[PATCH 5/8] gpu: host1x: Add IOMMU support
Mikko Perttunen
cyndis at kapsi.fi
Wed Dec 14 08:50:56 UTC 2016
On 05.12.2016 21:49, Thierry Reding wrote:
> 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.
Made a local "size" variable and stored the aperture end and did some
other cleanup as well.
>
>> + 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.
Cleaned up.
>
>> + 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"?
Renamed. Also renamed size_bytes to size for consistency.
>
>> };
>>
>> 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.
Fixed.
>
>>
>> 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.
Fixed.
>
>> +
>> 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.
Fixed.
>
>> + 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.
Fixed.
>
> Thierry
>
Thanks,
Mikko.
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