/*
* Copyright 2014 Advanced Micro Devices, Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
* OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
* ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
* OTHER DEALINGS IN THE SOFTWARE.
*
*/
#include <linux/device.h>
#include <linux/export.h>
#include <linux/err.h>
#include <linux/fs.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <linux/compat.h>
#include <uapi/linux/kfd_ioctl.h>
#include <linux/time.h>
#include "kfd_priv.h"
#include <linux/mm.h>
#include <linux/mman.h>
#include <asm/processor.h>
/*
* The primary memory I/O features being added for revisions of gfxip
* beyond 7.0 (Kaveri) are:
*
* Access to ATC/IOMMU mapped memory w/ associated extension of VA to 48b
*
* “Flat” shader memory access – These are new shader vector memory
* operations that do not reference a T#/V# so a “pointer” is what is
* sourced from the vector gprs for direct access to memory.
* This pointer space has the Shared(LDS) and Private(Scratch) memory
* mapped into this pointer space as apertures.
* The hardware then determines how to direct the memory request
* based on what apertures the request falls in.
*
* Unaligned support and alignment check
*
*
* System Unified Address - SUA
*
* The standard usage for GPU virtual addresses are that they are mapped by
* a set of page tables we call GPUVM and these page tables are managed by
* a combination of vidMM/driver software components. The current virtual
* address (VA) range for GPUVM is 40b.
*
* As of gfxip7.1 and beyond we’re adding the ability for compute memory
* clients (CP/RLC, DMA, SHADER(ifetch, scalar, and vector ops)) to access
* the same page tables used by host x86 processors and that are managed by
* the operating system. This is via a technique and hardware called ATC/IOMMU.
* The GPU has the capability of accessing both the GPUVM and ATC address
* spaces for a given VMID (process) simultaneously and we call this feature
* system unified address (SUA).
*
* There are three fundamental address modes of operation for a given VMID
* (process) on the GPU:
*
* HSA64 – 64b pointers and the default address space is ATC
* HSA32 – 32b pointers and the default address space is ATC
* GPUVM – 64b pointers and the default address space is GPUVM (driver
* model mode)
*
*
* HSA64 - ATC/IOMMU 64b
*
* A 64b pointer in the AMD64/IA64 CPU architecture is not fully utilized
* by the CPU so an AMD CPU can only access the high area
* (VA[63:47] == 0x1FFFF) and low area (VA[63:47 == 0) of the address space
* so the actual VA carried to translation is 48b. There is a “hole” in
* the middle of the 64b VA space.
*
* The GPU not only has access to all of the CPU accessible address space via
* ATC/IOMMU, but it also has access to the GPUVM address space. The “system
* unified address” feature (SUA) is the mapping of GPUVM and ATC address
* spaces into a unified pointer space. The method we take for 64b mode is
* to map the full 40b GPUVM address space into the hole of the 64b address
* space.
* The GPUVM_Base/GPUVM_Limit defines the aperture in the 64b space where we
* direct requests to be translated via GPUVM page tables instead of the
* IOMMU path.
*
*
* 64b to 49b Address conversion
*
* Note that there are still significant portions of unused regions (holes)
* in the 64b address space even for the GPU. There are several places in
* the pipeline (sw and hw), we wish to compress the 64b virtual address
* to a 49b address. This 49b address is constituted of an “ATC” bit
* plus a 48b virtual address. This 49b address is what is passed to the
* translation hardware. ATC==0 means the 48b address is a GPUVM address
* (max of 2^40 – 1) intended to be translated via GPUVM page tables.
* ATC==1 means the 48b address is intended to be translated via IOMMU
* page tables.
*
* A 64b pointer is compared to the apertures that are defined (Base/Limit), in
* this case the GPUVM aperture (red) is defined and if a pointer falls in this
* aperture, we subtract the GPUVM_Base address and set the ATC bit to zero
* as part of the 64b to 49b conversion.
*
* Where this 64b to 49b conversion is done is a function of the usage.
* Most GPU memory access is via memory objects where the driver builds
* a descriptor which consists of a base address and a memory access by
* the GPU usually consists of some kind of an offset or Cartesian coordinate
* that references this memory descriptor. This is the case for shader
* instructions that reference the T# or V# constants, or for specified
* locations of assets (ex. the shader program location). In these cases
* the driver is what handles the 64b to 49b conversion and the base
* address in the descriptor (ex. V# or T# or shader program location)
* is defined as a 48b address w/ an ATC bit. For this usage a given
* memory object cannot straddle multiple apertures in the 64b address
* space. For example a shader program cannot jump in/out between ATC
* and GPUVM space.
