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