Merge tag 'drm/tegra/for-4.12-rc1' of git://anongit.freedesktop.org/tegra/linux into drm-next

drm/tegra: Changes for v4.12-rc1

This contains various fixes to the host1x driver as well as a plug for a
leak of kernel pointers to userspace.

A fairly big addition this time around is the Video Image Composer (VIC)
support that can be used to accelerate some 2D and image compositing
operations.

Furthermore the driver now supports FB modifiers, so we no longer rely
on a custom IOCTL to set those.

Finally this contains a few preparatory patches for Tegra186 support
which unfortunately didn't quite make it this time, but will hopefully
be ready for v4.13.

* tag 'drm/tegra/for-4.12-rc1' of git://anongit.freedesktop.org/tegra/linux:
  gpu: host1x: Fix host1x driver shutdown
  gpu: host1x: Support module reset
  gpu: host1x: Sort includes alphabetically
  drm/tegra: Add VIC support
  dt-bindings: Add bindings for the Tegra VIC
  drm/tegra: Add falcon helper library
  drm/tegra: Add Tegra DRM allocation API
  drm/tegra: Add tiling FB modifiers
  drm/tegra: Don't leak kernel pointer to userspace
  drm/tegra: Protect IOMMU operations by mutex
  drm/tegra: Enable IOVA API when IOMMU support is enabled
  gpu: host1x: Add IOMMU support
  gpu: host1x: Fix potential out-of-bounds access
  iommu/iova: Fix compile error with CONFIG_IOMMU_IOVA=m
  iommu: Add dummy implementations for !IOMMU_IOVA
  MAINTAINERS: Add related headers to IOMMU section
  iommu/iova: Consolidate code for adding new node to iovad domain rbtree

9 files changed, 243 insertions, 86 deletions

diff --git a/drivers/gpu/host1x/bus.c b/drivers/gpu/host1x/bus.c
index eeb021fe6410..561831e1ae2c 100644
--- a/drivers/gpu/host1x/bus.c
+++ b/drivers/gpu/host1x/bus.c
@@ -267,37 +267,6 @@ static int host1x_device_match(struct device *dev, struct device_driver *drv)
 	return strcmp(dev_name(dev), drv->name) == 0;
 }
 
-static int host1x_device_probe(struct device *dev)
-{
-	struct host1x_driver *driver = to_host1x_driver(dev->driver);
-	struct host1x_device *device = to_host1x_device(dev);
-
-	if (driver->probe)
-		return driver->probe(device);
-
-	return 0;
-}
-
-static int host1x_device_remove(struct device *dev)
-{
-	struct host1x_driver *driver = to_host1x_driver(dev->driver);
-	struct host1x_device *device = to_host1x_device(dev);
-
-	if (driver->remove)
-		return driver->remove(device);
-
-	return 0;
-}
-
-static void host1x_device_shutdown(struct device *dev)
-{
-	struct host1x_driver *driver = to_host1x_driver(dev->driver);
-	struct host1x_device *device = to_host1x_device(dev);
-
-	if (driver->shutdown)
-		driver->shutdown(device);
-}
-
 static const struct dev_pm_ops host1x_device_pm_ops = {
 	.suspend = pm_generic_suspend,
 	.resume = pm_generic_resume,
@@ -310,9 +279,6 @@ static const struct dev_pm_ops host1x_device_pm_ops = {
 struct bus_type host1x_bus_type = {
 	.name = "host1x",
 	.match = host1x_device_match,
-	.probe = host1x_device_probe,
-	.remove = host1x_device_remove,
-	.shutdown = host1x_device_shutdown,
 	.pm = &host1x_device_pm_ops,
 };
 
