gta02: Add fiq handler

5 files changed, 143 insertions, 10 deletions

diff --git a/arch/arm/mach-s3c2442/Kconfig b/arch/arm/mach-s3c2442/Kconfig
index 550f6492f32..8e37b9f42ab 100644
--- a/arch/arm/mach-s3c2442/Kconfig
+++ b/arch/arm/mach-s3c2442/Kconfig
@@ -34,6 +34,8 @@ config MACH_NEO1973_GTA02
 	select MACH_NEO1973
 	select S3C2410_PWM
 	select S3C_DEV_USB_HOST
+	select FIQ
+	select S3C_PWM
 	select S3C24XX_GPIO_EXTRA64
 	help
 	   Say Y here if you are using the Openmoko GTA02 / Freerunner GSM Phone
diff --git a/arch/arm/mach-s3c2442/Makefile b/arch/arm/mach-s3c2442/Makefile
index 2a19113a576..87338d9e139 100644
--- a/arch/arm/mach-s3c2442/Makefile
+++ b/arch/arm/mach-s3c2442/Makefile
@@ -12,7 +12,7 @@ obj-				:=
 obj-$(CONFIG_CPU_S3C2442)	+= s3c2442.o
 obj-$(CONFIG_CPU_S3C2442)	+= clock.o
 
-obj-$(CONFIG_MACH_NEO1973_GTA02) += mach-gta02.o
-
+obj-$(CONFIG_MACH_NEO1973_GTA02) += mach-gta02.o \
+	gta02-fiq.o
 # Machine support
 
