2 files changed, 237 insertions, 68 deletions

diff --git a/drivers/clocksource/sh_cmt.c b/drivers/clocksource/sh_cmt.c
index c753efcfe9f5..1efe7d64efca 100644
--- a/drivers/clocksource/sh_cmt.c
+++ b/drivers/clocksource/sh_cmt.c
@@ -53,7 +53,16 @@ struct sh_cmt_device;
  * channel registers block. All other versions have a shared start/stop register
  * located in the global space.
  *
- * Note that CMT0 on r8a73a4, r8a7790 and r8a7791, while implementing 32-bit
+ * Channels are indexed from 0 to N-1 in the documentation. The channel index
+ * infers the start/stop bit position in the control register and the channel
+ * registers block address. Some CMT instances have a subset of channels
+ * available, in which case the index in the documentation doesn't match the
+ * "real" index as implemented in hardware. This is for instance the case with
+ * CMT0 on r8a7740, which is a 32-bit variant with a single channel numbered 0
+ * in the documentation but using start/stop bit 5 and having its registers
+ * block at 0x60.
+ *
+ * Similarly CMT0 on r8a73a4, r8a7790 and r8a7791, while implementing 32-bit
  * channels only, is a 48-bit gen2 CMT with the 48-bit channels unavailable.
  */
 
@@ -85,10 +94,14 @@ struct sh_cmt_info {
 
 struct sh_cmt_channel {
 	struct sh_cmt_device *cmt;
-	unsigned int index;
 
-	void __iomem *base;
+	unsigned int index;	/* Index in the documentation */
+	unsigned int hwidx;	/* Real hardware index */
+
+	void __iomem *iostart;
+	void __iomem *ioctrl;
 
+	unsigned int timer_bit;
 	unsigned long flags;
 	unsigned long match_value;
 	unsigned long next_match_value;
@@ -105,6 +118,7 @@ struct sh_cmt_device {
 	struct platform_device *pdev;
 
 	const struct sh_cmt_info *info;
+	bool legacy;
 
 	void __iomem *mapbase_ch;
 	void __iomem *mapbase;
@@ -112,6 +126,9 @@ struct sh_cmt_device {
 
 	struct sh_cmt_channel *channels;
 	unsigned int num_channels;
+
+	bool has_clockevent;
+	bool has_clocksource;
 };
 
 #define SH_CMT16_CMCSR_CMF		(1 << 7)
@@ -223,41 +240,47 @@ static const struct sh_cmt_info sh_cmt_info[] = {
 
 static inline unsigned long sh_cmt_read_cmstr(struct sh_cmt_channel *ch)
 {
-	return ch->cmt->info->read_control(ch->cmt->mapbase, 0);
+	if (ch->iostart)
+		return ch->cmt->info->read_control(ch->iostart, 0);
+	else
+		return ch->cmt->info->read_control(ch->cmt->mapbase, 0);
 }
 
-static inline unsigned long sh_cmt_read_cmcsr(struct sh_cmt_channel *ch)
+static inline void sh_cmt_write_cmstr(struct sh_cmt_channel *ch,
+				      unsigned long value)
 {
-	return ch->cmt->info->read_control(ch->base, CMCSR);
+	if (ch->iostart)
+		ch->cmt->info->write_control(ch->iostart, 0, value);
+	else
+		ch->cmt->info->write_control(ch->cmt->mapbase, 0, value);
 }
 
-static inline unsigned long sh_cmt_read_cmcnt(struct sh_cmt_channel *ch)
+static inline unsigned long sh_cmt_read_cmcsr(struct sh_cmt_channel *ch)
 {
-	return ch->cmt->info->read_count(ch->base, CMCNT);
+	return ch->cmt->info->read_control(ch->ioctrl, CMCSR);
 }
 
-static inline void sh_cmt_write_cmstr(struct sh_cmt_channel *ch,
+static inline void sh_cmt_write_cmcsr(struct sh_cmt_channel *ch,
 				      unsigned long value)
 {
-	ch->cmt->info->write_control(ch->cmt->mapbase, 0, value);
+	ch->cmt->info->write_control(ch->ioctrl, CMCSR, value);
 }
 