@@ -516,6 +482,37 @@ int host1x_unregister(struct host1x *host1x)
 	return 0;
 }
 
+static int host1x_device_probe(struct device *dev)
+{
+	struct host1x_driver *driver = to_host1x_driver(dev->driver);
+	struct host1x_device *device = to_host1x_device(dev);
+
+	if (driver->probe)
+		return driver->probe(device);
+
+	return 0;
+}
+
+static int host1x_device_remove(struct device *dev)
+{
+	struct host1x_driver *driver = to_host1x_driver(dev->driver);
+	struct host1x_device *device = to_host1x_device(dev);
+
+	if (driver->remove)
+		return driver->remove(device);
+
+	return 0;
+}
+
+static void host1x_device_shutdown(struct device *dev)
+{
+	struct host1x_driver *driver = to_host1x_driver(dev->driver);
+	struct host1x_device *device = to_host1x_device(dev);
+
+	if (driver->shutdown)
+		driver->shutdown(device);
+}
+
 int host1x_driver_register_full(struct host1x_driver *driver,
 				struct module *owner)
 {
@@ -536,6 +533,9 @@ int host1x_driver_register_full(struct host1x_driver *driver,
 
 	driver->driver.bus = &host1x_bus_type;
 	driver->driver.owner = owner;
+	driver->driver.probe = host1x_device_probe;
+	driver->driver.remove = host1x_device_remove;
+	driver->driver.shutdown = host1x_device_shutdown;
 
 	return driver_register(&driver->driver);
 }
diff --git a/drivers/gpu/host1x/cdma.c b/drivers/gpu/host1x/cdma.c
index c5d82a8a2ec9..28541b280739 100644
--- a/drivers/gpu/host1x/cdma.c
+++ b/drivers/gpu/host1x/cdma.c
@@ -51,9 +51,15 @@ static void host1x_pushbuffer_destroy(struct push_buffer *pb)
 	struct host1x_cdma *cdma = pb_to_cdma(pb);
 	struct host1x *host1x = cdma_to_host1x(cdma);
 
-	if (pb->phys != 0)
-		dma_free_wc(host1x->dev, pb->size_bytes + 4, pb->mapped,
-			    pb->phys);
+	if (!pb->phys)
+		return;
+
+	if (host1x->domain) {
+		iommu_unmap(host1x->domain, pb->dma, pb->alloc_size);
+		free_iova(&host1x->iova, iova_pfn(&host1x->iova, pb->dma));
+	}
+
+	dma_free_wc(host1x->dev, pb->alloc_size, pb->mapped, pb->phys);
 
 	pb->mapped = NULL;
 	pb->phys = 0;
@@ -66,28 +72,64 @@ static int host1x_pushbuffer_init(struct push_buffer *pb)
 {
 	struct host1x_cdma *cdma = pb_to_cdma(pb);
 	struct host1x *host1x = cdma_to_host1x(cdma);
+	struct iova *alloc;
+	u32 size;
+	int err;
 
 	pb->mapped = NULL;
 	pb->phys = 0;
-	pb->size_bytes = HOST1X_PUSHBUFFER_SLOTS * 8;
+	pb->size = HOST1X_PUSHBUFFER_SLOTS * 8;
+
+	size = pb->size + 4;
 
 	/* initialize buffer pointers */
-	pb->fence = pb->size_bytes - 8;
+	pb->fence = pb->size - 8;
 	pb->pos = 0;
 
-	/* allocate and map pushbuffer memory */
-	pb->mapped = dma_alloc_wc(host1x->dev, pb->size_bytes + 4, &pb->phys,
-				  GFP_KERNEL);
-	if (!pb->mapped)
-		goto fail;
+	if (host1x->domain) {
+		unsigned long shift;
+
+		size = iova_align(&host1x->iova, size);
+
+		pb->mapped = dma_alloc_wc(host1x->dev, size, &pb->phys,
+					  GFP_KERNEL);
+		if (!pb->mapped)
+			return -ENOMEM;
+
+		shift = iova_shift(&host1x->iova);
+		alloc = alloc_iova(&host1x->iova, size >> shift,
+				   host1x->iova_end >> shift, true);
+		if (!alloc) {
+			err = -ENOMEM;
+			goto iommu_free_mem;
+		}
+
+		pb->dma = iova_dma_addr(&host1x->iova, alloc);
+		err = iommu_map(host1x->domain, pb->dma, pb->phys, size,
+				IOMMU_READ);
+		if (err)
+			goto iommu_free_iova;
+	} else {
+		pb->mapped = dma_alloc_wc(host1x->dev, size, &pb->phys,
+					  GFP_KERNEL);
+		if (!pb->mapped)
+			return -ENOMEM;
+
+		pb->dma = pb->phys;
+	}
+
+	pb->alloc_size = size;
 
 	host1x_hw_pushbuffer_init(host1x, pb);
 
 	return 0;
 
