sky2: pci power savings

Turn on special bits to save more power when device is shutdown.
Tested on a limited range of hardware, some of the bits are for hardware
that probably isn't even in production (like Yukon Supreme) and was ported
from the vendor driver.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

1 files changed, 92 insertions, 6 deletions

diff --git a/drivers/net/sky2.c b/drivers/net/sky2.c
index 59cb9cd00ad2..c83406f4f2a7 100644
--- a/drivers/net/sky2.c
+++ b/drivers/net/sky2.c
@@ -284,6 +284,86 @@ static void sky2_power_aux(struct sky2_hw *hw)
                              PC_VAUX_ON | PC_VCC_OFF));
 }
 
+static void sky2_power_state(struct sky2_hw *hw, pci_power_t state)
+{
+        u16 power_control = sky2_pci_read16(hw, hw->pm_cap + PCI_PM_CTRL);
+        int pex = pci_find_capability(hw->pdev, PCI_CAP_ID_EXP);
+        u32 reg;
+
+        sky2_write8(hw, B2_TST_CTRL1, TST_CFG_WRITE_ON);
+
+        switch (state) {
+        case PCI_D0:
+                break;
+
+        case PCI_D1:
+                power_control |= 1;
+                break;
+
+        case PCI_D2:
+                power_control |= 2;
+                break;
+
+        case PCI_D3hot:
+        case PCI_D3cold:
+                power_control |= 3;
+                if (hw->flags & SKY2_HW_ADV_POWER_CTL) {
+                        /* additional power saving measurements */
+                        reg = sky2_pci_read32(hw, PCI_DEV_REG4);
+
+                        /* set gating core clock for LTSSM in L1 state */
+                        reg |= P_PEX_LTSSM_STAT(P_PEX_LTSSM_L1_STAT) |
+                                /* auto clock gated scheme controlled by CLKREQ */
+                                P_ASPM_A1_MODE_SELECT |
+                                /* enable Gate Root Core Clock */
+                                P_CLK_GATE_ROOT_COR_ENA;
+
+                        if (pex && (hw->flags & SKY2_HW_CLK_POWER)) {
+                                /* enable Clock Power Management (CLKREQ) */
+                                u16 ctrl = sky2_pci_read16(hw, pex + PCI_EXP_DEVCTL);
+
+                                ctrl |= PCI_EXP_DEVCTL_AUX_PME;
+                                sky2_pci_write16(hw, pex + PCI_EXP_DEVCTL, ctrl);
+                        } else
+                                /* force CLKREQ Enable in Our4 (A1b only) */
+                                reg |= P_ASPM_FORCE_CLKREQ_ENA;
+
+                        /* set Mask Register for Release/Gate Clock */
+                        sky2_pci_write32(hw, PCI_DEV_REG5,
+                                         P_REL_PCIE_EXIT_L1_ST | P_GAT_PCIE_ENTER_L1_ST |
+                                         P_REL_PCIE_RX_EX_IDLE | P_GAT_PCIE_RX_EL_IDLE |
+                                         P_REL_GPHY_LINK_UP | P_GAT_GPHY_LINK_DOWN);
+                } else
+                        sky2_write8(hw, B28_Y2_ASF_STAT_CMD, Y2_ASF_CLK_HALT);
+
+                /* put CPU into reset state */
+                sky2_write8(hw,  B28_Y2_ASF_STAT_CMD, HCU_CCSR_ASF_RESET);
+                if (hw->chip_id == CHIP_ID_YUKON_SUPR && hw->chip_rev == CHIP_REV_YU_SU_A0)
+                        /* put CPU into halt state */
+                        sky2_write8(hw, B28_Y2_ASF_STAT_CMD, HCU_CCSR_ASF_HALTED);
+
+                if (pex && !(hw->flags & SKY2_HW_RAM_BUFFER)) {
+                        reg = sky2_pci_read32(hw, PCI_DEV_REG1);
+                        /* force to PCIe L1 */
+                        reg |= PCI_FORCE_PEX_L1;
+                        sky2_pci_write32(hw, PCI_DEV_REG1, reg);
+                }
+                break;
+
+        default:
+                dev_warn(&hw->pdev->dev, PFX "Invalid power state (%d) ",
+                       state);
+                return;
+        }
+
+        power_control |= PCI_PM_CTRL_PME_ENABLE;
+        /* Finally, set the new power state. */
+        sky2_pci_write32(hw, hw->pm_cap + PCI_PM_CTRL, power_control);
+
+        sky2_write8(hw, B2_TST_CTRL1, TST_CFG_WRITE_OFF);
+        sky2_pci_read32(hw, B0_CTST);
+}
+
 static void sky2_gmac_reset(struct sky2_hw *hw, unsigned port)
 {
         u16 reg;
@@ -2786,6 +2866,10 @@ static int __devinit sky2_init(struct sky2_hw *hw)
                 hw->flags = SKY2_HW_GIGABIT
                         | SKY2_HW_NEWER_PHY
                         | SKY2_HW_ADV_POWER_CTL;
+
+                /* check for Rev. A1 dev 4200 */
+                if (sky2_read16(hw, Q_ADDR(Q_XA1, Q_WM)) == 0)
+                        hw->flags |= SKY2_HW_CLK_POWER;
                 break;
 
         case CHIP_ID_YUKON_EX:
@@ -2836,6 +2920,11 @@ static int __devinit sky2_init(struct sky2_hw *hw)
         if (hw->pmd_type == 'L' || hw->pmd_type == 'S' || hw->pmd_type == 'P')
                 hw->flags |= SKY2_HW_FIBRE_PHY;
 
+        hw->pm_cap = pci_find_capability(hw->pdev, PCI_CAP_ID_PM);
+        if (hw->pm_cap == 0) {
+                dev_err(&hw->pdev->dev, "cannot find PowerManagement capability\n");
+                return -EIO;
+        }
 
         hw->ports = 1;
         t8 = sky2_read8(hw, B2_Y2_HW_RES);
@@ -4407,7 +4496,7 @@ static int sky2_suspend(struct pci_dev *pdev, pm_message_t state)
 
         pci_save_state(pdev);
         pci_enable_wake(pdev, pci_choose_state(pdev, state), wol);
-        pci_set_power_state(pdev, pci_choose_state(pdev, state));
+        sky2_power_state(hw, pci_choose_state(pdev, state));
 
         return 0;
 }
@@ -4420,9 +4509,7 @@ static int sky2_resume(struct pci_dev *pdev)
         if (!hw)
                 return 0;
 
-        err = pci_set_power_state(pdev, PCI_D0);
-        if (err)
-                goto out;
+        sky2_power_state(hw, PCI_D0);
 
         err = pci_restore_state(pdev);
         if (err)
@@ -4490,8 +4577,7 @@ static void sky2_shutdown(struct pci_dev *pdev)
         pci_enable_wake(pdev, PCI_D3cold, wol);
 
         pci_disable_device(pdev);
-        pci_set_power_state(pdev, PCI_D3hot);
-
+        sky2_power_state(hw, PCI_D3hot);
 }
 
 static struct pci_driver sky2_driver = {