Re: [Intel-gfx] [PATCH v11 08/17] drm/i915/pxp: Implement arb session teardown

Harish Chegondi
2021-09-22T22:56:09Z

On Tue, Sep 21, 2021 at 05:15:22PM -0700, Alan Previn wrote:
> From: "Huang, Sean Z" <sean.z.huang@intel.com>
>
> Teardown is triggered when the display topology changes and no
> long meets the secure playback requirement, and hardware trashes
> all the encryption keys for display. Additionally, we want to emit a
> teardown operation to make sure we're clean on boot and resume
>
> v2: emit in the ring, use high prio request (Chris)
> v3: better defines, stalling flush, cleaned up and renamed submission
> funcs (Chris)
>
> Signed-off-by: Huang, Sean Z <sean.z.huang@intel.com>
> Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
> Cc: Chris Wilson <chris@chris-wilson.co.uk>
> Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
> ---
> drivers/gpu/drm/i915/Makefile | 1 +
> drivers/gpu/drm/i915/gt/intel_gpu_commands.h | 22 ++-
> drivers/gpu/drm/i915/pxp/intel_pxp.c | 7 +-
> drivers/gpu/drm/i915/pxp/intel_pxp_cmd.c | 141 +++++++++++++++++++
> drivers/gpu/drm/i915/pxp/intel_pxp_cmd.h | 15 ++
> drivers/gpu/drm/i915/pxp/intel_pxp_session.c | 29 ++++
> drivers/gpu/drm/i915/pxp/intel_pxp_session.h | 1 +
> 7 files changed, 212 insertions(+), 4 deletions(-)
> create mode 100644 drivers/gpu/drm/i915/pxp/intel_pxp_cmd.c
> create mode 100644 drivers/gpu/drm/i915/pxp/intel_pxp_cmd.h
>
> diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
> index 334efd835cd8..ac4585f98e43 100644
> --- a/drivers/gpu/drm/i915/Makefile
> +++ b/drivers/gpu/drm/i915/Makefile
> @@ -283,6 +283,7 @@ i915-y += i915_perf.o
> # Protected execution platform (PXP) support
> i915-$(CONFIG_DRM_I915_PXP) += \
> pxp/intel_pxp.o \
> + pxp/intel_pxp_cmd.o \
> pxp/intel_pxp_session.o \
> pxp/intel_pxp_tee.o
>
> diff --git a/drivers/gpu/drm/i915/gt/intel_gpu_commands.h b/drivers/gpu/drm/i915/gt/intel_gpu_commands.h
> index 1c3af0fc0456..f8253012d166 100644
> --- a/drivers/gpu/drm/i915/gt/intel_gpu_commands.h
> +++ b/drivers/gpu/drm/i915/gt/intel_gpu_commands.h
> @@ -28,10 +28,13 @@
> #define INSTR_26_TO_24_MASK 0x7000000
> #define INSTR_26_TO_24_SHIFT 24
>
> +#define __INSTR(client) ((client) << INSTR_CLIENT_SHIFT)
> +
> /*
> * Memory interface instructions used by the kernel
> */
> -#define MI_INSTR(opcode, flags) (((opcode) << 23) | (flags))
> +#define MI_INSTR(opcode, flags) \
> + (__INSTR(INSTR_MI_CLIENT) | (opcode) << 23 | (flags))
> /* Many MI commands use bit 22 of the header dword for GGTT vs PPGTT */
> #define MI_GLOBAL_GTT (1<<22)
>
