1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright(c) 2020 Intel Corporation.
4  */
5 #include <linux/workqueue.h>
6 #include "intel_pxp.h"
7 #include "intel_pxp_irq.h"
8 #include "intel_pxp_session.h"
9 #include "gt/intel_gt_irq.h"
10 #include "gt/intel_gt_regs.h"
11 #include "gt/intel_gt_types.h"
12 #include "i915_irq.h"
13 #include "i915_reg.h"
14 #include "intel_runtime_pm.h"
15 
16 /**
17  * intel_pxp_irq_handler - Handles PXP interrupts.
18  * @pxp: pointer to pxp struct
19  * @iir: interrupt vector
20  */
21 void intel_pxp_irq_handler(struct intel_pxp *pxp, u16 iir)
22 {
23 	struct intel_gt *gt = pxp_to_gt(pxp);
24 
25 	if (GEM_WARN_ON(!intel_pxp_is_enabled(pxp)))
26 		return;
27 
28 	lockdep_assert_held(&gt->irq_lock);
29 
30 	if (unlikely(!iir))
31 		return;
32 
33 	if (iir & (GEN12_DISPLAY_PXP_STATE_TERMINATED_INTERRUPT |
34 		   GEN12_DISPLAY_APP_TERMINATED_PER_FW_REQ_INTERRUPT)) {
35 		/* immediately mark PXP as inactive on termination */
36 		intel_pxp_mark_termination_in_progress(pxp);
37 		pxp->session_events |= PXP_TERMINATION_REQUEST | PXP_INVAL_REQUIRED;
38 	}
39 
40 	if (iir & GEN12_DISPLAY_STATE_RESET_COMPLETE_INTERRUPT)
41 		pxp->session_events |= PXP_TERMINATION_COMPLETE;
42 
43 	if (pxp->session_events)
44 		queue_work(system_unbound_wq, &pxp->session_work);
45 }
46 
47 static inline void __pxp_set_interrupts(struct intel_gt *gt, u32 interrupts)
48 {
49 	struct intel_uncore *uncore = gt->uncore;
50 	const u32 mask = interrupts << 16;
51 
52 	intel_uncore_write(uncore, GEN11_CRYPTO_RSVD_INTR_ENABLE, mask);
53 	intel_uncore_write(uncore, GEN11_CRYPTO_RSVD_INTR_MASK,  ~mask);
54 }
55 
56 static inline void pxp_irq_reset(struct intel_gt *gt)
57 {
58 	spin_lock_irq(&gt->irq_lock);
59 	gen11_gt_reset_one_iir(gt, 0, GEN11_KCR);
60 	spin_unlock_irq(&gt->irq_lock);
61 }
62 
63 void intel_pxp_irq_enable(struct intel_pxp *pxp)
64 {
65 	struct intel_gt *gt = pxp_to_gt(pxp);
66 
67 	spin_lock_irq(&gt->irq_lock);
68 
69 	if (!pxp->irq_enabled)
70 		WARN_ON_ONCE(gen11_gt_reset_one_iir(gt, 0, GEN11_KCR));
71 
72 	__pxp_set_interrupts(gt, GEN12_PXP_INTERRUPTS);
73 	pxp->irq_enabled = true;
74 
75 	spin_unlock_irq(&gt->irq_lock);
76 }
77 
78 void intel_pxp_irq_disable(struct intel_pxp *pxp)
79 {
80 	struct intel_gt *gt = pxp_to_gt(pxp);
81 
82 	/*
83 	 * We always need to submit a global termination when we re-enable the
84 	 * interrupts, so there is no need to make sure that the session state
85 	 * makes sense at the end of this function. Just make sure this is not
86 	 * called in a path were the driver consider the session as valid and
87 	 * doesn't call a termination on restart.
88 	 */
89 	GEM_WARN_ON(intel_pxp_is_active(pxp));
90 
91 	spin_lock_irq(&gt->irq_lock);
92 
93 	pxp->irq_enabled = false;
94 	__pxp_set_interrupts(gt, 0);
95 
96 	spin_unlock_irq(&gt->irq_lock);
97 	intel_synchronize_irq(gt->i915);
98 
99 	pxp_irq_reset(gt);
100 
101 	flush_work(&pxp->session_work);
102 }
103