1// SPDX-License-Identifier: GPL-2.0 OR MIT
2/*
3 * Copyright 2014-2022 Advanced Micro Devices, Inc.
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be included in
13 * all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
19 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
20 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
21 * OTHER DEALINGS IN THE SOFTWARE.
22 *
23 */
24
25#include <linux/device.h>
26#include <linux/err.h>
27#include <linux/fs.h>
28#include <linux/sched.h>
29#include <linux/slab.h>
30#include <linux/uaccess.h>
31#include <linux/compat.h>
32#include <uapi/linux/kfd_ioctl.h>
33#include <linux/time.h>
34#include "kfd_priv.h"
35#include <linux/mm.h>
36#include <linux/mman.h>
37#include <linux/processor.h>
38#include "amdgpu_vm.h"
39
40/*
41 * The primary memory I/O features being added for revisions of gfxip
42 * beyond 7.0 (Kaveri) are:
43 *
44 * Access to ATC/IOMMU mapped memory w/ associated extension of VA to 48b
45 *
46 * “Flat” shader memory access – These are new shader vector memory
47 * operations that do not reference a T#/V# so a “pointer” is what is
48 * sourced from the vector gprs for direct access to memory.
49 * This pointer space has the Shared(LDS) and Private(Scratch) memory
50 * mapped into this pointer space as apertures.
51 * The hardware then determines how to direct the memory request
52 * based on what apertures the request falls in.
53 *
54 * Unaligned support and alignment check
55 *
56 *
57 * System Unified Address - SUA
58 *
59 * The standard usage for GPU virtual addresses are that they are mapped by
60 * a set of page tables we call GPUVM and these page tables are managed by
61 * a combination of vidMM/driver software components. The current virtual
62 * address (VA) range for GPUVM is 40b.
63 *
64 * As of gfxip7.1 and beyond we’re adding the ability for compute memory
65 * clients (CP/RLC, DMA, SHADER(ifetch, scalar, and vector ops)) to access
66 * the same page tables used by host x86 processors and that are managed by
67 * the operating system. This is via a technique and hardware called ATC/IOMMU.
68 * The GPU has the capability of accessing both the GPUVM and ATC address
69 * spaces for a given VMID (process) simultaneously and we call this feature
70 * system unified address (SUA).
71 *
72 * There are three fundamental address modes of operation for a given VMID
73 * (process) on the GPU:
74 *
75 * HSA64 – 64b pointers and the default address space is ATC
76 * HSA32 – 32b pointers and the default address space is ATC
77 * GPUVM – 64b pointers and the default address space is GPUVM (driver
78 * model mode)
79 *
80 *
81 * HSA64 - ATC/IOMMU 64b
82 *
83 * A 64b pointer in the AMD64/IA64 CPU architecture is not fully utilized
84 * by the CPU so an AMD CPU can only access the high area
85 * (VA[63:47] == 0x1FFFF) and low area (VA[63:47 == 0) of the address space
86 * so the actual VA carried to translation is 48b. There is a “hole” in
87 * the middle of the 64b VA space.
88 *
89 * The GPU not only has access to all of the CPU accessible address space via
90 * ATC/IOMMU, but it also has access to the GPUVM address space. The “system
91 * unified address” feature (SUA) is the mapping of GPUVM and ATC address
92 * spaces into a unified pointer space. The method we take for 64b mode is
93 * to map the full 40b GPUVM address space into the hole of the 64b address
94 * space.
95
96 * The GPUVM_Base/GPUVM_Limit defines the aperture in the 64b space where we
97 * direct requests to be translated via GPUVM page tables instead of the
98 * IOMMU path.
99 *
100 *
101 * 64b to 49b Address conversion
102 *
103 * Note that there are still significant portions of unused regions (holes)
104 * in the 64b address space even for the GPU. There are several places in
105 * the pipeline (sw and hw), we wish to compress the 64b virtual address
106 * to a 49b address. This 49b address is constituted of an “ATC” bit
107 * plus a 48b virtual address. This 49b address is what is passed to the
108 * translation hardware. ATC==0 means the 48b address is a GPUVM address
109 * (max of 2^40 – 1) intended to be translated via GPUVM page tables.