-static inline void sh_cmt_write_cmcsr(struct sh_cmt_channel *ch,
-				      unsigned long value)
+static inline unsigned long sh_cmt_read_cmcnt(struct sh_cmt_channel *ch)
 {
-	ch->cmt->info->write_control(ch->base, CMCSR, value);
+	return ch->cmt->info->read_count(ch->ioctrl, CMCNT);
 }
 
 static inline void sh_cmt_write_cmcnt(struct sh_cmt_channel *ch,
 				      unsigned long value)
 {
-	ch->cmt->info->write_count(ch->base, CMCNT, value);
+	ch->cmt->info->write_count(ch->ioctrl, CMCNT, value);
 }
 
 static inline void sh_cmt_write_cmcor(struct sh_cmt_channel *ch,
 				      unsigned long value)
 {
-	ch->cmt->info->write_count(ch->base, CMCOR, value);
+	ch->cmt->info->write_count(ch->ioctrl, CMCOR, value);
 }
 
 static unsigned long sh_cmt_get_counter(struct sh_cmt_channel *ch,
@@ -286,7 +309,6 @@ static DEFINE_RAW_SPINLOCK(sh_cmt_lock);
 
 static void sh_cmt_start_stop_ch(struct sh_cmt_channel *ch, int start)
 {
-	struct sh_timer_config *cfg = ch->cmt->pdev->dev.platform_data;
 	unsigned long flags, value;
 
 	/* start stop register shared by multiple timer channels */
@@ -294,9 +316,9 @@ static void sh_cmt_start_stop_ch(struct sh_cmt_channel *ch, int start)
 	value = sh_cmt_read_cmstr(ch);
 
 	if (start)
-		value |= 1 << cfg->timer_bit;
+		value |= 1 << ch->timer_bit;
 	else
-		value &= ~(1 << cfg->timer_bit);
+		value &= ~(1 << ch->timer_bit);
 
 	sh_cmt_write_cmstr(ch, value);
 	raw_spin_unlock_irqrestore(&sh_cmt_lock, flags);
@@ -790,27 +812,72 @@ static void sh_cmt_register_clockevent(struct sh_cmt_channel *ch,
 static int sh_cmt_register(struct sh_cmt_channel *ch, const char *name,
 			   bool clockevent, bool clocksource)
 {
-	if (clockevent)
+	if (clockevent) {
+		ch->cmt->has_clockevent = true;
 		sh_cmt_register_clockevent(ch, name);
+	}
 
-	if (clocksource)
+	if (clocksource) {
+		ch->cmt->has_clocksource = true;
 		sh_cmt_register_clocksource(ch, name);
+	}
 
 	return 0;
 }
 
 static int sh_cmt_setup_channel(struct sh_cmt_channel *ch, unsigned int index,
-				struct sh_cmt_device *cmt)
+				unsigned int hwidx, bool clockevent,
+				bool clocksource, struct sh_cmt_device *cmt)
 {
-	struct sh_timer_config *cfg = cmt->pdev->dev.platform_data;
 	int irq;
 	int ret;
 
+	/* Skip unused channels. */
+	if (!clockevent && !clocksource)
+		return 0;
+
 	ch->cmt = cmt;
-	ch->base = cmt->mapbase_ch;
 	ch->index = index;
+	ch->hwidx = hwidx;
+
+	/*
+	 * Compute the address of the channel control register block. For the
+	 * timers with a per-channel start/stop register, compute its address
+	 * as well.
+	 *
+	 * For legacy configuration the address has been mapped explicitly.
+	 */
+	if (cmt->legacy) {
+		ch->ioctrl = cmt->mapbase_ch;
+	} else {
+		switch (cmt->info->model) {
+		case SH_CMT_16BIT:
+			ch->ioctrl = cmt->mapbase + 2 + ch->hwidx * 6;
+			break;
+		case SH_CMT_32BIT:
+		case SH_CMT_48BIT:
+			ch->ioctrl = cmt->mapbase + 0x10 + ch->hwidx * 0x10;
+			break;
+		case SH_CMT_32BIT_FAST:
+			/*
+			 * The 32-bit "fast" timer has a single channel at hwidx
+			 * 5 but is located at offset 0x40 instead of 0x60 for
+			 * some reason.
+			 */
+			ch->ioctrl = cmt->mapbase + 0x40;
+			break;
+		case SH_CMT_48BIT_GEN2:
+			ch->iostart = cmt->mapbase + ch->hwidx * 0x100;
+			ch->ioctrl = ch->iostart + 0x10;
+			break;
+		}
+	}
+
+	if (cmt->legacy)
+		irq = platform_get_irq(cmt->pdev, 0);
+	else
+		irq = platform_get_irq(cmt->pdev, ch->index);
 
