drm/amdgpu: extract pcie helpers to common header

These will be used by multiple powerplay drivers and
other IP modules.

Reviewed-by: Jammy Zhou <Jammy.Zhou@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 141 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/include/amd_pcie_helpers.h b/drivers/gpu/drm/amd/include/amd_pcie_helpers.h
new file mode 100644
index 000000000000..2cfdf054953b
--- /dev/null
+++ b/drivers/gpu/drm/amd/include/amd_pcie_helpers.h
@@ -0,0 +1,141 @@
+/*
+ * 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 1;
+
+	return 0;
+}
+
+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 1;
+
+	return 0;
+}
+
+/* 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