110 * ATC==1 means the 48b address is intended to be translated via IOMMU
111 * page tables.
112 *
113 * A 64b pointer is compared to the apertures that are defined (Base/Limit), in
114 * this case the GPUVM aperture (red) is defined and if a pointer falls in this
115 * aperture, we subtract the GPUVM_Base address and set the ATC bit to zero
116 * as part of the 64b to 49b conversion.
117 *
118 * Where this 64b to 49b conversion is done is a function of the usage.
119 * Most GPU memory access is via memory objects where the driver builds
120 * a descriptor which consists of a base address and a memory access by
121 * the GPU usually consists of some kind of an offset or Cartesian coordinate
122 * that references this memory descriptor. This is the case for shader
123 * instructions that reference the T# or V# constants, or for specified
124 * locations of assets (ex. the shader program location). In these cases
125 * the driver is what handles the 64b to 49b conversion and the base
126 * address in the descriptor (ex. V# or T# or shader program location)
127 * is defined as a 48b address w/ an ATC bit. For this usage a given
128 * memory object cannot straddle multiple apertures in the 64b address
129 * space. For example a shader program cannot jump in/out between ATC
130 * and GPUVM space.
131 *
132 * In some cases we wish to pass a 64b pointer to the GPU hardware and
133 * the GPU hw does the 64b to 49b conversion before passing memory
134 * requests to the cache/memory system. This is the case for the
135 * S_LOAD and FLAT_* shader memory instructions where we have 64b pointers
136 * in scalar and vector GPRs respectively.
137 *
138 * In all cases (no matter where the 64b -> 49b conversion is done), the gfxip
139 * hardware sends a 48b address along w/ an ATC bit, to the memory controller
140 * on the memory request interfaces.
141 *
142 * <client>_MC_rdreq_atc // read request ATC bit
143 *
144 * 0 : <client>_MC_rdreq_addr is a GPUVM VA
145 *
146 * 1 : <client>_MC_rdreq_addr is a ATC VA
147 *
148 *
149 * “Spare” aperture (APE1)
150 *
151 * We use the GPUVM aperture to differentiate ATC vs. GPUVM, but we also use
152 * apertures to set the Mtype field for S_LOAD/FLAT_* ops which is input to the
153 * config tables for setting cache policies. The “spare” (APE1) aperture is
154 * motivated by getting a different Mtype from the default.
155 * The default aperture isn’t an actual base/limit aperture; it is just the
156 * address space that doesn’t hit any defined base/limit apertures.
157 * The following diagram is a complete picture of the gfxip7.x SUA apertures.
158 * The APE1 can be placed either below or above
159 * the hole (cannot be in the hole).
160 *
161 *
162 * General Aperture definitions and rules
163 *
164 * An aperture register definition consists of a Base, Limit, Mtype, and
165 * usually an ATC bit indicating which translation tables that aperture uses.
166 * In all cases (for SUA and DUA apertures discussed later), aperture base
167 * and limit definitions are 64KB aligned.
168 *
169 * <ape>_Base[63:0] = { <ape>_Base_register[63:16], 0x0000 }
170 *
171 * <ape>_Limit[63:0] = { <ape>_Limit_register[63:16], 0xFFFF }
172 *
173 * The base and limit are considered inclusive to an aperture so being
174 * inside an aperture means (address >= Base) AND (address <= Limit).
175 *
176 * In no case is a payload that straddles multiple apertures expected to work.
177 * For example a load_dword_x4 that starts in one aperture and ends in another,
178 * does not work. For the vector FLAT_* ops we have detection capability in
179 * the shader for reporting a “memory violation” back to the
180 * SQ block for use in traps.