-fail:
-	host1x_pushbuffer_destroy(pb);
-	return -ENOMEM;
+iommu_free_iova:
+	__free_iova(&host1x->iova, alloc);
+iommu_free_mem:
+	dma_free_wc(host1x->dev, pb->alloc_size, pb->mapped, pb->phys);
+
+	return err;
 }
 
 /*
@@ -101,7 +143,7 @@ static void host1x_pushbuffer_push(struct push_buffer *pb, u32 op1, u32 op2)
 	WARN_ON(pb->pos == pb->fence);
 	*(p++) = op1;
 	*(p++) = op2;
-	pb->pos = (pb->pos + 8) & (pb->size_bytes - 1);
+	pb->pos = (pb->pos + 8) & (pb->size - 1);
 }
 
 /*
@@ -111,7 +153,7 @@ static void host1x_pushbuffer_push(struct push_buffer *pb, u32 op1, u32 op2)
 static void host1x_pushbuffer_pop(struct push_buffer *pb, unsigned int slots)
 {
 	/* Advance the next write position */
-	pb->fence = (pb->fence + slots * 8) & (pb->size_bytes - 1);
+	pb->fence = (pb->fence + slots * 8) & (pb->size - 1);
 }
 
 /*
@@ -119,7 +161,7 @@ static void host1x_pushbuffer_pop(struct push_buffer *pb, unsigned int slots)
  */
 static u32 host1x_pushbuffer_space(struct push_buffer *pb)
 {
-	return ((pb->fence - pb->pos) & (pb->size_bytes - 1)) / 8;
+	return ((pb->fence - pb->pos) & (pb->size - 1)) / 8;
 }
 
 /*
diff --git a/drivers/gpu/host1x/cdma.h b/drivers/gpu/host1x/cdma.h
index 470087af8fe5..ec170a78f4e1 100644
--- a/drivers/gpu/host1x/cdma.h
+++ b/drivers/gpu/host1x/cdma.h
@@ -43,10 +43,12 @@ struct host1x_job;
 
 struct push_buffer {
 	void *mapped;			/* mapped pushbuffer memory */
-	dma_addr_t phys;		/* physical address of pushbuffer */
+	dma_addr_t dma;			/* device address of pushbuffer */
+	phys_addr_t phys;		/* physical address of pushbuffer */
 	u32 fence;			/* index we've written */
 	u32 pos;			/* index to write to */
-	u32 size_bytes;
+	u32 size;
+	u32 alloc_size;
 };
 
 struct buffer_timeout {
diff --git a/drivers/gpu/host1x/dev.c b/drivers/gpu/host1x/dev.c
index a62317af76ad..f05ebb14fa63 100644
--- a/drivers/gpu/host1x/dev.c
+++ b/drivers/gpu/host1x/dev.c
@@ -16,23 +16,25 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <linux/module.h>
-#include <linux/list.h>
-#include <linux/slab.h>
-#include <linux/of.h>
-#include <linux/of_device.h>
 #include <linux/clk.h>
-#include <linux/io.h>
 #include <linux/dma-mapping.h>
+#include <linux/io.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/of.h>
+#include <linux/slab.h>
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/host1x.h>
+#undef CREATE_TRACE_POINTS
 
 #include "bus.h"
-#include "dev.h"
-#include "intr.h"
 #include "channel.h"
 #include "debug.h"
+#include "dev.h"
+#include "intr.h"
+
 #include "hw/host1x01.h"
 #include "hw/host1x02.h"
 #include "hw/host1x04.h"
@@ -168,22 +170,56 @@ static int host1x_probe(struct platform_device *pdev)
 		return err;
 	}
 
+	host->rst = devm_reset_control_get(&pdev->dev, "host1x");
+	if (IS_ERR(host->rst)) {
+		err = PTR_ERR(host->clk);
+		dev_err(&pdev->dev, "failed to get reset: %d\n", err);
+		return err;
+	}
+
+	if (iommu_present(&platform_bus_type)) {
+		struct iommu_domain_geometry *geometry;
+		unsigned long order;
+
+		host->domain = iommu_domain_alloc(&platform_bus_type);
+		if (!host->domain)
+			return -ENOMEM;
+
+		err = iommu_attach_device(host->domain, &pdev->dev);
+		if (err)
+			goto fail_free_domain;
+
+		geometry = &host->domain->geometry;
+
+		order = __ffs(host->domain->pgsize_bitmap);
+		init_iova_domain(&host->iova, 1UL << order,
+				 geometry->aperture_start >> order,
+				 geometry->aperture_end >> order);
+		host->iova_end = geometry->aperture_end;
+	}
+
 	err = host1x_channel_list_init(host);
 	if (err) {
 		dev_err(&pdev->dev, "failed to initialize channel list\n");
-		return err;
+		goto fail_detach_device;
 	}
 
