On Thu, Aug 13, 2020 at 07:41:00PM -0700, Rob Clark wrote: > From: Rob Clark <robdcl...@chromium.org> > > This interface will be used for drm/msm to coordinate with the > qcom_adreno_smmu_impl to enable/disable TTBR0 translation. > > Once TTBR0 translation is enabled, the GPU's CP (Command Processor) > will directly switch TTBR0 pgtables (and do the necessary TLB inv) > synchronized to the GPU's operation. But help from the SMMU driver > is needed to initially bootstrap TTBR0 translation, which cannot be > done from the GPU. > > Since this is a very special case, a private interface is used to > avoid adding highly driver specific things to the public iommu > interface. >
Reviewed-by: Jordan Crouse <jcro...@codeaurora.org> > Signed-off-by: Rob Clark <robdcl...@chromium.org> > --- > include/linux/adreno-smmu-priv.h | 36 ++++++++++++++++++++++++++++++++ > 1 file changed, 36 insertions(+) > create mode 100644 include/linux/adreno-smmu-priv.h > > diff --git a/include/linux/adreno-smmu-priv.h > b/include/linux/adreno-smmu-priv.h > new file mode 100644 > index 000000000000..a889f28afb42 > --- /dev/null > +++ b/include/linux/adreno-smmu-priv.h > @@ -0,0 +1,36 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (C) 2020 Google, Inc > + */ > + > +#ifndef __ADRENO_SMMU_PRIV_H > +#define __ADRENO_SMMU_PRIV_H > + > +#include <linux/io-pgtable.h> > + > +/** > + * struct adreno_smmu_priv - private interface between adreno-smmu and GPU > + * > + * @cookie: An opque token provided by adreno-smmu and passed > + * back into the callbacks > + * @get_ttbr1_cfg: Get the TTBR1 config for the GPUs context-bank > + * @set_ttbr0_cfg: Set the TTBR0 config for the GPUs context bank. A > + * NULL config disables TTBR0 translation, otherwise > + * TTBR0 translation is enabled with the specified cfg > + * > + * The GPU driver (drm/msm) and adreno-smmu work together for controlling > + * the GPU's SMMU instance. This is by necessity, as the GPU is directly > + * updating the SMMU for context switches, while on the other hand we do > + * not want to duplicate all of the initial setup logic from arm-smmu. > + * > + * This private interface is used for the two drivers to coordinate. The > + * cookie and callback functions are populated when the GPU driver attaches > + * it's domain. > + */ > +struct adreno_smmu_priv { > + const void *cookie; > + const struct io_pgtable_cfg *(*get_ttbr1_cfg)(const void *cookie); > + int (*set_ttbr0_cfg)(const void *cookie, const struct io_pgtable_cfg > *cfg); > +}; > + > +#endif /* __ADRENO_SMMU_PRIV_H */ > \ No newline at end of file > -- > 2.26.2 > > _______________________________________________ > Freedreno mailing list > freedr...@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/freedreno -- The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project