181 * A memory violation results when an op falls into the hole,
182 * or a payload straddles multiple apertures. The S_LOAD instruction
183 * does not have this detection.
184 *
185 * Apertures cannot overlap.
186 *
187 *
188 *
189 * HSA32 - ATC/IOMMU 32b
190 *
191 * For HSA32 mode, the pointers are interpreted as 32 bits and use a single GPR
192 * instead of two for the S_LOAD and FLAT_* ops. The entire GPUVM space of 40b
193 * will not fit so there is only partial visibility to the GPUVM
194 * space (defined by the aperture) for S_LOAD and FLAT_* ops.
195 * There is no spare (APE1) aperture for HSA32 mode.
196 *
197 *
198 * GPUVM 64b mode (driver model)
199 *
200 * This mode is related to HSA64 in that the difference really is that
201 * the default aperture is GPUVM (ATC==0) and not ATC space.
202 * We have gfxip7.x hardware that has FLAT_* and S_LOAD support for
203 * SUA GPUVM mode, but does not support HSA32/HSA64.
204 *
205 *
206 * Device Unified Address - DUA
207 *
208 * Device unified address (DUA) is the name of the feature that maps the
209 * Shared(LDS) memory and Private(Scratch) memory into the overall address
210 * space for use by the new FLAT_* vector memory ops. The Shared and
211 * Private memories are mapped as apertures into the address space,
212 * and the hardware detects when a FLAT_* memory request is to be redirected
213 * to the LDS or Scratch memory when it falls into one of these apertures.
214 * Like the SUA apertures, the Shared/Private apertures are 64KB aligned and
215 * the base/limit is “in” the aperture. For both HSA64 and GPUVM SUA modes,
216 * the Shared/Private apertures are always placed in a limited selection of
217 * options in the hole of the 64b address space. For HSA32 mode, the
218 * Shared/Private apertures can be placed anywhere in the 32b space
219 * except at 0.
220 *
221 *
222 * HSA64 Apertures for FLAT_* vector ops
223 *
224 * For HSA64 SUA mode, the Shared and Private apertures are always placed
225 * in the hole w/ a limited selection of possible locations. The requests
226 * that fall in the private aperture are expanded as a function of the
227 * work-item id (tid) and redirected to the location of the
228 * “hidden private memory”. The hidden private can be placed in either GPUVM
229 * or ATC space. The addresses that fall in the shared aperture are
230 * re-directed to the on-chip LDS memory hardware.
231 *
232 *
233 * HSA32 Apertures for FLAT_* vector ops
234 *
235 * In HSA32 mode, the Private and Shared apertures can be placed anywhere
236 * in the 32b space except at 0 (Private or Shared Base at zero disables
237 * the apertures). If the base address of the apertures are non-zero
238 * (ie apertures exists), the size is always 64KB.
239 *
240 *
241 * GPUVM Apertures for FLAT_* vector ops
242 *
243 * In GPUVM mode, the Shared/Private apertures are specified identically
244 * to HSA64 mode where they are always in the hole at a limited selection
245 * of locations.
246 *
247 *
248 * Aperture Definitions for SUA and DUA
249 *
250 * The interpretation of the aperture register definitions for a given
251 * VMID is a function of the “SUA Mode” which is one of HSA64, HSA32, or
252 * GPUVM64 discussed in previous sections. The mode is first decoded, and
253 * then the remaining register decode is a function of the mode.
254 *
255 *
256 * SUA Mode Decode
257 *
258 * For the S_LOAD and FLAT_* shader operations, the SUA mode is decoded from
259 * the COMPUTE_DISPATCH_INITIATOR:DATA_ATC bit and
260 * the SH_MEM_CONFIG:PTR32 bits.