*
* In some cases we wish to pass a 64b pointer to the GPU hardware and
* the GPU hw does the 64b to 49b conversion before passing memory
* requests to the cache/memory system. This is the case for the
* S_LOAD and FLAT_* shader memory instructions where we have 64b pointers
* in scalar and vector GPRs respectively.
*
* In all cases (no matter where the 64b -> 49b conversion is done), the gfxip
* hardware sends a 48b address along w/ an ATC bit, to the memory controller
* on the memory request interfaces.
*
* <client>_MC_rdreq_atc // read request ATC bit
*
* 0 : <client>_MC_rdreq_addr is a GPUVM VA
*
* 1 : <client>_MC_rdreq_addr is a ATC VA
*
*
* “Spare” aperture (APE1)
*
* We use the GPUVM aperture to differentiate ATC vs. GPUVM, but we also use
* apertures to set the Mtype field for S_LOAD/FLAT_* ops which is input to the
* config tables for setting cache policies. The “spare” (APE1) aperture is
* motivated by getting a different Mtype from the default.
* The default aperture isn’t an actual base/limit aperture; it is just the
* address space that doesn’t hit any defined base/limit apertures.
* The following diagram is a complete picture of the gfxip7.x SUA apertures.
* The APE1 can be placed either below or above
* the hole (cannot be in the hole).
*
*
* General Aperture definitions and rules
*
* An aperture register definition consists of a Base, Limit, Mtype, and
* usually an ATC bit indicating which translation tables that aperture uses.
* In all cases (for SUA and DUA apertures discussed later), aperture base
* and limit definitions are 64KB aligned.
*
* <ape>_Base[63:0] = { <ape>_Base_register[63:16], 0x0000 }
*
* <ape>_Limit[63:0] = { <ape>_Limit_register[63:16], 0xFFFF }
*
* The base and limit are considered inclusive to an aperture so being
* inside an aperture means (address >= Base) AND (address <= Limit).
*
* In no case is a payload that straddles multiple apertures expected to work.
* For example a load_dword_x4 that starts in one aperture and ends in another,
* does not work. For the vector FLAT_* ops we have detection capability in
* the shader for reporting a “memory violation” back to the
* SQ block for use in traps.
* A memory violation results when an op falls into the hole,
* or a payload straddles multiple apertures. The S_LOAD instruction
* does not have this detection.
*
* Apertures cannot overlap.
*
*
*
* HSA32 - ATC/IOMMU 32b
*
* For HSA32 mode, the pointers are interpreted as 32 bits and use a single GPR
* instead of two for the S_LOAD and FLAT_* ops. The entire GPUVM space of 40b
* will not fit so there is only partial visibility to the GPUVM
* space (defined by the aperture) for S_LOAD and FLAT_* ops.
* There is no spare (APE1) aperture for HSA32 mode.
*
*
* GPUVM 64b mode (driver model)
*
* This mode is related to HSA64 in that the difference really is that
* the default aperture is GPUVM (ATC==0) and not ATC space.
* We have gfxip7.x hardware that has FLAT_* and S_LOAD support for
* SUA GPUVM mode, but does not support HSA32/HSA64.
*
*
* Device Unified Address - DUA
*
* Device unified address (DUA) is the name of the feature that maps the
* Shared(LDS) memory and Private(Scratch) memory into the overall address
* space for use by the new FLAT_* vector memory ops. The Shared and
* Private memories are mapped as apertures into the address space,
* and the hardware detects when a FLAT_* memory request is to be redirected
* to the LDS or Scratch memory when it falls into one of these apertures.
* Like the SUA apertures, the Shared/Private apertures are 64KB aligned and
* the base/limit is “in” the aperture. For both HSA64 and GPUVM SUA modes,
* the Shared/Private apertures are always placed in a limited selection of
* options in the hole of the 64b address space. For HSA32 mode, the
* Shared/Private apertures can be placed anywhere in the 32b space
* except at 0.
*
*
* HSA64 Apertures for FLAT_* vector ops
*
* For HSA64 SUA mode, the Shared and Private apertures are always placed
* in the hole w/ a limited selection of possible locations. The requests
* that fall in the private aperture are expanded as a function of the
* work-item id (tid) and redirected to the location of the
* “hidden private memory”. The hidden private can be placed in either GPUVM
* or ATC space. The addresses that fall in the shared aperture are
* re-directed to the on-chip LDS memory hardware.
*
*
* HSA32 Apertures for FLAT_* vector ops
*
* In HSA32 mode, the Private and Shared apertures can be placed anywhere
* in the 32b space except at 0 (Private or Shared Base at zero disables
* the apertures). If the base address of the apertures are non-zero
* (ie apertures exists), the size is always 64KB.
