linux/drivers/gpu/drm/amd/include/amd_pcie_helpers.h

142 lines
3.9 KiB
C

/*
* Copyright 2015 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.
*/
#ifndef __AMD_PCIE_HELPERS_H__
#define __AMD_PCIE_HELPERS_H__
#include "amd_pcie.h"
static inline bool is_pcie_gen3_supported(uint32_t pcie_link_speed_cap)
{
if (pcie_link_speed_cap & CAIL_PCIE_LINK_SPEED_SUPPORT_GEN3)
return true;
return false;
}
static inline bool is_pcie_gen2_supported(uint32_t pcie_link_speed_cap)
{
if (pcie_link_speed_cap & CAIL_PCIE_LINK_SPEED_SUPPORT_GEN2)
return true;
return false;
}
/* Get the new PCIE speed given the ASIC PCIE Cap and the NewState's requested PCIE speed*/
static inline uint16_t get_pcie_gen_support(uint32_t pcie_link_speed_cap,
uint16_t ns_pcie_gen)
{
uint32_t asic_pcie_link_speed_cap = (pcie_link_speed_cap &
CAIL_ASIC_PCIE_LINK_SPEED_SUPPORT_MASK);
uint32_t sys_pcie_link_speed_cap = (pcie_link_speed_cap &
CAIL_PCIE_LINK_SPEED_SUPPORT_MASK);
switch (asic_pcie_link_speed_cap) {
case CAIL_ASIC_PCIE_LINK_SPEED_SUPPORT_GEN1:
return PP_PCIEGen1;
case CAIL_ASIC_PCIE_LINK_SPEED_SUPPORT_GEN2:
return PP_PCIEGen2;
case CAIL_ASIC_PCIE_LINK_SPEED_SUPPORT_GEN3:
return PP_PCIEGen3;
default:
if (is_pcie_gen3_supported(sys_pcie_link_speed_cap) &&
(ns_pcie_gen == PP_PCIEGen3)) {
return PP_PCIEGen3;
} else if (is_pcie_gen2_supported(sys_pcie_link_speed_cap) &&
((ns_pcie_gen == PP_PCIEGen3) || (ns_pcie_gen == PP_PCIEGen2))) {
return PP_PCIEGen2;
}
}
return PP_PCIEGen1;
}
static inline uint16_t get_pcie_lane_support(uint32_t pcie_lane_width_cap,
uint16_t ns_pcie_lanes)
{
int i, j;
uint16_t new_pcie_lanes = ns_pcie_lanes;
uint16_t pcie_lanes[7] = {1, 2, 4, 8, 12, 16, 32};
switch (pcie_lane_width_cap) {
case 0:
printk(KERN_ERR "No valid PCIE lane width reported");
break;
case CAIL_PCIE_LINK_WIDTH_SUPPORT_X1:
new_pcie_lanes = 1;
break;
case CAIL_PCIE_LINK_WIDTH_SUPPORT_X2:
new_pcie_lanes = 2;
break;
case CAIL_PCIE_LINK_WIDTH_SUPPORT_X4:
new_pcie_lanes = 4;
break;
case CAIL_PCIE_LINK_WIDTH_SUPPORT_X8:
new_pcie_lanes = 8;
break;
case CAIL_PCIE_LINK_WIDTH_SUPPORT_X12:
new_pcie_lanes = 12;
break;
case CAIL_PCIE_LINK_WIDTH_SUPPORT_X16:
new_pcie_lanes = 16;
break;
case CAIL_PCIE_LINK_WIDTH_SUPPORT_X32:
new_pcie_lanes = 32;
break;
default:
for (i = 0; i < 7; i++) {
if (ns_pcie_lanes == pcie_lanes[i]) {
if (pcie_lane_width_cap & (0x10000 << i)) {
break;
} else {
for (j = i - 1; j >= 0; j--) {
if (pcie_lane_width_cap & (0x10000 << j)) {
new_pcie_lanes = pcie_lanes[j];
break;
}
}
if (j < 0) {
for (j = i + 1; j < 7; j++) {
if (pcie_lane_width_cap & (0x10000 << j)) {
new_pcie_lanes = pcie_lanes[j];
break;
}
}
if (j > 7)
printk(KERN_ERR "Cannot find a valid PCIE lane width!");
}
}
break;
}
}
break;
}
return new_pcie_lanes;
}
#endif