OMAPDSS: move irq handling to dispc-compat

The whole dispc irq handling system we currently have is only needed for
compat layer, and thus can be moved from dispc.c to the compat layer.

This is quite straigtforward, but we need to add new dispc functions to
request and free the actual hardware irq: dispc_request_irq() and
dispc_free_irq().

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

1 files changed, 430 insertions, 0 deletions

diff --git a/drivers/video/omap2/dss/dispc-compat.c b/drivers/video/omap2/dss/dispc-compat.c
index 24e1d5e..928884c 100644
--- a/drivers/video/omap2/dss/dispc-compat.c
+++ b/drivers/video/omap2/dss/dispc-compat.c
@@ -23,6 +23,8 @@
 #include <linux/spinlock.h>
 #include <linux/jiffies.h>
 #include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/seq_file.h>
 
 #include <video/omapdss.h>
 
@@ -30,6 +32,434 @@
 #include "dss_features.h"
 #include "dispc-compat.h"
 
+#define DISPC_IRQ_MASK_ERROR            (DISPC_IRQ_GFX_FIFO_UNDERFLOW | \
+					 DISPC_IRQ_OCP_ERR | \
+					 DISPC_IRQ_VID1_FIFO_UNDERFLOW | \
+					 DISPC_IRQ_VID2_FIFO_UNDERFLOW | \
+					 DISPC_IRQ_SYNC_LOST | \
+					 DISPC_IRQ_SYNC_LOST_DIGIT)
+
+#define DISPC_MAX_NR_ISRS		8
+
+struct omap_dispc_isr_data {
+	omap_dispc_isr_t	isr;
+	void			*arg;
+	u32			mask;
+};
+
+struct dispc_irq_stats {
+	unsigned long last_reset;
+	unsigned irq_count;
+	unsigned irqs[32];
+};
+
+static struct {
+	spinlock_t irq_lock;
+	u32 irq_error_mask;
+	struct omap_dispc_isr_data registered_isr[DISPC_MAX_NR_ISRS];
+	u32 error_irqs;
+	struct work_struct error_work;
+
+#ifdef CONFIG_OMAP2_DSS_COLLECT_IRQ_STATS
+	spinlock_t irq_stats_lock;
+	struct dispc_irq_stats irq_stats;
+#endif
+} dispc_compat;
+
+
+#ifdef CONFIG_OMAP2_DSS_COLLECT_IRQ_STATS
+static void dispc_dump_irqs(struct seq_file *s)
+{
+	unsigned long flags;
+	struct dispc_irq_stats stats;
+
+	spin_lock_irqsave(&dispc_compat.irq_stats_lock, flags);
+
+	stats = dispc_compat.irq_stats;
+	memset(&dispc_compat.irq_stats, 0, sizeof(dispc_compat.irq_stats));
+	dispc_compat.irq_stats.last_reset = jiffies;
+
+	spin_unlock_irqrestore(&dispc_compat.irq_stats_lock, flags);
+
+	seq_printf(s, "period %u ms\n",
+			jiffies_to_msecs(jiffies - stats.last_reset));
+
+	seq_printf(s, "irqs %d\n", stats.irq_count);
+#define PIS(x) \
+	seq_printf(s, "%-20s %10d\n", #x, stats.irqs[ffs(DISPC_IRQ_##x)-1]);
+
+	PIS(FRAMEDONE);
+	PIS(VSYNC);
+	PIS(EVSYNC_EVEN);
+	PIS(EVSYNC_ODD);
+	PIS(ACBIAS_COUNT_STAT);
+	PIS(PROG_LINE_NUM);
+	PIS(GFX_FIFO_UNDERFLOW);
+	PIS(GFX_END_WIN);
+	PIS(PAL_GAMMA_MASK);
+	PIS(OCP_ERR);
+	PIS(VID1_FIFO_UNDERFLOW);
+	PIS(VID1_END_WIN);
+	PIS(VID2_FIFO_UNDERFLOW);
+	PIS(VID2_END_WIN);
+	if (dss_feat_get_num_ovls() > 3) {
+		PIS(VID3_FIFO_UNDERFLOW);
+		PIS(VID3_END_WIN);
+	}
+	PIS(SYNC_LOST);
