Re: [PATCH] drm/msm: update and activate iommu support

From: Rob Clark
Date: Mon Jun 16 2014 - 16:33:19 EST


On Mon, Jun 16, 2014 at 2:20 PM, Stephane Viau <sviau@xxxxxxxxxxxxxx> wrote:
> This changes activates the iommu support for MDP5, through the
> platform config structure.
>
> Iommu support is also slightly modified in order to make sure
> that MDP iommu is properly cleaned up if a probe deferral is
> requested. Before this change, IOMMU faults would occur if the
> probe failed (-EPROBE_DEFER).

So, this looks like it is really two patches.. one making
-EPROBE_DEFER work properly, and the other adding the missing bits for
mdp5 which so far are only on downstream kernel.

Could you split this patch into two, so I can queue the -EPROBE_DEFER
fix for a 3.16 -fixes pull req?

BR,
-R


> Signed-off-by: Stephane Viau <sviau@xxxxxxxxxxxxxx>
> ---
> drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c | 28 +++++++++++++++++++++++-----
> drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.h | 1 +
> drivers/gpu/drm/msm/msm_gem.c | 6 ++++++
> drivers/gpu/drm/msm/msm_iommu.c | 21 +++++++++++++++++++--
> drivers/gpu/drm/msm/msm_mmu.h | 1 +
> 5 files changed, 50 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c
> index 2967b19..62ee5cd 100644
> --- a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c
> +++ b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.c
> @@ -20,6 +20,10 @@
> #include "msm_mmu.h"
> #include "mdp5_kms.h"
>
> +static const char *iommu_ports[] = {
> + "mdp_0",
> +};
> +
> static struct mdp5_platform_config *mdp5_get_config(struct platform_device *dev);
>
> uint32_t __read_mostly _mdp5_pipe_vig_base;
> @@ -201,6 +205,12 @@ static void mdp5_preclose(struct msm_kms *kms, struct drm_file *file)
> static void mdp5_destroy(struct msm_kms *kms)
> {
> struct mdp5_kms *mdp5_kms = to_mdp5_kms(to_mdp_kms(kms));
> + struct msm_mmu *mmu = mdp5_kms->mmu;
> +
> + if (mmu) {
> + mmu->funcs->detach(mmu, iommu_ports, ARRAY_SIZE(iommu_ports));
> + mmu->funcs->destroy(mmu);
> + }
> kfree(mdp5_kms);
> }
>
> @@ -313,10 +323,6 @@ fail:
> return ret;
> }
>
> -static const char *iommu_ports[] = {
> - "mdp_0",
> -};
> -
> static int get_clk(struct platform_device *pdev, struct clk **clkp,
> const char *name)
> {
> @@ -406,17 +412,23 @@ struct msm_kms *mdp5_kms_init(struct drm_device *dev)
> mmu = msm_iommu_new(dev, config->iommu);
> if (IS_ERR(mmu)) {
> ret = PTR_ERR(mmu);
> + dev_err(dev->dev, "failed to init iommu: %d\n", ret);
> goto fail;
> }
> +
> ret = mmu->funcs->attach(mmu, iommu_ports,
> ARRAY_SIZE(iommu_ports));
> - if (ret)
> + if (ret) {
> + dev_err(dev->dev, "failed to attach iommu: %d\n", ret);
> + mmu->funcs->destroy(mmu);
> goto fail;
> + }
> } else {
> dev_info(dev->dev, "no iommu, fallback to phys "
> "contig buffers for scanout\n");
> mmu = NULL;
> }
> + mdp5_kms->mmu = mmu;
>
> mdp5_kms->id = msm_register_mmu(dev, mmu);
> if (mdp5_kms->id < 0) {
> @@ -445,5 +457,11 @@ static struct mdp5_platform_config *mdp5_get_config(struct platform_device *dev)
> #ifdef CONFIG_OF
> /* TODO */
> #endif
> + config.iommu = iommu_domain_alloc(&platform_bus_type, 0);
> + /* TODO hard-coded in downstream mdss, but should it be? */
> + config.max_clk = 200000000;
> + /* TODO get from DT: */
> + config.smp_blk_cnt = 22;
> +
> return &config;
> }
> diff --git a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.h b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.h
> index 6a89b04..20ea748 100644
> --- a/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.h
> +++ b/drivers/gpu/drm/msm/mdp/mdp5/mdp5_kms.h