 	err = clk_prepare_enable(host->clk);
 	if (err < 0) {
 		dev_err(&pdev->dev, "failed to enable clock\n");
-		return err;
+		goto fail_detach_device;
+	}
+
+	err = reset_control_deassert(host->rst);
+	if (err < 0) {
+		dev_err(&pdev->dev, "failed to deassert reset: %d\n", err);
+		goto fail_unprepare_disable;
 	}
 
 	err = host1x_syncpt_init(host);
 	if (err) {
 		dev_err(&pdev->dev, "failed to initialize syncpts\n");
-		goto fail_unprepare_disable;
+		goto fail_reset_assert;
 	}
 
 	err = host1x_intr_init(host, syncpt_irq);
@@ -204,8 +240,19 @@ fail_deinit_intr:
 	host1x_intr_deinit(host);
 fail_deinit_syncpt:
 	host1x_syncpt_deinit(host);
+fail_reset_assert:
+	reset_control_assert(host->rst);
 fail_unprepare_disable:
 	clk_disable_unprepare(host->clk);
+fail_detach_device:
+	if (host->domain) {
+		put_iova_domain(&host->iova);
+		iommu_detach_device(host->domain, &pdev->dev);
+	}
+fail_free_domain:
+	if (host->domain)
+		iommu_domain_free(host->domain);
+
 	return err;
 }
 
@@ -216,8 +263,15 @@ static int host1x_remove(struct platform_device *pdev)
 	host1x_unregister(host);
 	host1x_intr_deinit(host);
 	host1x_syncpt_deinit(host);
+	reset_control_assert(host->rst);
 	clk_disable_unprepare(host->clk);
 
+	if (host->domain) {
+		put_iova_domain(&host->iova);
+		iommu_detach_device(host->domain, &pdev->dev);
+		iommu_domain_free(host->domain);
+	}
+
 	return 0;
 }
 
diff --git a/drivers/gpu/host1x/dev.h b/drivers/gpu/host1x/dev.h
index 06dd4f85125f..229d08b6a45e 100644
--- a/drivers/gpu/host1x/dev.h
+++ b/drivers/gpu/host1x/dev.h
@@ -17,14 +17,17 @@
 #ifndef HOST1X_DEV_H
 #define HOST1X_DEV_H
 
-#include <linux/platform_device.h>
 #include <linux/device.h>
+#include <linux/iommu.h>
+#include <linux/iova.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
 
+#include "cdma.h"
 #include "channel.h"
-#include "syncpt.h"
 #include "intr.h"
-#include "cdma.h"
 #include "job.h"
+#include "syncpt.h"
 
 struct host1x_syncpt;
 struct host1x_syncpt_base;
@@ -107,6 +110,11 @@ struct host1x {
 	struct host1x_syncpt_base *bases;
 	struct device *dev;
 	struct clk *clk;
+	struct reset_control *rst;
+
+	struct iommu_domain *domain;
+	struct iova_domain iova;
+	dma_addr_t iova_end;
 
 	struct mutex intr_mutex;
 	int intr_syncpt_irq;
diff --git a/drivers/gpu/host1x/hw/cdma_hw.c b/drivers/gpu/host1x/hw/cdma_hw.c
index 659c1bbfeeba..6b231119193e 100644
--- a/drivers/gpu/host1x/hw/cdma_hw.c
+++ b/drivers/gpu/host1x/hw/cdma_hw.c
@@ -30,7 +30,7 @@
  */
 static void push_buffer_init(struct push_buffer *pb)
 {
-	*(u32 *)(pb->mapped + pb->size_bytes) = host1x_opcode_restart(0);
+	*(u32 *)(pb->mapped + pb->size) = host1x_opcode_restart(0);
 }
 