*
*
* GPUVM Apertures for FLAT_* vector ops
*
* In GPUVM mode, the Shared/Private apertures are specified identically
* to HSA64 mode where they are always in the hole at a limited selection
* of locations.
*
*
* Aperture Definitions for SUA and DUA
*
* The interpretation of the aperture register definitions for a given
* VMID is a function of the “SUA Mode” which is one of HSA64, HSA32, or
* GPUVM64 discussed in previous sections. The mode is first decoded, and
* then the remaining register decode is a function of the mode.
*
*
* SUA Mode Decode
*
* For the S_LOAD and FLAT_* shader operations, the SUA mode is decoded from
* the COMPUTE_DISPATCH_INITIATOR:DATA_ATC bit and
* the SH_MEM_CONFIG:PTR32 bits.
*
* COMPUTE_DISPATCH_INITIATOR:DATA_ATC SH_MEM_CONFIG:PTR32 Mode
*
* 1 0 HSA64
*
* 1 1 HSA32
*
* 0 X GPUVM64
*
* In general the hardware will ignore the PTR32 bit and treat
* as “0” whenever DATA_ATC = “0”, but sw should set PTR32=0
* when DATA_ATC=0.
*
* The DATA_ATC bit is only set for compute dispatches.
* All “Draw” dispatches are hardcoded to GPUVM64 mode
* for FLAT_* / S_LOAD operations.
*/
#define MAKE_GPUVM_APP_BASE(gpu_num) \
(((uint64_t)(gpu_num) << 61) + 0x1000000000000L)
#define MAKE_GPUVM_APP_LIMIT(base) \
(((uint64_t)(base) & \
0xFFFFFF0000000000UL) | 0xFFFFFFFFFFL)
#define MAKE_SCRATCH_APP_BASE(gpu_num) \
(((uint64_t)(gpu_num) << 61) + 0x100000000L)
#define MAKE_SCRATCH_APP_LIMIT(base) \
(((uint64_t)base & 0xFFFFFFFF00000000UL) | 0xFFFFFFFF)
#define MAKE_LDS_APP_BASE(gpu_num) \
(((uint64_t)(gpu_num) << 61) + 0x0)
#define MAKE_LDS_APP_LIMIT(base) \
(((uint64_t)(base) & 0xFFFFFFFF00000000UL) | 0xFFFFFFFF)
int kfd_init_apertures(struct kfd_process *process)
{
uint8_t id = 0;
struct kfd_dev *dev;
struct kfd_process_device *pdd;
/*Iterating over all devices*/
while (kfd_topology_enum_kfd_devices(id, &dev) == 0 &&
id < NUM_OF_SUPPORTED_GPUS) {
if (!dev) {
id++; /* Skip non GPU devices */
continue;
}
pdd = kfd_create_process_device_data(dev, process);
if (!pdd) {
pr_err("Failed to create process device data\n");
return -1;
}
/*
* For 64 bit process aperture will be statically reserved in
* the x86_64 non canonical process address space
* amdkfd doesn't currently support apertures for 32 bit process
*/
if (process->is_32bit_user_mode) {
pdd->lds_base = pdd->lds_limit = 0;
pdd->gpuvm_base = pdd->gpuvm_limit = 0;
pdd->scratch_base = pdd->scratch_limit = 0;
} else {
/*
* node id couldn't be 0 - the three MSB bits of
* aperture shoudn't be 0
*/
pdd->lds_base = MAKE_LDS_APP_BASE(id + 1);
pdd->lds_limit = MAKE_LDS_APP_LIMIT(pdd->lds_base);
pdd->gpuvm_base = MAKE_GPUVM_APP_BASE(id + 1);
pdd->gpuvm_limit =
MAKE_GPUVM_APP_LIMIT(pdd->gpuvm_base);
pdd->scratch_base = MAKE_SCRATCH_APP_BASE(id + 1);
pdd->scratch_limit =
MAKE_SCRATCH_APP_LIMIT(pdd->scratch_base);
}
dev_dbg(kfd_device, "node id %u\n", id);
dev_dbg(kfd_device, "gpu id %u\n", pdd->dev->id);
dev_dbg(kfd_device, "lds_base %llX\n", pdd->lds_base);
dev_dbg(kfd_device, "lds_limit %llX\n", pdd->lds_limit);
dev_dbg(kfd_device, "gpuvm_base %llX\n", pdd->gpuvm_base);
dev_dbg(kfd_device, "gpuvm_limit %llX\n", pdd->gpuvm_limit);
dev_dbg(kfd_device, "scratch_base %llX\n", pdd->scratch_base);
dev_dbg(kfd_device, "scratch_limit %llX\n", pdd->scratch_limit);
id++;
}
return 0;
}
