xref: /linux/drivers/gpu/drm/xe/xe_reg_sr.c (revision 7f4f3b14e8079ecde096bd734af10e30d40c27b7)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2022 Intel Corporation
4  */
5 
6 #include "xe_reg_sr.h"
7 
8 #include <kunit/visibility.h>
9 #include <linux/align.h>
10 #include <linux/string_helpers.h>
11 #include <linux/xarray.h>
12 
13 #include <drm/drm_managed.h>
14 #include <drm/drm_print.h>
15 
16 #include "regs/xe_engine_regs.h"
17 #include "regs/xe_gt_regs.h"
18 #include "xe_device.h"
19 #include "xe_device_types.h"
20 #include "xe_force_wake.h"
21 #include "xe_gt.h"
22 #include "xe_gt_mcr.h"
23 #include "xe_gt_printk.h"
24 #include "xe_hw_engine_types.h"
25 #include "xe_macros.h"
26 #include "xe_mmio.h"
27 #include "xe_reg_whitelist.h"
28 #include "xe_rtp_types.h"
29 
30 #define XE_REG_SR_GROW_STEP_DEFAULT	16
31 
32 static void reg_sr_fini(struct drm_device *drm, void *arg)
33 {
34 	struct xe_reg_sr *sr = arg;
35 
36 	xa_destroy(&sr->xa);
37 	kfree(sr->pool.arr);
38 	memset(&sr->pool, 0, sizeof(sr->pool));
39 }
40 
41 int xe_reg_sr_init(struct xe_reg_sr *sr, const char *name, struct xe_device *xe)
42 {
43 	xa_init(&sr->xa);
44 	memset(&sr->pool, 0, sizeof(sr->pool));
45 	sr->pool.grow_step = XE_REG_SR_GROW_STEP_DEFAULT;
46 	sr->name = name;
47 
48 	return drmm_add_action_or_reset(&xe->drm, reg_sr_fini, sr);
49 }
50 EXPORT_SYMBOL_IF_KUNIT(xe_reg_sr_init);
51 
52 static struct xe_reg_sr_entry *alloc_entry(struct xe_reg_sr *sr)
53 {
54 	if (sr->pool.used == sr->pool.allocated) {
55 		struct xe_reg_sr_entry *arr;
56 
57 		arr = krealloc_array(sr->pool.arr,
58 				     ALIGN(sr->pool.allocated + 1, sr->pool.grow_step),
59 				     sizeof(*arr), GFP_KERNEL);
60 		if (!arr)
61 			return NULL;
62 
63 		sr->pool.arr = arr;
64 		sr->pool.allocated += sr->pool.grow_step;
65 	}
66 
67 	return &sr->pool.arr[sr->pool.used++];
68 }
69 
70 static bool compatible_entries(const struct xe_reg_sr_entry *e1,
71 			       const struct xe_reg_sr_entry *e2)
72 {
73 	/*
74 	 * Don't allow overwriting values: clr_bits/set_bits should be disjoint
75 	 * when operating in the same register
76 	 */
77 	if (e1->clr_bits & e2->clr_bits || e1->set_bits & e2->set_bits ||
78 	    e1->clr_bits & e2->set_bits || e1->set_bits & e2->clr_bits)
79 		return false;
80 
81 	if (e1->reg.raw != e2->reg.raw)
82 		return false;
83 
84 	return true;
85 }
86 
87 static void reg_sr_inc_error(struct xe_reg_sr *sr)
88 {
89 #if IS_ENABLED(CONFIG_DRM_XE_KUNIT_TEST)
90 	sr->errors++;
91 #endif
92 }
93 
94 int xe_reg_sr_add(struct xe_reg_sr *sr,
95 		  const struct xe_reg_sr_entry *e,
96 		  struct xe_gt *gt)
97 {
98 	unsigned long idx = e->reg.addr;
99 	struct xe_reg_sr_entry *pentry = xa_load(&sr->xa, idx);
100 	int ret;
101 
102 	if (pentry) {
103 		if (!compatible_entries(pentry, e)) {
104 			ret = -EINVAL;
105 			goto fail;
106 		}
107 
108 		pentry->clr_bits |= e->clr_bits;
109 		pentry->set_bits |= e->set_bits;
110 		pentry->read_mask |= e->read_mask;
111 
112 		return 0;
113 	}
114 
115 	pentry = alloc_entry(sr);
116 	if (!pentry) {
117 		ret = -ENOMEM;
118 		goto fail;
119 	}
120 
121 	*pentry = *e;
122 	ret = xa_err(xa_store(&sr->xa, idx, pentry, GFP_KERNEL));
123 	if (ret)
124 		goto fail;
125 
126 	return 0;
127 
128 fail:
129 	xe_gt_err(gt,
130 		  "discarding save-restore reg %04lx (clear: %08x, set: %08x, masked: %s, mcr: %s): ret=%d\n",
131 		  idx, e->clr_bits, e->set_bits,
132 		  str_yes_no(e->reg.masked),
133 		  str_yes_no(e->reg.mcr),
134 		  ret);
135 	reg_sr_inc_error(sr);
136 
137 	return ret;
138 }
139 
140 /*
141  * Convert back from encoded value to type-safe, only to be used when reg.mcr
142  * is true
143  */
144 static struct xe_reg_mcr to_xe_reg_mcr(const struct xe_reg reg)
145 {
146 	return (const struct xe_reg_mcr){.__reg.raw = reg.raw };
147 }
148 
149 static void apply_one_mmio(struct xe_gt *gt, struct xe_reg_sr_entry *entry)
150 {
151 	struct xe_reg reg = entry->reg;
152 	struct xe_reg_mcr reg_mcr = to_xe_reg_mcr(reg);
153 	u32 val;
154 
155 	/*
156 	 * If this is a masked register, need to set the upper 16 bits.