> @@ -57,6 +60,7 @@
> #define MI_SUSPEND_FLUSH MI_INSTR(0x0b, 0)
> #define MI_SUSPEND_FLUSH_EN (1<<0)
> #define MI_SET_APPID MI_INSTR(0x0e, 0)
> +#define MI_SET_APPID_SESSION_ID(x) ((x) << 0)
> #define MI_OVERLAY_FLIP MI_INSTR(0x11, 0)
> #define MI_OVERLAY_CONTINUE (0x0<<21)
> #define MI_OVERLAY_ON (0x1<<21)
> @@ -146,6 +150,7 @@
> #define MI_STORE_REGISTER_MEM_GEN8 MI_INSTR(0x24, 2)
> #define MI_SRM_LRM_GLOBAL_GTT (1<<22)
> #define MI_FLUSH_DW MI_INSTR(0x26, 1) /* for GEN6 */
> +#define MI_FLUSH_DW_PROTECTED_MEM_EN (1 << 22)
> #define MI_FLUSH_DW_STORE_INDEX (1<<21)
> #define MI_INVALIDATE_TLB (1<<18)
> #define MI_FLUSH_DW_OP_STOREDW (1<<14)
> @@ -272,6 +277,19 @@
> #define MI_MATH_REG_ZF 0x32
> #define MI_MATH_REG_CF 0x33
>
> +/*
> + * Media instructions used by the kernel
> + */
> +#define MEDIA_INSTR(pipe, op, sub_op, flags) \
> + (__INSTR(INSTR_RC_CLIENT) | (pipe) << INSTR_SUBCLIENT_SHIFT | \
> + (op) << INSTR_26_TO_24_SHIFT | (sub_op) << 16 | (flags))
> +
> +#define MFX_WAIT MEDIA_INSTR(1, 0, 0, 0)
> +#define MFX_WAIT_DW0_MFX_SYNC_CONTROL_FLAG REG_BIT(8)
> +#define MFX_WAIT_DW0_PXP_SYNC_CONTROL_FLAG REG_BIT(9)
> +
> +#define CRYPTO_KEY_EXCHANGE MEDIA_INSTR(2, 6, 9, 0)
> +
> /*
> * Commands used only by the command parser
> */
> @@ -328,8 +346,6 @@
> #define GFX_OP_3DSTATE_BINDING_TABLE_EDIT_PS \
> ((0x3<<29)|(0x3<<27)|(0x0<<24)|(0x47<<16))
>
> -#define MFX_WAIT ((0x3<<29)|(0x1<<27)|(0x0<<16))
> -
> #define COLOR_BLT ((0x2<<29)|(0x40<<22))
> #define SRC_COPY_BLT ((0x2<<29)|(0x43<<22))
>
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp.c b/drivers/gpu/drm/i915/pxp/intel_pxp.c
> index 54ad5e3d0df2..a589d40e08a8 100644
> --- a/drivers/gpu/drm/i915/pxp/intel_pxp.c
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp.c
> @@ -109,9 +109,14 @@ void intel_pxp_fini(struct intel_pxp *pxp)
>
> void intel_pxp_init_hw(struct intel_pxp *pxp)
> {
> + int ret;
> +
> kcr_pxp_enable(pxp_to_gt(pxp));
>
> - intel_pxp_create_arb_session(pxp);
> + /* always emit a full termination to clean the state */
> + ret = intel_pxp_terminate_arb_session_and_global(pxp);
> + if (!ret)
> + intel_pxp_create_arb_session(pxp);
> }
>
> void intel_pxp_fini_hw(struct intel_pxp *pxp)
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_cmd.c b/drivers/gpu/drm/i915/pxp/intel_pxp_cmd.c
> new file mode 100644
> index 000000000000..80678dafde15
> --- /dev/null
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_cmd.c
> @@ -0,0 +1,141 @@
> +// SPDX-License-Identifier: MIT
> +/*
> + * Copyright(c) 2020, Intel Corporation. All rights reserved.