261 *
262 * COMPUTE_DISPATCH_INITIATOR:DATA_ATC SH_MEM_CONFIG:PTR32 Mode
263 *
264 * 1 0 HSA64
265 *
266 * 1 1 HSA32
267 *
268 * 0 X GPUVM64
269 *
270 * In general the hardware will ignore the PTR32 bit and treat
271 * as “0” whenever DATA_ATC = “0”, but sw should set PTR32=0
272 * when DATA_ATC=0.
273 *
274 * The DATA_ATC bit is only set for compute dispatches.
275 * All “Draw” dispatches are hardcoded to GPUVM64 mode
276 * for FLAT_* / S_LOAD operations.
277 */
278
279#define MAKE_GPUVM_APP_BASE_VI(gpu_num) \
280 (((uint64_t)(gpu_num) << 61) + 0x1000000000000L)
281
282#define MAKE_GPUVM_APP_LIMIT(base, size) \
283 (((uint64_t)(base) & 0xFFFFFF0000000000UL) + (size) - 1)
284
285#define MAKE_SCRATCH_APP_BASE_VI() \
286 (((uint64_t)(0x1UL) << 61) + 0x100000000L)
287
288#define MAKE_SCRATCH_APP_LIMIT(base) \
289 (((uint64_t)base & 0xFFFFFFFF00000000UL) | 0xFFFFFFFF)
290
291#define MAKE_LDS_APP_BASE_VI() \
292 (((uint64_t)(0x1UL) << 61) + 0x0)
293#define MAKE_LDS_APP_LIMIT(base) \
294 (((uint64_t)(base) & 0xFFFFFFFF00000000UL) | 0xFFFFFFFF)
295
296/* On GFXv9 the LDS and scratch apertures are programmed independently
297 * using the high 16 bits of the 64-bit virtual address. They must be
298 * in the hole, which will be the case as long as the high 16 bits are
299 * not 0.
300 *
301 * The aperture sizes are still 4GB implicitly.
302 *
303 * A GPUVM aperture is not applicable on GFXv9.
304 */
305#define MAKE_LDS_APP_BASE_V9() ((uint64_t)(0x1UL) << 48)
306#define MAKE_SCRATCH_APP_BASE_V9() ((uint64_t)(0x2UL) << 48)
307
308/* User mode manages most of the SVM aperture address space. The low
309 * 16MB are reserved for kernel use (CWSR trap handler and kernel IB
310 * for now).
311 */
312#define SVM_USER_BASE (u64)(KFD_CWSR_TBA_TMA_SIZE + 2*PAGE_SIZE)
313#define SVM_CWSR_BASE (SVM_USER_BASE - KFD_CWSR_TBA_TMA_SIZE)
314#define SVM_IB_BASE (SVM_CWSR_BASE - PAGE_SIZE)
315
316static void kfd_init_apertures_vi(struct kfd_process_device *pdd, uint8_t id)
317{
318 /*
319 * node id couldn't be 0 - the three MSB bits of
320 * aperture shouldn't be 0
321 */
322 pdd->lds_base = MAKE_LDS_APP_BASE_VI();
323 pdd->lds_limit = MAKE_LDS_APP_LIMIT(pdd->lds_base);
324
325 /* dGPUs: SVM aperture starting at 0
326 * with small reserved space for kernel.
327 * Set them to CANONICAL addresses.
328 */
329 pdd->gpuvm_base = max(SVM_USER_BASE, AMDGPU_VA_RESERVED_BOTTOM);
330 pdd->gpuvm_limit =
331 pdd->dev->kfd->shared_resources.gpuvm_size - 1;
332
333 /* dGPUs: the reserved space for kernel
334 * before SVM
335 */
336 pdd->qpd.cwsr_base = SVM_CWSR_BASE;
337 pdd->qpd.ib_base = SVM_IB_BASE;
338
339 pdd->scratch_base = MAKE_SCRATCH_APP_BASE_VI();
340 pdd->scratch_limit = MAKE_SCRATCH_APP_LIMIT(pdd->scratch_base);
341}
342
343static void kfd_init_apertures_v9(struct kfd_process_device *pdd, uint8_t id)
344{
345 pdd->lds_base = MAKE_LDS_APP_BASE_V9();
346 pdd->lds_limit = MAKE_LDS_APP_LIMIT(pdd->lds_base);
347
348 pdd->gpuvm_base = AMDGPU_VA_RESERVED_BOTTOM;
349 pdd->gpuvm_limit =
350 pdd->dev->kfd->shared_resources.gpuvm_size - 1;
351
352 pdd->scratch_base = MAKE_SCRATCH_APP_BASE_V9();
353 pdd->scratch_limit = MAKE_SCRATCH_APP_LIMIT(pdd->scratch_base);
354
355 /*
356 * Place TBA/TMA on opposite side of VM hole to prevent
357 * stray faults from triggering SVM on these pages.