 /*
@@ -55,8 +55,8 @@ static void cdma_timeout_cpu_incr(struct host1x_cdma *cdma, u32 getptr,
 		*(p++) = HOST1X_OPCODE_NOP;
 		*(p++) = HOST1X_OPCODE_NOP;
 		dev_dbg(host1x->dev, "%s: NOP at %pad+%#x\n", __func__,
-			&pb->phys, getptr);
-		getptr = (getptr + 8) & (pb->size_bytes - 1);
+			&pb->dma, getptr);
+		getptr = (getptr + 8) & (pb->size - 1);
 	}
 
 	wmb();
@@ -78,10 +78,9 @@ static void cdma_start(struct host1x_cdma *cdma)
 			 HOST1X_CHANNEL_DMACTRL);
 
 	/* set base, put and end pointer */
-	host1x_ch_writel(ch, cdma->push_buffer.phys, HOST1X_CHANNEL_DMASTART);
+	host1x_ch_writel(ch, cdma->push_buffer.dma, HOST1X_CHANNEL_DMASTART);
 	host1x_ch_writel(ch, cdma->push_buffer.pos, HOST1X_CHANNEL_DMAPUT);
-	host1x_ch_writel(ch, cdma->push_buffer.phys +
-			 cdma->push_buffer.size_bytes + 4,
+	host1x_ch_writel(ch, cdma->push_buffer.dma + cdma->push_buffer.size + 4,
 			 HOST1X_CHANNEL_DMAEND);
 
 	/* reset GET */
@@ -115,9 +114,8 @@ static void cdma_timeout_restart(struct host1x_cdma *cdma, u32 getptr)
 			 HOST1X_CHANNEL_DMACTRL);
 
 	/* set base, end pointer (all of memory) */
-	host1x_ch_writel(ch, cdma->push_buffer.phys, HOST1X_CHANNEL_DMASTART);
-	host1x_ch_writel(ch, cdma->push_buffer.phys +
-			 cdma->push_buffer.size_bytes,
+	host1x_ch_writel(ch, cdma->push_buffer.dma, HOST1X_CHANNEL_DMASTART);
+	host1x_ch_writel(ch, cdma->push_buffer.dma + cdma->push_buffer.size,
 			 HOST1X_CHANNEL_DMAEND);
 
 	/* set GET, by loading the value in PUT (then reset GET) */
diff --git a/drivers/gpu/host1x/job.c b/drivers/gpu/host1x/job.c
index 92c3df933303..5f5f8ee6143d 100644
--- a/drivers/gpu/host1x/job.c
+++ b/drivers/gpu/host1x/job.c
@@ -174,9 +174,10 @@ static int do_waitchks(struct host1x_job *job, struct host1x *host,
 	return 0;
 }
 
-static unsigned int pin_job(struct host1x_job *job)
+static unsigned int pin_job(struct host1x *host, struct host1x_job *job)
 {
 	unsigned int i;
+	int err;
 
 	job->num_unpins = 0;
 
@@ -186,12 +187,16 @@ static unsigned int pin_job(struct host1x_job *job)
 		dma_addr_t phys_addr;
 
 		reloc->target.bo = host1x_bo_get(reloc->target.bo);
-		if (!reloc->target.bo)
+		if (!reloc->target.bo) {
+			err = -EINVAL;
 			goto unpin;
+		}
 
 		phys_addr = host1x_bo_pin(reloc->target.bo, &sgt);
-		if (!phys_addr)
+		if (!phys_addr) {
+			err = -EINVAL;
 			goto unpin;
+		}
 
 		job->addr_phys[job->num_unpins] = phys_addr;
 		job->unpins[job->num_unpins].bo = reloc->target.bo;
@@ -201,28 +206,67 @@ static unsigned int pin_job(struct host1x_job *job)
 
 	for (i = 0; i < job->num_gathers; i++) {
 		struct host1x_job_gather *g = &job->gathers[i];
+		size_t gather_size = 0;
+		struct scatterlist *sg;
 		struct sg_table *sgt;
 		dma_addr_t phys_addr;
+		unsigned long shift;
+		struct iova *alloc;
+		unsigned int j;
 
 		g->bo = host1x_bo_get(g->bo);
-		if (!g->bo)
+		if (!g->bo) {
+			err = -EINVAL;
 			goto unpin;
+		}
 