> + */
> +
> +#include "intel_pxp.h"
> +#include "intel_pxp_cmd.h"
> +#include "intel_pxp_session.h"
> +#include "gt/intel_context.h"
> +#include "gt/intel_engine_pm.h"
> +#include "gt/intel_gpu_commands.h"
> +#include "gt/intel_ring.h"
> +
> +#include "i915_trace.h"
> +
> +/* stall until prior PXP and MFX/HCP/HUC objects are cmopleted */
> +#define MFX_WAIT_PXP (MFX_WAIT | \
> + MFX_WAIT_DW0_PXP_SYNC_CONTROL_FLAG | \
> + MFX_WAIT_DW0_MFX_SYNC_CONTROL_FLAG)
> +
> +static u32 *pxp_emit_session_selection(u32 *cs, u32 idx)
> +{
> + *cs++ = MFX_WAIT_PXP;
> +
> + /* pxp off */
> + *cs++ = MI_FLUSH_DW;
> + *cs++ = 0;
> + *cs++ = 0;
> +
> + /* select session */
> + *cs++ = MI_SET_APPID | MI_SET_APPID_SESSION_ID(idx);
> +
> + *cs++ = MFX_WAIT_PXP;
> +
> + /* pxp on */
> + *cs++ = MI_FLUSH_DW | MI_FLUSH_DW_PROTECTED_MEM_EN |
> + MI_FLUSH_DW_OP_STOREDW | MI_FLUSH_DW_STORE_INDEX;
> + *cs++ = I915_GEM_HWS_PXP_ADDR | MI_FLUSH_DW_USE_GTT;
> + *cs++ = 0;
> +
> + *cs++ = MFX_WAIT_PXP;
> +
> + return cs;
> +}
> +
> +static u32 *pxp_emit_inline_termination(u32 *cs)
> +{
> + /* session inline termination */
> + *cs++ = CRYPTO_KEY_EXCHANGE;
> + *cs++ = 0;
> +
> + return cs;
> +}
> +
> +static u32 *pxp_emit_session_termination(u32 *cs, u32 idx)
> +{
> + cs = pxp_emit_session_selection(cs, idx);
> + cs = pxp_emit_inline_termination(cs);
> +
> + return cs;
> +}
> +
> +static u32 *pxp_emit_wait(u32 *cs)
> +{
> + /* wait for cmds to go through */
> + *cs++ = MFX_WAIT_PXP;
> + *cs++ = 0;
> +
> + return cs;
> +}
> +
> +/*
> + * if we ever need to terminate more than one session, we can submit multiple
> + * selections and terminations back-to-back with a single wait at the end
> + */
> +#define SELECTION_LEN 10
> +#define TERMINATION_LEN 2
> +#define SESSION_TERMINATION_LEN(x) ((SELECTION_LEN + TERMINATION_LEN) * (x))
> +#define WAIT_LEN 2
> +
> +static void pxp_request_commit(struct i915_request *rq)
> +{
> + struct i915_sched_attr attr = { .priority = I915_PRIORITY_MAX };
> + struct intel_timeline * const tl = i915_request_timeline(rq);
> +
> + lockdep_unpin_lock(&tl->mutex, rq->cookie);
> +
> + trace_i915_request_add(rq);
> + __i915_request_commit(rq);
> + __i915_request_queue(rq, &attr);
> +
> + mutex_unlock(&tl->mutex);
> +}
> +
> +int intel_pxp_terminate_session(struct intel_pxp *pxp, u32 id)
> +{
> + struct i915_request *rq;
> + struct intel_context *ce = pxp->ce;
> + u32 *cs;
> + int err;
err needs to be initialized to 0. If not initialized, it may be used
uninitialized in the line I mentioned below.
> +
> + if (!intel_pxp_is_enabled(pxp))
> + return 0;
> +
> + rq = i915_request_create(ce);
> + if (IS_ERR(rq))
> + return PTR_ERR(rq);
> +
> + if (ce->engine->emit_init_breadcrumb) {
> + err = ce->engine->emit_init_breadcrumb(rq);
> + if (err)
> + goto out_rq;
> + }
> +
> + cs = intel_ring_begin(rq, SESSION_TERMINATION_LEN(1) + WAIT_LEN);
> + if (IS_ERR(cs)) {
> + err = PTR_ERR(cs);
> + goto out_rq;
> + }
> +
> + cs = pxp_emit_session_termination(cs, id);
> + cs = pxp_emit_wait(cs);
> +
> + intel_ring_advance(rq, cs);
> +
> +out_rq:
> + i915_request_get(rq);
> +
> + if (unlikely(err))
uninitialized 'err' may be used in the above line.