-	irq = platform_get_irq(cmt->pdev, 0);
 	if (irq < 0) {
 		dev_err(&cmt->pdev->dev, "ch%u: failed to get irq\n",
 			ch->index);
@@ -825,9 +892,15 @@ static int sh_cmt_setup_channel(struct sh_cmt_channel *ch, unsigned int index,
 	ch->match_value = ch->max_match_value;
 	raw_spin_lock_init(&ch->lock);
 
+	if (cmt->legacy) {
+		ch->timer_bit = ch->hwidx;
+	} else {
+		ch->timer_bit = cmt->info->model == SH_CMT_48BIT_GEN2
+			      ? 0 : ch->hwidx;
+	}
+
 	ret = sh_cmt_register(ch, dev_name(&cmt->pdev->dev),
-			      cfg->clockevent_rating != 0,
-			      cfg->clocksource_rating != 0);
+			      clockevent, clocksource);
 	if (ret) {
 		dev_err(&cmt->pdev->dev, "ch%u: registration failed\n",
 			ch->index);
@@ -847,97 +920,180 @@ static int sh_cmt_setup_channel(struct sh_cmt_channel *ch, unsigned int index,
 	return 0;
 }
 
-static int sh_cmt_setup(struct sh_cmt_device *cmt, struct platform_device *pdev)
+static int sh_cmt_map_memory(struct sh_cmt_device *cmt)
 {
-	struct sh_timer_config *cfg = pdev->dev.platform_data;
-	struct resource *res, *res2;
-	int ret;
-	ret = -ENXIO;
+	struct resource *mem;
 
-	cmt->pdev = pdev;
+	mem = platform_get_resource(cmt->pdev, IORESOURCE_MEM, 0);
+	if (!mem) {
+		dev_err(&cmt->pdev->dev, "failed to get I/O memory\n");
+		return -ENXIO;
+	}
 
-	if (!cfg) {
-		dev_err(&cmt->pdev->dev, "missing platform data\n");
-		goto err0;
+	cmt->mapbase = ioremap_nocache(mem->start, resource_size(mem));
+	if (cmt->mapbase == NULL) {
+		dev_err(&cmt->pdev->dev, "failed to remap I/O memory\n");
+		return -ENXIO;
 	}
 
+	return 0;
+}
+
+static int sh_cmt_map_memory_legacy(struct sh_cmt_device *cmt)
+{
+	struct sh_timer_config *cfg = cmt->pdev->dev.platform_data;
+	struct resource *res, *res2;
+
+	/* map memory, let mapbase_ch point to our channel */
 	res = platform_get_resource(cmt->pdev, IORESOURCE_MEM, 0);
 	if (!res) {
 		dev_err(&cmt->pdev->dev, "failed to get I/O memory\n");
-		goto err0;
+		return -ENXIO;
 	}
 
-	/* optional resource for the shared timer start/stop register */
-	res2 = platform_get_resource(cmt->pdev, IORESOURCE_MEM, 1);
-
-	/* map memory, let mapbase_ch point to our channel */
 	cmt->mapbase_ch = ioremap_nocache(res->start, resource_size(res));
 	if (cmt->mapbase_ch == NULL) {
 		dev_err(&cmt->pdev->dev, "failed to remap I/O memory\n");
-		goto err0;
+		return -ENXIO;
 	}
 
