[PATCH 5/8] gpu: host1x: Add IOMMU support
Thierry Reding
thierry.reding at gmail.com
Mon Dec 5 19:49:24 UTC 2016
On Thu, Nov 10, 2016 at 08:23:42PM +0200, Mikko Perttunen wrote:
> Add support for the Host1x unit to be located behind
> an IOMMU. This is required when gather buffers may be
> allocated non-contiguously in physical memory, as can
> be the case when TegraDRM is also using the IOMMU.
>
> Signed-off-by: Mikko Perttunen <mperttunen at nvidia.com>
> ---
> drivers/gpu/host1x/cdma.c | 65 +++++++++++++++++++++++++++++------
> drivers/gpu/host1x/cdma.h | 4 ++-
> drivers/gpu/host1x/dev.c | 39 +++++++++++++++++++--
> drivers/gpu/host1x/dev.h | 5 +++
> drivers/gpu/host1x/hw/cdma_hw.c | 10 +++---
> drivers/gpu/host1x/job.c | 76 +++++++++++++++++++++++++++++++++++------
> drivers/gpu/host1x/job.h | 1 +
> 7 files changed, 171 insertions(+), 29 deletions(-)
>
> diff --git a/drivers/gpu/host1x/cdma.c b/drivers/gpu/host1x/cdma.c
> index c5d82a8..14692446e 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_bytes);
> + free_iova(&host1x->iova, iova_pfn(&host1x->iova, pb->dma));
> + }
> +
> + dma_free_wc(host1x->dev, pb->alloc_size_bytes, pb->mapped, pb->phys);
>
> pb->mapped = NULL;
> pb->phys = 0;
> @@ -66,28 +72,65 @@ 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;
> + int err;
>
> pb->mapped = NULL;
> pb->phys = 0;
> pb->size_bytes = HOST1X_PUSHBUFFER_SLOTS * 8;
> + pb->alloc_size_bytes = pb->size_bytes + 4;
>
> /* initialize buffer pointers */
> pb->fence = pb->size_bytes - 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;
> +
> + pb->alloc_size_bytes = iova_align(&host1x->iova,
> + pb->alloc_size_bytes);
> +
> + pb->mapped = dma_alloc_wc(host1x->dev, pb->alloc_size_bytes,
> + &pb->phys, GFP_KERNEL);
> + if (!pb->mapped)
> + return -ENOMEM;
> +
> + shift = iova_shift(&host1x->iova);
> + alloc = alloc_iova(
> + &host1x->iova, pb->alloc_size_bytes >> shift,
> + host1x->domain->geometry.aperture_end >> shift, true);
Let's precompute some of these values to make this expression more
compact. For example pb->alloc_size_bytes is used a couple of times, so
it could be stored temporarily in a local variable with a nice and short
name such as "size".
If you store the aperture end, or limit_pfn, as I commented in an
earlier patch, then this also becomes much more compact.
> + if (!alloc) {
> + err = -ENOMEM;
> + goto iommu_free_mem;
> + }
> +
> + err = iommu_map(host1x->domain,
> + iova_dma_addr(&host1x->iova, alloc),
> + pb->phys, pb->alloc_size_bytes,
> + IOMMU_READ);
Same here.
> + if (err)
> + goto iommu_free_iova;
> +
> + pb->dma = iova_dma_addr(&host1x->iova, alloc);
> + } else {
> + pb->mapped = dma_alloc_wc(host1x->dev, pb->alloc_size_bytes,
> + &pb->phys, GFP_KERNEL);
> + if (!pb->mapped)
> + return -ENOMEM;
> +
> + pb->dma = pb->phys;
> + }
>
> 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_bytes, pb->mapped, pb->phys);
> +
> + return err;
> }
>
> /*
> diff --git a/drivers/gpu/host1x/cdma.h b/drivers/gpu/host1x/cdma.h
> index 470087a..4b3645f 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 alloc_size_bytes;
Maybe just "alloc_size"?
> };
>
> struct buffer_timeout {
> diff --git a/drivers/gpu/host1x/dev.c b/drivers/gpu/host1x/dev.c
> index a62317a..ca4527e 100644
> --- a/drivers/gpu/host1x/dev.c
> +++ b/drivers/gpu/host1x/dev.c
> @@ -168,16 +168,36 @@ static int host1x_probe(struct platform_device *pdev)
> 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);
> + }
> +
> 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 = host1x_syncpt_init(host);
> @@ -206,6 +226,15 @@ static int host1x_probe(struct platform_device *pdev)
> host1x_syncpt_deinit(host);
> 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;
> }
>
> @@ -218,6 +247,12 @@ static int host1x_remove(struct platform_device *pdev)
> host1x_syncpt_deinit(host);
> 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 5220510..6189825 100644
> --- a/drivers/gpu/host1x/dev.h
> +++ b/drivers/gpu/host1x/dev.h
> @@ -19,6 +19,8 @@
>
> #include <linux/platform_device.h>
> #include <linux/device.h>
> +#include <linux/iommu.h>
> +#include <linux/iova.h>
>
> #include "channel.h"
> #include "syncpt.h"
> @@ -108,6 +110,9 @@ struct host1x {
> struct device *dev;
> struct clk *clk;
>
> + struct iommu_domain *domain;
> + struct iova_domain iova;
> +
> 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 659c1bb..b8c0348 100644
> --- a/drivers/gpu/host1x/hw/cdma_hw.c
> +++ b/drivers/gpu/host1x/hw/cdma_hw.c
> @@ -55,7 +55,7 @@ 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);
> + &pb->dma, getptr);
> getptr = (getptr + 8) & (pb->size_bytes - 1);
> }
>
> @@ -78,9 +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 +
> + host1x_ch_writel(ch, cdma->push_buffer.dma +
> cdma->push_buffer.size_bytes + 4,
> HOST1X_CHANNEL_DMAEND);
>
> @@ -115,8 +115,8 @@ 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 +
> + host1x_ch_writel(ch, cdma->push_buffer.dma, HOST1X_CHANNEL_DMASTART);
> + host1x_ch_writel(ch, cdma->push_buffer.dma +
> cdma->push_buffer.size_bytes,
> HOST1X_CHANNEL_DMAEND);
>
> diff --git a/drivers/gpu/host1x/job.c b/drivers/gpu/host1x/job.c
> index a91b7c4..222d930 100644
> --- a/drivers/gpu/host1x/job.c
> +++ b/drivers/gpu/host1x/job.c
> @@ -174,8 +174,9 @@ 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)
> {
> + int err;
> unsigned int i;
Maybe use an inverse christmas tree for variables as in other parts of
this driver? That is, add the new int err belowe the existing unsined
int i.
>
> 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;
> @@ -204,25 +209,68 @@ static unsigned int pin_job(struct host1x_job *job)
> struct sg_table *sgt;
> dma_addr_t phys_addr;
>
> + size_t gather_size = 0;
> + struct scatterlist *sg;
> + struct iova *alloc;
> + unsigned long shift;
> + int j;
There should be no blank line between blocks of variable declarations.
Also, make j an unsigned int.
> +
> 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;
> + }
No need for curly brackets here.
> + gather_size = iova_align(&host->iova, gather_size);
> +
> + shift = iova_shift(&host->iova);
> + alloc = alloc_iova(
> + &host->iova, gather_size >> shift,
> + host->domain->geometry.aperture_end >> shift,
> + true);
This could be made a little more compact as well.
Thierry
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