 		phys_addr = host1x_bo_pin(g->bo, &sgt);
-		if (!phys_addr)
+		if (!phys_addr) {
+			err = -EINVAL;
 			goto unpin;
+		}
+
+		if (!IS_ENABLED(CONFIG_TEGRA_HOST1X_FIREWALL) && host->domain) {
+			for_each_sg(sgt->sgl, sg, sgt->nents, j)
+				gather_size += sg->length;
+			gather_size = iova_align(&host->iova, gather_size);
+
+			shift = iova_shift(&host->iova);
+			alloc = alloc_iova(&host->iova, gather_size >> shift,
+					   host->iova_end >> shift, true);
+			if (!alloc) {
+				err = -ENOMEM;
+				goto unpin;
+			}
+
+			err = iommu_map_sg(host->domain,
+					iova_dma_addr(&host->iova, alloc),
+					sgt->sgl, sgt->nents, IOMMU_READ);
+			if (err == 0) {
+				__free_iova(&host->iova, alloc);
+				err = -EINVAL;
+				goto unpin;
+			}
+
+			job->addr_phys[job->num_unpins] =
+				iova_dma_addr(&host->iova, alloc);
+			job->unpins[job->num_unpins].size = gather_size;
+		} else {
+			job->addr_phys[job->num_unpins] = phys_addr;
+		}
+
+		job->gather_addr_phys[i] = job->addr_phys[job->num_unpins];
 
-		job->addr_phys[job->num_unpins] = phys_addr;
 		job->unpins[job->num_unpins].bo = g->bo;
 		job->unpins[job->num_unpins].sgt = sgt;
 		job->num_unpins++;
 	}
 
-	return job->num_unpins;
+	return 0;
 
 unpin:
 	host1x_job_unpin(job);
-	return 0;
+	return err;
 }
 
 static int do_relocs(struct host1x_job *job, struct host1x_bo *cmdbuf)
@@ -525,8 +569,8 @@ int host1x_job_pin(struct host1x_job *job, struct device *dev)
 		host1x_syncpt_load(host->syncpt + i);
 
 	/* pin memory */
-	err = pin_job(job);
-	if (!err)
+	err = pin_job(host, job);
+	if (err)
 		goto out;
 
 	/* patch gathers */
@@ -572,11 +616,19 @@ EXPORT_SYMBOL(host1x_job_pin);
 
 void host1x_job_unpin(struct host1x_job *job)
 {
+	struct host1x *host = dev_get_drvdata(job->channel->dev->parent);
 	unsigned int i;
 
 	for (i = 0; i < job->num_unpins; i++) {
 		struct host1x_job_unpin_data *unpin = &job->unpins[i];
 
+		if (!IS_ENABLED(CONFIG_TEGRA_HOST1X_FIREWALL) && host->domain) {
+			iommu_unmap(host->domain, job->addr_phys[i],
+				    unpin->size);
+			free_iova(&host->iova,
+				iova_pfn(&host->iova, job->addr_phys[i]));
+		}
+
 		host1x_bo_unpin(unpin->bo, unpin->sgt);
 		host1x_bo_put(unpin->bo);
 	}
diff --git a/drivers/gpu/host1x/job.h b/drivers/gpu/host1x/job.h
index 8b3c15df0660..878239c476d2 100644
--- a/drivers/gpu/host1x/job.h
+++ b/drivers/gpu/host1x/job.h
@@ -44,6 +44,7 @@ struct host1x_waitchk {
 struct host1x_job_unpin_data {
 	struct host1x_bo *bo;
 	struct sg_table *sgt;
+	size_t size;
 };
 
 /*
diff --git a/drivers/gpu/host1x/syncpt.c b/drivers/gpu/host1x/syncpt.c
index 25c11a85050b..0ac026cdc30c 100644
--- a/drivers/gpu/host1x/syncpt.c
+++ b/drivers/gpu/host1x/syncpt.c
@@ -484,7 +484,7 @@ unsigned int host1x_syncpt_nb_mlocks(struct host1x *host)
 
 struct host1x_syncpt *host1x_syncpt_get(struct host1x *host, unsigned int id)
 {
-	if (host->info->nb_pts < id)
+	if (id >= host->info->nb_pts)
 		return NULL;
 
 	return host->syncpt + id;