+	PIS(SYNC_LOST_DIGIT);
+	PIS(WAKEUP);
+	if (dss_has_feature(FEAT_MGR_LCD2)) {
+		PIS(FRAMEDONE2);
+		PIS(VSYNC2);
+		PIS(ACBIAS_COUNT_STAT2);
+		PIS(SYNC_LOST2);
+	}
+	if (dss_has_feature(FEAT_MGR_LCD3)) {
+		PIS(FRAMEDONE3);
+		PIS(VSYNC3);
+		PIS(ACBIAS_COUNT_STAT3);
+		PIS(SYNC_LOST3);
+	}
+#undef PIS
+}
+#endif
+
+/* dispc.irq_lock has to be locked by the caller */
+static void _omap_dispc_set_irqs(void)
+{
+	u32 mask;
+	int i;
+	struct omap_dispc_isr_data *isr_data;
+
+	mask = dispc_compat.irq_error_mask;
+
+	for (i = 0; i < DISPC_MAX_NR_ISRS; i++) {
+		isr_data = &dispc_compat.registered_isr[i];
+
+		if (isr_data->isr == NULL)
+			continue;
+
+		mask |= isr_data->mask;
+	}
+
+	dispc_write_irqenable(mask);
+}
+
+int omap_dispc_register_isr(omap_dispc_isr_t isr, void *arg, u32 mask)
+{
+	int i;
+	int ret;
+	unsigned long flags;
+	struct omap_dispc_isr_data *isr_data;
+
+	if (isr == NULL)
+		return -EINVAL;
+
+	spin_lock_irqsave(&dispc_compat.irq_lock, flags);
+
+	/* check for duplicate entry */
+	for (i = 0; i < DISPC_MAX_NR_ISRS; i++) {
+		isr_data = &dispc_compat.registered_isr[i];
+		if (isr_data->isr == isr && isr_data->arg == arg &&
+				isr_data->mask == mask) {
+			ret = -EINVAL;
+			goto err;
+		}
+	}
+
+	isr_data = NULL;
+	ret = -EBUSY;
+
+	for (i = 0; i < DISPC_MAX_NR_ISRS; i++) {
+		isr_data = &dispc_compat.registered_isr[i];
+
+		if (isr_data->isr != NULL)
+			continue;
+
+		isr_data->isr = isr;
+		isr_data->arg = arg;
+		isr_data->mask = mask;
+		ret = 0;
+
+		break;
+	}
+
+	if (ret)
+		goto err;
+
+	_omap_dispc_set_irqs();
+
+	spin_unlock_irqrestore(&dispc_compat.irq_lock, flags);
+
+	return 0;
+err:
+	spin_unlock_irqrestore(&dispc_compat.irq_lock, flags);
+
+	return ret;
+}
+EXPORT_SYMBOL(omap_dispc_register_isr);
+
+int omap_dispc_unregister_isr(omap_dispc_isr_t isr, void *arg, u32 mask)
+{
+	int i;
+	unsigned long flags;
+	int ret = -EINVAL;
+	struct omap_dispc_isr_data *isr_data;
+
+	spin_lock_irqsave(&dispc_compat.irq_lock, flags);
+
+	for (i = 0; i < DISPC_MAX_NR_ISRS; i++) {
+		isr_data = &dispc_compat.registered_isr[i];
+		if (isr_data->isr != isr || isr_data->arg != arg ||
+				isr_data->mask != mask)
+			continue;
+
+		/* found the correct isr */
+
+		isr_data->isr = NULL;
+		isr_data->arg = NULL;
+		isr_data->mask = 0;
+
+		ret = 0;
+		break;
+	}
+
+	if (ret == 0)
+		_omap_dispc_set_irqs();
+
+	spin_unlock_irqrestore(&dispc_compat.irq_lock, flags);
+
+	return ret;
+}
+EXPORT_SYMBOL(omap_dispc_unregister_isr);
+
+static void print_irq_status(u32 status)
+{
+	if ((status & dispc_compat.irq_error_mask) == 0)
+		return;
+
+#define PIS(x) (status & DISPC_IRQ_##x) ? (#x " ") : ""
+
+	pr_debug("DISPC IRQ: 0x%x: %s%s%s%s%s%s%s%s%s\n",
+		status,
+		PIS(OCP_ERR),
+		PIS(GFX_FIFO_UNDERFLOW),