> + i915_request_set_error_once(rq, err);
> +
> + pxp_request_commit(rq);
> +
> + if (!err && i915_request_wait(rq, 0, HZ / 5) < 0)
> + err = -ETIME;
> +
> + i915_request_put(rq);
> +
> + return err;
> +}
> +
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_cmd.h b/drivers/gpu/drm/i915/pxp/intel_pxp_cmd.h
> new file mode 100644
> index 000000000000..6d6299543578
> --- /dev/null
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_cmd.h
> @@ -0,0 +1,15 @@
> +/* SPDX-License-Identifier: MIT */
> +/*
> + * Copyright(c) 2020, Intel Corporation. All rights reserved.
> + */
> +
> +#ifndef __INTEL_PXP_CMD_H__
> +#define __INTEL_PXP_CMD_H__
> +
> +#include <linux/types.h>
> +
> +struct intel_pxp;
> +
> +int intel_pxp_terminate_session(struct intel_pxp *pxp, u32 idx);
> +
> +#endif /* __INTEL_PXP_CMD_H__ */
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_session.c b/drivers/gpu/drm/i915/pxp/intel_pxp_session.c
> index 3331868f354c..b8e24adeb1f3 100644
> --- a/drivers/gpu/drm/i915/pxp/intel_pxp_session.c
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_session.c
> @@ -7,6 +7,7 @@
> #include "i915_drv.h"
>
> #include "intel_pxp.h"
> +#include "intel_pxp_cmd.h"
> #include "intel_pxp_session.h"
> #include "intel_pxp_tee.h"
> #include "intel_pxp_types.h"
> @@ -15,6 +16,9 @@
>
> #define GEN12_KCR_SIP _MMIO(0x32260) /* KCR hwdrm session in play 0-31 */
>
> +/* PXP global terminate register for session termination */
> +#define PXP_GLOBAL_TERMINATE _MMIO(0x320f8)
> +
> static bool intel_pxp_session_is_in_play(struct intel_pxp *pxp, u32 id)
> {
> struct intel_gt *gt = pxp_to_gt(pxp);
> @@ -72,3 +76,28 @@ int intel_pxp_create_arb_session(struct intel_pxp *pxp)
>
> return 0;
> }
> +
> +int intel_pxp_terminate_arb_session_and_global(struct intel_pxp *pxp)
> +{
> + int ret;
> + struct intel_gt *gt = pxp_to_gt(pxp);
> +
> + pxp->arb_is_valid = false;
> +
> + /* terminate the hw sessions */
> + ret = intel_pxp_terminate_session(pxp, ARB_SESSION);
> + if (ret) {
> + drm_err(&gt->i915->drm, "Failed to submit session termination\n");
> + return ret;
> + }
> +
> + ret = pxp_wait_for_session_state(pxp, ARB_SESSION, false);
> + if (ret) {
> + drm_err(&gt->i915->drm, "Session state did not clear\n");
> + return ret;
> + }
> +
> + intel_uncore_write(gt->uncore, PXP_GLOBAL_TERMINATE, 1);
> +
> + return ret;
> +}
> diff --git a/drivers/gpu/drm/i915/pxp/intel_pxp_session.h b/drivers/gpu/drm/i915/pxp/intel_pxp_session.h
> index 316c3bebed9c..7354314b1cc4 100644
> --- a/drivers/gpu/drm/i915/pxp/intel_pxp_session.h
> +++ b/drivers/gpu/drm/i915/pxp/intel_pxp_session.h
> @@ -11,5 +11,6 @@
> struct intel_pxp;
>
> int intel_pxp_create_arb_session(struct intel_pxp *pxp);
> +int intel_pxp_terminate_arb_session_and_global(struct intel_pxp *pxp);
>
> #endif /* __INTEL_PXP_SESSION_H__ */
> --
> 2.25.1
>