diff --git a/arch/arm/mach-s3c2442/gta02-fiq.c b/arch/arm/mach-s3c2442/gta02-fiq.c
new file mode 100644
index 00000000000..78a6501d5be
--- /dev/null
+++ b/arch/arm/mach-s3c2442/gta02-fiq.c
@@ -0,0 +1,126 @@
+#include <linux/kernel.h>
+
+#include <asm/fiq.h>
+#include <mach/regs-irq.h>
+#include <plat/regs-timer.h>
+#include <mach/irqs.h>
+#include <linux/io.h>
+#include <linux/pwm.h>
+#include <linux/err.h>
+
+/* -------------------------------------------------------------------------------
+ * GTA02 FIQ related
+ *
+ * Calls into vibrator and hdq and based on the return values
+ * determines if we the FIQ source be kept alive
+ */
+
+#define DIVISOR_FROM_US(x) ((x) << 3)
+
+/* Global data related to our fiq source */
+static uint32_t gta02_fiq_ack_mask;
+static const int gta02_gta02_fiq_timer_id = 2;
+
+struct pwm_device* gta02_fiq_timer;
+
+void gta02_fiq_handler(void)
+{
+	unsigned long intmask;
+	int keep_running = 0;
+	/* disable further timer interrupts if nobody has any work
+	 * or adjust rate according to who still has work
+	 *
+	 * CAUTION: it means forground code must disable FIQ around
+	 * its own non-atomic S3C2410_INTMSK changes... not common
+	 * thankfully and taken care of by the fiq-basis patch
+	 */
+
+	if (!keep_running) {
+		/* Disable irq */
+		intmask = __raw_readl(S3C2410_INTMSK);
+		intmask |= (gta02_fiq_ack_mask);
+		__raw_writel(intmask, S3C2410_INTMSK);
+	}
+
+	__raw_writel(gta02_fiq_ack_mask, S3C2410_SRCPND);
+}
+
+void gta02_fiq_kick(void)
+{
+	unsigned long flags;
+	unsigned long intmask;
+	/* we have to take care about FIQ because this modification is
+	 * non-atomic, FIQ could come in after the read and before the
+	 * writeback and its changes to the register would be lost
+	 * (platform INTMSK mod code is taken care of already)
+	 */
+	local_save_flags(flags);
+	local_fiq_disable();
+
+	/* allow FIQs to resume */
+	intmask = __raw_readl(S3C2410_INTMSK);
+	intmask &= ~(gta02_fiq_ack_mask);
+	__raw_writel(intmask, S3C2410_INTMSK);
+
+	local_irq_restore(flags);
+
+}
+
+int gta02_fiq_enable(void)
+{
+	int ret = 0;
+
+	local_fiq_disable();
+
+	gta02_fiq_timer = pwm_request(gta02_gta02_fiq_timer_id, "fiq timer");
+
+	if (IS_ERR(gta02_fiq_timer)) {
+		ret = PTR_ERR(gta02_fiq_timer);
+		printk("GTA02 FIQ: Could not request fiq timer: %d\n", ret);
+		return ret;
+	}
+
+	gta02_fiq_ack_mask = 1 << (IRQ_TIMER0 + gta02_gta02_fiq_timer_id
+					- S3C2410_CPUIRQ_OFFSET);
+
+
+	ret = pwm_config(gta02_fiq_timer, HDQ_SAMPLE_PERIOD_US * 1000,
+					HDQ_SAMPLE_PERIOD_US * 1000);
+	if (ret) {
+		printk("GTA02 FIQ: Could not configure fiq timer: %d\n", ret);
+		goto err;
+	}
+
+	set_fiq_c_handler(gta02_fiq_handler);
+
+	__raw_writel(gta02_fiq_ack_mask, S3C2410_INTMOD);
+
+	pwm_enable(gta02_fiq_timer);
+
+	local_fiq_enable();
+
+	return 0;
+
+err:
+	pwm_free(gta02_fiq_timer);
+
+	return ret;
+}
+
+void gta02_fiq_disable(void)
+{
+	local_fiq_disable();
+
+	if (!gta02_fiq_timer)
+		return;
+
+	__raw_writel(0, S3C2410_INTMOD);
+	set_fiq_c_handler(NULL);
+
+	pwm_disable(gta02_fiq_timer);
+
+	pwm_free(gta02_fiq_timer);
+
+	gta02_fiq_timer = NULL;
+}
+/* -------------------- /GTA02 FIQ Handler ------------------------------------- */
diff --git a/arch/arm/mach-s3c2442/include/mach/gta02-fiq.h b/arch/arm/mach-s3c2442/include/mach/gta02-fiq.h
new file mode 100644
index 00000000000..90de3530595
--- /dev/null
+++ b/arch/arm/mach-s3c2442/include/mach/gta02-fiq.h
@@ -0,0 +1,9 @@
+#ifndef __GTA02_FIQ_H
+#define __GTA02_FIQ_H
+
+extern void gta02_fiq_handler(void);
+extern void gta02_fiq_kick(void);
+extern int gta02_fiq_enable(void);
+extern void gta02_fiq_disable(void);
+
+#endif
diff --git a/arch/arm/mach-s3c2442/mach-gta02.c b/arch/arm/mach-s3c2442/mach-gta02.c
index eb4e215f473..d347f3724bb 100644
--- a/arch/arm/mach-s3c2442/mach-gta02.c
+++ b/arch/arm/mach-s3c2442/mach-gta02.c
@@ -92,7 +92,9 @@
 #include <linux/glamofb.h>
 #include <linux/mfd/glamo.h>
 
-static struct pcf50633 *gta02_pcf;
+#include <mach/gta02-fiq.h>
+
+struct pcf50633 *gta02_pcf;
 
 /*
  * This gets called every 1ms when we paniced.
@@ -529,12 +531,6 @@ static struct platform_device gta02_nor_flash = {
 	.num_resources	= 1,
 };
 
-
-struct platform_device s3c24xx_pwm_device = {
-	.name		= "s3c24xx_pwm",
-	.num_resources	= 0,
-};
-
 static struct i2c_board_info gta02_i2c_devs[] __initdata = {
 	{
 		I2C_BOARD_INFO("pcf50633", 0x73),
@@ -721,7 +717,7 @@ static struct platform_device *gta02_devices[] __initdata = {
 	&s3c_device_usbgadget,
 	&s3c_device_nand,
 	&gta02_nor_flash,
-	&s3c24xx_pwm_device,
+	&s3c_device_timer,
 	&s3c_device_iis,
 	&s3c_device_i2c0,
 };