drm/radeon/kms: add pcie get/set lane support for r6xx/r7xx/evergreen

Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 118 insertions, 0 deletions

diff --git a/drivers/gpu/drm/radeon/r600.c b/drivers/gpu/drm/radeon/r600.c
index 279794c391e9..60ad8c03081a 100644
--- a/drivers/gpu/drm/radeon/r600.c
+++ b/drivers/gpu/drm/radeon/r600.c
@@ -3531,3 +3531,121 @@ void r600_ioctl_wait_idle(struct radeon_device *rdev, struct radeon_bo *bo)
         } else
                 WREG32(R_005480_HDP_MEM_COHERENCY_FLUSH_CNTL, 0x1);
 }
+
+void r600_set_pcie_lanes(struct radeon_device *rdev, int lanes)
+{
+        u32 link_width_cntl, mask, target_reg;
+
+        if (rdev->flags & RADEON_IS_IGP)
+                return;
+
+        if (!(rdev->flags & RADEON_IS_PCIE))
+                return;
+
+        /* x2 cards have a special sequence */
+        if (ASIC_IS_X2(rdev))
+                return;
+
+        /* FIXME wait for idle */
+
+        switch (lanes) {
+        case 0:
+                mask = RADEON_PCIE_LC_LINK_WIDTH_X0;
+                break;
+        case 1:
+                mask = RADEON_PCIE_LC_LINK_WIDTH_X1;
+                break;
+        case 2:
+                mask = RADEON_PCIE_LC_LINK_WIDTH_X2;
+                break;
+        case 4:
+                mask = RADEON_PCIE_LC_LINK_WIDTH_X4;
+                break;
+        case 8:
+                mask = RADEON_PCIE_LC_LINK_WIDTH_X8;
+                break;
+        case 12:
+                mask = RADEON_PCIE_LC_LINK_WIDTH_X12;
+                break;
+        case 16:
+        default:
+                mask = RADEON_PCIE_LC_LINK_WIDTH_X16;
+                break;
+        }
+
+        link_width_cntl = RREG32_PCIE_P(RADEON_PCIE_LC_LINK_WIDTH_CNTL);
+
+        if ((link_width_cntl & RADEON_PCIE_LC_LINK_WIDTH_RD_MASK) ==
+            (mask << RADEON_PCIE_LC_LINK_WIDTH_RD_SHIFT))
+                return;
+
+        if (link_width_cntl & R600_PCIE_LC_UPCONFIGURE_DIS)
+                return;
+
+        link_width_cntl &= ~(RADEON_PCIE_LC_LINK_WIDTH_MASK |
+                             RADEON_PCIE_LC_RECONFIG_NOW |
+                             R600_PCIE_LC_RENEGOTIATE_EN |
+                             R600_PCIE_LC_RECONFIG_ARC_MISSING_ESCAPE);
+        link_width_cntl |= mask;
+
+        WREG32_PCIE_P(RADEON_PCIE_LC_LINK_WIDTH_CNTL, link_width_cntl);
+
+        /* some northbridges can renegotiate the link rather than requiring                                  
+         * a complete re-config.                                                                             
+         * e.g., AMD 780/790 northbridges (pci ids: 0x5956, 0x5957, 0x5958, etc.)                            
+         */
+        if (link_width_cntl & R600_PCIE_LC_RENEGOTIATION_SUPPORT)
+                link_width_cntl |= R600_PCIE_LC_RENEGOTIATE_EN | R600_PCIE_LC_UPCONFIGURE_SUPPORT;
+        else
+                link_width_cntl |= R600_PCIE_LC_RECONFIG_ARC_MISSING_ESCAPE;
+
+        WREG32_PCIE_P(RADEON_PCIE_LC_LINK_WIDTH_CNTL, (link_width_cntl |
+                                                       RADEON_PCIE_LC_RECONFIG_NOW));
+
+        if (rdev->family >= CHIP_RV770)
+                target_reg = R700_TARGET_AND_CURRENT_PROFILE_INDEX;
+        else
+                target_reg = R600_TARGET_AND_CURRENT_PROFILE_INDEX;
+
+        /* wait for lane set to complete */
+        link_width_cntl = RREG32(target_reg);
+        while (link_width_cntl == 0xffffffff)
+                link_width_cntl = RREG32(target_reg);
+
+}
+
+int r600_get_pcie_lanes(struct radeon_device *rdev)
+{
+        u32 link_width_cntl;
+
+        if (rdev->flags & RADEON_IS_IGP)
+                return 0;
+
+        if (!(rdev->flags & RADEON_IS_PCIE))
+                return 0;
+
+        /* x2 cards have a special sequence */
+        if (ASIC_IS_X2(rdev))
+                return 0;
+
+        /* FIXME wait for idle */
+
+        link_width_cntl = RREG32_PCIE_P(RADEON_PCIE_LC_LINK_WIDTH_CNTL);
+
+        switch ((link_width_cntl & RADEON_PCIE_LC_LINK_WIDTH_RD_MASK) >> RADEON_PCIE_LC_LINK_WIDTH_RD_SHIFT) {
+        case RADEON_PCIE_LC_LINK_WIDTH_X0:
+                return 0;
+        case RADEON_PCIE_LC_LINK_WIDTH_X1:
+                return 1;
+        case RADEON_PCIE_LC_LINK_WIDTH_X2:
+                return 2;
+        case RADEON_PCIE_LC_LINK_WIDTH_X4:
+                return 4;
+        case RADEON_PCIE_LC_LINK_WIDTH_X8:
+                return 8;
+        case RADEON_PCIE_LC_LINK_WIDTH_X16:
+        default:
+                return 16;
+        }
+}
+