+		PIS(VID1_FIFO_UNDERFLOW),
+		PIS(VID2_FIFO_UNDERFLOW),
+		dss_feat_get_num_ovls() > 3 ? PIS(VID3_FIFO_UNDERFLOW) : "",
+		PIS(SYNC_LOST),
+		PIS(SYNC_LOST_DIGIT),
+		dss_has_feature(FEAT_MGR_LCD2) ? PIS(SYNC_LOST2) : "",
+		dss_has_feature(FEAT_MGR_LCD3) ? PIS(SYNC_LOST3) : "");
+#undef PIS
+}
+
+/* Called from dss.c. Note that we don't touch clocks here,
+ * but we presume they are on because we got an IRQ. However,
+ * an irq handler may turn the clocks off, so we may not have
+ * clock later in the function. */
+static irqreturn_t omap_dispc_irq_handler(int irq, void *arg)
+{
+	int i;
+	u32 irqstatus, irqenable;
+	u32 handledirqs = 0;
+	u32 unhandled_errors;
+	struct omap_dispc_isr_data *isr_data;
+	struct omap_dispc_isr_data registered_isr[DISPC_MAX_NR_ISRS];
+
+	spin_lock(&dispc_compat.irq_lock);
+
+	irqstatus = dispc_read_irqstatus();
+	irqenable = dispc_read_irqenable();
+
+	/* IRQ is not for us */
+	if (!(irqstatus & irqenable)) {
+		spin_unlock(&dispc_compat.irq_lock);
+		return IRQ_NONE;
+	}
+
+#ifdef CONFIG_OMAP2_DSS_COLLECT_IRQ_STATS
+	spin_lock(&dispc_compat.irq_stats_lock);
+	dispc_compat.irq_stats.irq_count++;
+	dss_collect_irq_stats(irqstatus, dispc_compat.irq_stats.irqs);
+	spin_unlock(&dispc_compat.irq_stats_lock);
+#endif
+
+	print_irq_status(irqstatus);
+
+	/* Ack the interrupt. Do it here before clocks are possibly turned
+	 * off */
+	dispc_clear_irqstatus(irqstatus);
+	/* flush posted write */
+	dispc_read_irqstatus();
+
+	/* make a copy and unlock, so that isrs can unregister
+	 * themselves */
+	memcpy(registered_isr, dispc_compat.registered_isr,
+			sizeof(registered_isr));
+
+	spin_unlock(&dispc_compat.irq_lock);
+
+	for (i = 0; i < DISPC_MAX_NR_ISRS; i++) {
+		isr_data = &registered_isr[i];
+
+		if (!isr_data->isr)
+			continue;
+
+		if (isr_data->mask & irqstatus) {
+			isr_data->isr(isr_data->arg, irqstatus);
+			handledirqs |= isr_data->mask;
+		}
+	}
+
+	spin_lock(&dispc_compat.irq_lock);
+
+	unhandled_errors = irqstatus & ~handledirqs & dispc_compat.irq_error_mask;
+
+	if (unhandled_errors) {
+		dispc_compat.error_irqs |= unhandled_errors;
+
+		dispc_compat.irq_error_mask &= ~unhandled_errors;
+		_omap_dispc_set_irqs();
+
+		schedule_work(&dispc_compat.error_work);
+	}
+
+	spin_unlock(&dispc_compat.irq_lock);
+
+	return IRQ_HANDLED;
+}
+
+static void dispc_error_worker(struct work_struct *work)
+{
+	int i;
+	u32 errors;
+	unsigned long flags;
+	static const unsigned fifo_underflow_bits[] = {
+		DISPC_IRQ_GFX_FIFO_UNDERFLOW,
+		DISPC_IRQ_VID1_FIFO_UNDERFLOW,
+		DISPC_IRQ_VID2_FIFO_UNDERFLOW,
+		DISPC_IRQ_VID3_FIFO_UNDERFLOW,
+	};
+
+	spin_lock_irqsave(&dispc_compat.irq_lock, flags);
+	errors = dispc_compat.error_irqs;
+	dispc_compat.error_irqs = 0;
+	spin_unlock_irqrestore(&dispc_compat.irq_lock, flags);
+