+	/* optional resource for the shared timer start/stop register */
+	res2 = platform_get_resource(cmt->pdev, IORESOURCE_MEM, 1);
+
 	/* map second resource for CMSTR */
 	cmt->mapbase = ioremap_nocache(res2 ? res2->start :
 				       res->start - cfg->channel_offset,
 				       res2 ? resource_size(res2) : 2);
 	if (cmt->mapbase == NULL) {
 		dev_err(&cmt->pdev->dev, "failed to remap I/O second memory\n");
-		goto err1;
+		iounmap(cmt->mapbase_ch);
+		return -ENXIO;
 	}
 
-	/* get hold of clock */
+	/* identify the model based on the resources */
+	if (resource_size(res) == 6)
+		cmt->info = &sh_cmt_info[SH_CMT_16BIT];
+	else if (res2 && (resource_size(res2) == 4))
+		cmt->info = &sh_cmt_info[SH_CMT_48BIT_GEN2];
+	else
+		cmt->info = &sh_cmt_info[SH_CMT_32BIT];
+
+	return 0;
+}
+
+static void sh_cmt_unmap_memory(struct sh_cmt_device *cmt)
+{
+	iounmap(cmt->mapbase);
+	if (cmt->mapbase_ch)
+		iounmap(cmt->mapbase_ch);
+}
+
+static int sh_cmt_setup(struct sh_cmt_device *cmt, struct platform_device *pdev)
+{
+	struct sh_timer_config *cfg = pdev->dev.platform_data;
+	const struct platform_device_id *id = pdev->id_entry;
+	unsigned int hw_channels;
+	int ret;
+
+	memset(cmt, 0, sizeof(*cmt));
+	cmt->pdev = pdev;
+
+	if (!cfg) {
+		dev_err(&cmt->pdev->dev, "missing platform data\n");
+		return -ENXIO;
+	}
+
+	cmt->info = (const struct sh_cmt_info *)id->driver_data;
+	cmt->legacy = cmt->info ? false : true;
+
+	/* Get hold of clock. */
 	cmt->clk = clk_get(&cmt->pdev->dev, "cmt_fck");
 	if (IS_ERR(cmt->clk)) {
 		dev_err(&cmt->pdev->dev, "cannot get clock\n");
-		ret = PTR_ERR(cmt->clk);
-		goto err2;
+		return PTR_ERR(cmt->clk);
 	}
 
 	ret = clk_prepare(cmt->clk);
 	if (ret < 0)
-		goto err3;
+		goto err_clk_put;
 
-	/* identify the model based on the resources */
-	if (resource_size(res) == 6)
-		cmt->info = &sh_cmt_info[SH_CMT_16BIT];
-	else if (res2 && (resource_size(res2) == 4))
-		cmt->info = &sh_cmt_info[SH_CMT_48BIT_GEN2];
+	/*
+	 * Map the memory resource(s). We need to support both the legacy
+	 * platform device configuration (with one device per channel) and the
+	 * new version (with multiple channels per device).
+	 */
+	if (cmt->legacy)
+		ret = sh_cmt_map_memory_legacy(cmt);
 	else
-		cmt->info = &sh_cmt_info[SH_CMT_32BIT];
+		ret = sh_cmt_map_memory(cmt);
 
-	cmt->channels = kzalloc(sizeof(*cmt->channels), GFP_KERNEL);
+	if (ret < 0)
+		goto err_clk_unprepare;
+
+	/* Allocate and setup the channels. */
+	if (cmt->legacy) {
+		cmt->num_channels = 1;
+		hw_channels = 0;
+	} else {
+		cmt->num_channels = hweight8(cfg->channels_mask);
+		hw_channels = cfg->channels_mask;
+	}
+
+	cmt->channels = kzalloc(cmt->num_channels * sizeof(*cmt->channels),
+				GFP_KERNEL);
 	if (cmt->channels == NULL) {
 		ret = -ENOMEM;
-		goto err4;
+		goto err_unmap;
 	}
 
-	cmt->num_channels = 1;
+	if (cmt->legacy) {
+		ret = sh_cmt_setup_channel(&cmt->channels[0],
+					   cfg->timer_bit, cfg->timer_bit,
+					   cfg->clockevent_rating != 0,
+					   cfg->clocksource_rating != 0, cmt);
+		if (ret < 0)
+			goto err_unmap;
+	} else {
+		unsigned int mask = hw_channels;
+		unsigned int i;
 