157 	 * Set them to clr_bits since that is always a superset of the bits
158 	 * being modified.
159 	 *
160 	 * When it's not masked, we have to read it from hardware, unless we are
161 	 * supposed to set all bits.
162 	 */
163 	if (reg.masked)
164 		val = entry->clr_bits << 16;
165 	else if (entry->clr_bits + 1)
166 		val = (reg.mcr ?
167 		       xe_gt_mcr_unicast_read_any(gt, reg_mcr) :
168 		       xe_mmio_read32(&gt->mmio, reg)) & (~entry->clr_bits);
169 	else
170 		val = 0;
171 
172 	/*
173 	 * TODO: add selftest to validate all tables, regardless of platform:
174 	 *   - Masked registers can't have set_bits with upper bits set
175 	 *   - set_bits must be contained in clr_bits
176 	 */
177 	val |= entry->set_bits;
178 
179 	xe_gt_dbg(gt, "REG[0x%x] = 0x%08x", reg.addr, val);
180 
181 	if (entry->reg.mcr)
182 		xe_gt_mcr_multicast_write(gt, reg_mcr, val);
183 	else
184 		xe_mmio_write32(&gt->mmio, reg, val);
185 }
186 
187 void xe_reg_sr_apply_mmio(struct xe_reg_sr *sr, struct xe_gt *gt)
188 {
189 	struct xe_reg_sr_entry *entry;
190 	unsigned long reg;
191 	unsigned int fw_ref;
192 
193 	if (xa_empty(&sr->xa))
194 		return;
195 
196 	xe_gt_dbg(gt, "Applying %s save-restore MMIOs\n", sr->name);
197 
198 	fw_ref = xe_force_wake_get(gt_to_fw(gt), XE_FORCEWAKE_ALL);
199 	if (!xe_force_wake_ref_has_domain(fw_ref, XE_FORCEWAKE_ALL))
200 		goto err_force_wake;
201 
202 	xa_for_each(&sr->xa, reg, entry)
203 		apply_one_mmio(gt, entry);
204 
205 	xe_force_wake_put(gt_to_fw(gt), fw_ref);
206 
207 	return;
208 
209 err_force_wake:
210 	xe_force_wake_put(gt_to_fw(gt), fw_ref);
211 	xe_gt_err(gt, "Failed to apply, err=-ETIMEDOUT\n");
212 }
213 
214 void xe_reg_sr_apply_whitelist(struct xe_hw_engine *hwe)
215 {
216 	struct xe_reg_sr *sr = &hwe->reg_whitelist;
217 	struct xe_gt *gt = hwe->gt;
218 	struct xe_device *xe = gt_to_xe(gt);
219 	struct xe_reg_sr_entry *entry;
220 	struct drm_printer p;
221 	u32 mmio_base = hwe->mmio_base;
222 	unsigned long reg;
223 	unsigned int slot = 0;
224 	unsigned int fw_ref;
225 
226 	if (xa_empty(&sr->xa))
227 		return;
228 
229 	drm_dbg(&xe->drm, "Whitelisting %s registers\n", sr->name);
230 
231 	fw_ref = xe_force_wake_get(gt_to_fw(gt), XE_FORCEWAKE_ALL);
232 	if (!xe_force_wake_ref_has_domain(fw_ref, XE_FORCEWAKE_ALL))
233 		goto err_force_wake;
234 
235 	p = drm_dbg_printer(&xe->drm, DRM_UT_DRIVER, NULL);
236 	xa_for_each(&sr->xa, reg, entry) {
237 		if (slot == RING_MAX_NONPRIV_SLOTS) {
238 			xe_gt_err(gt,
239 				  "hwe %s: maximum register whitelist slots (%d) reached, refusing to add more\n",
240 				  hwe->name, RING_MAX_NONPRIV_SLOTS);
241 			break;
242 		}
243 
244 		xe_reg_whitelist_print_entry(&p, 0, reg, entry);
245 		xe_mmio_write32(&gt->mmio, RING_FORCE_TO_NONPRIV(mmio_base, slot),
246 				reg | entry->set_bits);
247 		slot++;
248 	}
249 
250 	/* And clear the rest just in case of garbage */
251 	for (; slot < RING_MAX_NONPRIV_SLOTS; slot++) {
252 		u32 addr = RING_NOPID(mmio_base).addr;
253 
254 		xe_mmio_write32(&gt->mmio, RING_FORCE_TO_NONPRIV(mmio_base, slot), addr);
255 	}
256 
257 	xe_force_wake_put(gt_to_fw(gt), fw_ref);
258 
259 	return;
260 
261 err_force_wake:
262 	xe_force_wake_put(gt_to_fw(gt), fw_ref);
263 	drm_err(&xe->drm, "Failed to apply, err=-ETIMEDOUT\n");
264 }
265 
266 /**
267  * xe_reg_sr_dump - print all save/restore entries
268  * @sr: Save/restore entries
269  * @p: DRM printer
270  */
271 void xe_reg_sr_dump(struct xe_reg_sr *sr, struct drm_printer *p)
272 {
273 	struct xe_reg_sr_entry *entry;
274 	unsigned long reg;
275 
276 	if (!sr->name || xa_empty(&sr->xa))
277 		return;
278 
279 	drm_printf(p, "%s\n", sr->name);
280 	xa_for_each(&sr->xa, reg, entry)
281 		drm_printf(p, "\tREG[0x%lx] clr=0x%08x set=0x%08x masked=%s mcr=%s\n",
282 			   reg, entry->clr_bits, entry->set_bits,
283 			   str_yes_no(entry->reg.masked),
284 			   str_yes_no(entry->reg.mcr));
285 }
286