| /* |
| * Copyright 2018 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. |
| * |
| * Authors: AMD |
| * |
| */ |
| |
| #include "vm_helper.h" |
| |
| static void mark_vmid_used(struct vm_helper *vm_helper, unsigned int pos, uint8_t hubp_idx) |
| { |
| struct vmid_usage vmids = vm_helper->hubp_vmid_usage[hubp_idx]; |
| |
| vmids.vmid_usage[0] = vmids.vmid_usage[1]; |
| vmids.vmid_usage[1] = 1 << pos; |
| } |
| |
| static void add_ptb_to_table(struct vm_helper *vm_helper, unsigned int vmid, uint64_t ptb) |
| { |
| vm_helper->ptb_assigned_to_vmid[vmid] = ptb; |
| vm_helper->num_vmids_available--; |
| } |
| |
| static void clear_entry_from_vmid_table(struct vm_helper *vm_helper, unsigned int vmid) |
| { |
| vm_helper->ptb_assigned_to_vmid[vmid] = 0; |
| vm_helper->num_vmids_available++; |
| } |
| |
| static void evict_vmids(struct vm_helper *vm_helper) |
| { |
| int i; |
| uint16_t ord = 0; |
| |
| for (i = 0; i < vm_helper->num_vmid; i++) |
| ord |= vm_helper->hubp_vmid_usage[i].vmid_usage[0] | vm_helper->hubp_vmid_usage[i].vmid_usage[1]; |
| |
| // At this point any positions with value 0 are unused vmids, evict them |
| for (i = 1; i < vm_helper->num_vmid; i++) { |
| if (ord & (1u << i)) |
| clear_entry_from_vmid_table(vm_helper, i); |
| } |
| } |
| |
| // Return value of -1 indicates vmid table unitialized or ptb dne in the table |
| static int get_existing_vmid_for_ptb(struct vm_helper *vm_helper, uint64_t ptb) |
| { |
| int i; |
| |
| for (i = 0; i < vm_helper->num_vmid; i++) { |
| if (vm_helper->ptb_assigned_to_vmid[i] == ptb) |
| return i; |
| } |
| |
| return -1; |
| } |
| |
| // Expected to be called only when there's an available vmid |
| static int get_next_available_vmid(struct vm_helper *vm_helper) |
| { |
| int i; |
| |
| for (i = 1; i < vm_helper->num_vmid; i++) { |
| if (vm_helper->ptb_assigned_to_vmid[i] == 0) |
| return i; |
| } |
| |
| return -1; |
| } |
| |
| uint8_t get_vmid_for_ptb(struct vm_helper *vm_helper, int64_t ptb, uint8_t hubp_idx) |
| { |
| unsigned int vmid = 0; |
| int vmid_exists = -1; |
| |
| // Physical address gets vmid 0 |
| if (ptb == 0) |
| return 0; |
| |
| vmid_exists = get_existing_vmid_for_ptb(vm_helper, ptb); |
| |
| if (vmid_exists != -1) { |
| mark_vmid_used(vm_helper, vmid_exists, hubp_idx); |
| vmid = vmid_exists; |
| } else { |
| if (vm_helper->num_vmids_available == 0) |
| evict_vmids(vm_helper); |
| |
| vmid = get_next_available_vmid(vm_helper); |
| mark_vmid_used(vm_helper, vmid, hubp_idx); |
| add_ptb_to_table(vm_helper, vmid, ptb); |
| } |
| |
| return vmid; |
| } |
| |
| void init_vm_helper(struct vm_helper *vm_helper, unsigned int num_vmid, unsigned int num_hubp) |
| { |
| vm_helper->num_vmid = num_vmid; |
| vm_helper->num_hubp = num_hubp; |
| vm_helper->num_vmids_available = num_vmid - 1; |
| |
| memset(vm_helper->hubp_vmid_usage, 0, sizeof(vm_helper->hubp_vmid_usage[0]) * MAX_HUBP); |
| memset(vm_helper->ptb_assigned_to_vmid, 0, sizeof(vm_helper->ptb_assigned_to_vmid[0]) * MAX_VMID); |
| } |