-	ret = sh_cmt_setup_channel(&cmt->channels[0], cfg->timer_bit, cmt);
-	if (ret < 0)
-		goto err4;
+		/*
+		 * Use the first channel as a clock event device and the second
+		 * channel as a clock source. If only one channel is available
+		 * use it for both.
+		 */
+		for (i = 0; i < cmt->num_channels; ++i) {
+			unsigned int hwidx = ffs(mask) - 1;
+			bool clocksource = i == 1 || cmt->num_channels == 1;
+			bool clockevent = i == 0;
+
+			ret = sh_cmt_setup_channel(&cmt->channels[i], i, hwidx,
+						   clockevent, clocksource,
+						   cmt);
+			if (ret < 0)
+				goto err_unmap;
+
+			mask &= ~(1 << hwidx);
+		}
+	}
 
 	platform_set_drvdata(pdev, cmt);
 
 	return 0;
-err4:
+
+err_unmap:
 	kfree(cmt->channels);
+	sh_cmt_unmap_memory(cmt);
+err_clk_unprepare:
 	clk_unprepare(cmt->clk);
-err3:
+err_clk_put:
 	clk_put(cmt->clk);
-err2:
-	iounmap(cmt->mapbase);
-err1:
-	iounmap(cmt->mapbase_ch);
-err0:
 	return ret;
 }
 
 static int sh_cmt_probe(struct platform_device *pdev)
 {
 	struct sh_cmt_device *cmt = platform_get_drvdata(pdev);
-	struct sh_timer_config *cfg = pdev->dev.platform_data;
 	int ret;
 
 	if (!is_early_platform_device(pdev)) {
@@ -966,7 +1122,7 @@ static int sh_cmt_probe(struct platform_device *pdev)
 		return 0;
 
  out:
-	if (cfg->clockevent_rating || cfg->clocksource_rating)
+	if (cmt->has_clockevent || cmt->has_clocksource)
 		pm_runtime_irq_safe(&pdev->dev);
 	else
 		pm_runtime_idle(&pdev->dev);
@@ -979,12 +1135,24 @@ static int sh_cmt_remove(struct platform_device *pdev)
 	return -EBUSY; /* cannot unregister clockevent and clocksource */
 }
 
+static const struct platform_device_id sh_cmt_id_table[] = {
+	{ "sh_cmt", 0 },
+	{ "sh-cmt-16", (kernel_ulong_t)&sh_cmt_info[SH_CMT_16BIT] },
+	{ "sh-cmt-32", (kernel_ulong_t)&sh_cmt_info[SH_CMT_32BIT] },
+	{ "sh-cmt-32-fast", (kernel_ulong_t)&sh_cmt_info[SH_CMT_32BIT_FAST] },
+	{ "sh-cmt-48", (kernel_ulong_t)&sh_cmt_info[SH_CMT_48BIT] },
+	{ "sh-cmt-48-gen2", (kernel_ulong_t)&sh_cmt_info[SH_CMT_48BIT_GEN2] },
+	{ }
+};
+MODULE_DEVICE_TABLE(platform, sh_cmt_id_table);
+
 static struct platform_driver sh_cmt_device_driver = {
 	.probe		= sh_cmt_probe,
 	.remove		= sh_cmt_remove,
 	.driver		= {
 		.name	= "sh_cmt",
-	}
+	},
+	.id_table	= sh_cmt_id_table,
 };
 
 static int __init sh_cmt_init(void)
diff --git a/include/linux/sh_timer.h b/include/linux/sh_timer.h
index 4d9dcd138315..8e1e036d6d45 100644
--- a/include/linux/sh_timer.h
+++ b/include/linux/sh_timer.h
@@ -7,6 +7,7 @@ struct sh_timer_config {
 	int timer_bit;
 	unsigned long clockevent_rating;
 	unsigned long clocksource_rating;
+	unsigned int channels_mask;
 };
 
 #endif /* __SH_TIMER_H__ */