> @@ -41,6 +41,7 @@ struct mdp5_kms {
>
> /* mapper-id used to request GEM buffer mapped for scanout: */
> int id;
> + struct msm_mmu *mmu;
>
> /* for tracking smp allocation amongst pipes: */
> mdp5_smp_state_t smp_state;
> diff --git a/drivers/gpu/drm/msm/msm_gem.c b/drivers/gpu/drm/msm/msm_gem.c
> index bb8026d..690d7e7 100644
> --- a/drivers/gpu/drm/msm/msm_gem.c
> +++ b/drivers/gpu/drm/msm/msm_gem.c
> @@ -278,6 +278,7 @@ int msm_gem_get_iova_locked(struct drm_gem_object *obj, int id,
> uint32_t *iova)
> {
> struct msm_gem_object *msm_obj = to_msm_bo(obj);
> + struct drm_device *dev = obj->dev;
> int ret = 0;
>
> if (!msm_obj->domain[id].iova) {
> @@ -285,6 +286,11 @@ int msm_gem_get_iova_locked(struct drm_gem_object *obj, int id,
> struct msm_mmu *mmu = priv->mmus[id];
> struct page **pages = get_pages(obj);
>
> + if (!mmu) {
> + dev_err(dev->dev, "null MMU pointer\n");
> + return -EINVAL;
> + }
> +
> if (IS_ERR(pages))
> return PTR_ERR(pages);
>
> diff --git a/drivers/gpu/drm/msm/msm_iommu.c b/drivers/gpu/drm/msm/msm_iommu.c
> index 92b7459..198b2fe 100644
> --- a/drivers/gpu/drm/msm/msm_iommu.c
> +++ b/drivers/gpu/drm/msm/msm_iommu.c
> @@ -28,7 +28,7 @@ static int msm_fault_handler(struct iommu_domain *iommu, struct device *dev,
> unsigned long iova, int flags, void *arg)
> {
> DBG("*** fault: iova=%08lx, flags=%d", iova, flags);
> - return 0;
> + return -ENOSYS;
> }
>
> static int msm_iommu_attach(struct msm_mmu *mmu, const char **names, int cnt)
> @@ -40,8 +40,10 @@ static int msm_iommu_attach(struct msm_mmu *mmu, const char **names, int cnt)
> for (i = 0; i < cnt; i++) {
> struct device *msm_iommu_get_ctx(const char *ctx_name);
> struct device *ctx = msm_iommu_get_ctx(names[i]);
> - if (IS_ERR_OR_NULL(ctx))
> + if (IS_ERR_OR_NULL(ctx)) {
> + dev_warn(dev->dev, "couldn't get %s context", names[i]);
> continue;
> + }
> ret = iommu_attach_device(iommu->domain, ctx);
> if (ret) {
> dev_warn(dev->dev, "could not attach iommu to %s", names[i]);
> @@ -52,6 +54,20 @@ static int msm_iommu_attach(struct msm_mmu *mmu, const char **names, int cnt)
> return 0;
> }
>
> +static void msm_iommu_detach(struct msm_mmu *mmu, const char **names, int cnt)
> +{
> + struct msm_iommu *iommu = to_msm_iommu(mmu);
> + int i;
> +
> + for (i = 0; i < cnt; i++) {
> + struct device *msm_iommu_get_ctx(const char *ctx_name);
> + struct device *ctx = msm_iommu_get_ctx(names[i]);
> + if (IS_ERR_OR_NULL(ctx))
> + continue;
> + iommu_detach_device(iommu->domain, ctx);
> + }
> +}
> +
> static int msm_iommu_map(struct msm_mmu *mmu, uint32_t iova,
> struct sg_table *sgt, unsigned len, int prot)
> {
> @@ -127,6 +143,7 @@ static void msm_iommu_destroy(struct msm_mmu *mmu)
>
> static const struct msm_mmu_funcs funcs = {
> .attach = msm_iommu_attach,
> + .detach = msm_iommu_detach,
> .map = msm_iommu_map,
> .unmap = msm_iommu_unmap,
> .destroy = msm_iommu_destroy,
> diff --git a/drivers/gpu/drm/msm/msm_mmu.h b/drivers/gpu/drm/msm/msm_mmu.h
> index 0303244..21da6d1 100644
> --- a/drivers/gpu/drm/msm/msm_mmu.h
> +++ b/drivers/gpu/drm/msm/msm_mmu.h
> @@ -22,6 +22,7 @@
>
> struct msm_mmu_funcs {
> int (*attach)(struct msm_mmu *mmu, const char **names, int cnt);
> + void (*detach)(struct msm_mmu *mmu, const char **names, int cnt);
> int (*map)(struct msm_mmu *mmu, uint32_t iova, struct sg_table *sgt,
> unsigned len, int prot);
> int (*unmap)(struct msm_mmu *mmu, uint32_t iova, struct sg_table *sgt,
> --
> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
> hosted by The Linux Foundation
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/