+	dispc_runtime_get();
+
+	for (i = 0; i < omap_dss_get_num_overlays(); ++i) {
+		struct omap_overlay *ovl;
+		unsigned bit;
+
+		ovl = omap_dss_get_overlay(i);
+		bit = fifo_underflow_bits[i];
+
+		if (bit & errors) {
+			DSSERR("FIFO UNDERFLOW on %s, disabling the overlay\n",
+					ovl->name);
+			dispc_ovl_enable(ovl->id, false);
+			dispc_mgr_go(ovl->manager->id);
+			msleep(50);
+		}
+	}
+
+	for (i = 0; i < omap_dss_get_num_overlay_managers(); ++i) {
+		struct omap_overlay_manager *mgr;
+		unsigned bit;
+
+		mgr = omap_dss_get_overlay_manager(i);
+		bit = dispc_mgr_get_sync_lost_irq(i);
+
+		if (bit & errors) {
+			int j;
+
+			DSSERR("SYNC_LOST on channel %s, restarting the output "
+					"with video overlays disabled\n",
+					mgr->name);
+
+			dss_mgr_disable(mgr);
+
+			for (j = 0; j < omap_dss_get_num_overlays(); ++j) {
+				struct omap_overlay *ovl;
+				ovl = omap_dss_get_overlay(j);
+
+				if (ovl->id != OMAP_DSS_GFX &&
+						ovl->manager == mgr)
+					ovl->disable(ovl);
+			}
+
+			dss_mgr_enable(mgr);
+		}
+	}
+
+	if (errors & DISPC_IRQ_OCP_ERR) {
+		DSSERR("OCP_ERR\n");
+		for (i = 0; i < omap_dss_get_num_overlay_managers(); ++i) {
+			struct omap_overlay_manager *mgr;
+
+			mgr = omap_dss_get_overlay_manager(i);
+			dss_mgr_disable(mgr);
+		}
+	}
+
+	spin_lock_irqsave(&dispc_compat.irq_lock, flags);
+	dispc_compat.irq_error_mask |= errors;
+	_omap_dispc_set_irqs();
+	spin_unlock_irqrestore(&dispc_compat.irq_lock, flags);
+
+	dispc_runtime_put();
+}
+
+int dss_dispc_initialize_irq(void)
+{
+	int r;
+
+#ifdef CONFIG_OMAP2_DSS_COLLECT_IRQ_STATS
+	spin_lock_init(&dispc_compat.irq_stats_lock);
+	dispc_compat.irq_stats.last_reset = jiffies;
+	dss_debugfs_create_file("dispc_irq", dispc_dump_irqs);
+#endif
+
+	spin_lock_init(&dispc_compat.irq_lock);
+
+	memset(dispc_compat.registered_isr, 0,
+			sizeof(dispc_compat.registered_isr));
+
+	dispc_compat.irq_error_mask = DISPC_IRQ_MASK_ERROR;
+	if (dss_has_feature(FEAT_MGR_LCD2))
+		dispc_compat.irq_error_mask |= DISPC_IRQ_SYNC_LOST2;
+	if (dss_has_feature(FEAT_MGR_LCD3))
+		dispc_compat.irq_error_mask |= DISPC_IRQ_SYNC_LOST3;
+	if (dss_feat_get_num_ovls() > 3)
+		dispc_compat.irq_error_mask |= DISPC_IRQ_VID3_FIFO_UNDERFLOW;
+
+	/*
+	 * there's SYNC_LOST_DIGIT waiting after enabling the DSS,
+	 * so clear it
+	 */
+	dispc_clear_irqstatus(dispc_read_irqstatus());
+
+	INIT_WORK(&dispc_compat.error_work, dispc_error_worker);
+
+	_omap_dispc_set_irqs();
+
+	r = dispc_request_irq(omap_dispc_irq_handler, &dispc_compat);
+	if (r) {
+		DSSERR("dispc_request_irq failed\n");
+		return r;
+	}
+
+	return 0;
+}
+
+void dss_dispc_uninitialize_irq(void)
+{
+	dispc_free_irq(&dispc_compat);
+}
+
 static void dispc_mgr_disable_isr(void *data, u32 mask)
 {
 	struct completion *compl = data;