource[0].end = serio->resource[0].start;  in ams_delta_init_fiq()
206 	serio->dev.platform_data = fiq_buffer;  in ams_delta_init_fiq()
209 	 * Since FIQ handler performs handling of GPIO registers for  in ams_delta_init_fiq()
212 	 * bad interaction with gpio-omap driver.  This is no longer needed  in ams_delta_init_fiq()
217 	 * of that dependency on gpio-omap driver behavior.  in ams_delta_init_fiq()