358 */
359 pdd->qpd.cwsr_base = AMDGPU_VA_RESERVED_TRAP_START(pdd->dev->adev);
360}
361
362int kfd_init_apertures(struct kfd_process *process)
363{
364 uint8_t id = 0;
365 struct kfd_node *dev;
366 struct kfd_process_device *pdd;
367
368 /*Iterating over all devices*/
369 while (kfd_topology_enum_kfd_devices(idx: id, kdev: &dev) == 0) {
370 if (!dev || kfd_devcgroup_check_permission(node: dev)) {
371 /* Skip non GPU devices and devices to which the
372 * current process have no access to. Access can be
373 * limited by placing the process in a specific
374 * cgroup hierarchy
375 */
376 id++;
377 continue;
378 }
379
380 pdd = kfd_create_process_device_data(dev, p: process);
381 if (!pdd) {
382 dev_err(dev->adev->dev,
383 "Failed to create process device data\n");
384 return -ENOMEM;
385 }
386 /*
387 * For 64 bit process apertures will be statically reserved in
388 * the x86_64 non canonical process address space
389 * amdkfd doesn't currently support apertures for 32 bit process
390 */
391 if (process->is_32bit_user_mode) {
392 pdd->lds_base = pdd->lds_limit = 0;
393 pdd->gpuvm_base = pdd->gpuvm_limit = 0;
394 pdd->scratch_base = pdd->scratch_limit = 0;
395 } else {
396 switch (dev->adev->asic_type) {
397 case CHIP_KAVERI:
398 case CHIP_HAWAII:
399 case CHIP_CARRIZO:
400 case CHIP_TONGA:
401 case CHIP_FIJI:
402 case CHIP_POLARIS10:
403 case CHIP_POLARIS11:
404 case CHIP_POLARIS12:
405 case CHIP_VEGAM:
406 kfd_init_apertures_vi(pdd, id);
407 break;
408 default:
409 if (KFD_GC_VERSION(dev) >= IP_VERSION(9, 0, 1))
410 kfd_init_apertures_v9(pdd, id);
411 else {
412 WARN(1, "Unexpected ASIC family %u",
413 dev->adev->asic_type);
414 return -EINVAL;
415 }
416 }
417 }
418
419 dev_dbg(kfd_device, "node id %u\n", id);
420 dev_dbg(kfd_device, "gpu id %u\n", pdd->dev->id);
421 dev_dbg(kfd_device, "lds_base %llX\n", pdd->lds_base);
422 dev_dbg(kfd_device, "lds_limit %llX\n", pdd->lds_limit);
423 dev_dbg(kfd_device, "gpuvm_base %llX\n", pdd->gpuvm_base);
424 dev_dbg(kfd_device, "gpuvm_limit %llX\n", pdd->gpuvm_limit);
425 dev_dbg(kfd_device, "scratch_base %llX\n", pdd->scratch_base);
426 dev_dbg(kfd_device, "scratch_limit %llX\n", pdd->scratch_limit);
427
428 id++;
429 }
430
431 return 0;
432}
433

source code of linux/drivers/gpu/drm/amd/amdkfd/kfd_flat_memory.c