PCI/ASPM: Add L1 Substates definitions
authorBjorn Helgaas <bhelgaas@google.com>
Mon, 13 Nov 2017 14:36:40 +0000 (08:36 -0600)
committerBjorn Helgaas <bhelgaas@google.com>
Tue, 14 Nov 2017 14:32:47 +0000 (08:32 -0600)
Add and use #defines for L1 Substate register fields instead of hard-coding
the masks.  Also update comments to use names from the spec.  No functional
change intended.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Vidya Sagar <vidyas@nvidia.com>
drivers/pci/pcie/aspm.c
include/uapi/linux/pci_regs.h

index a378dd9d2473a07314af283f04247fb5354e404d..d240ffab24c1326eaa7e44f054682ed881fafe26 100644 (file)
@@ -450,24 +450,25 @@ static void aspm_calc_l1ss_info(struct pcie_link_state *link,
        if (!(link->aspm_support & ASPM_STATE_L1_2_MASK))
                return;
 
-       /* Choose the greater of the two T_cmn_mode_rstr_time */
-       val1 = (upreg->l1ss_cap >> 8) & 0xFF;
-       val2 = (dwreg->l1ss_cap >> 8) & 0xFF;
+       /* Choose the greater of the two Port Common_Mode_Restore_Times */
+       val1 = (upreg->l1ss_cap & PCI_L1SS_CAP_CM_RESTORE_TIME) >> 8;
+       val2 = (dwreg->l1ss_cap & PCI_L1SS_CAP_CM_RESTORE_TIME) >> 8;
        if (val1 > val2)
                link->l1ss.ctl1 |= val1 << 8;
        else
                link->l1ss.ctl1 |= val2 << 8;
+
        /*
         * We currently use LTR L1.2 threshold to be fixed constant picked from
         * Intel's coreboot.
         */
        link->l1ss.ctl1 |= LTR_L1_2_THRESHOLD_BITS;
 
-       /* Choose the greater of the two T_pwr_on */
-       val1 = (upreg->l1ss_cap >> 19) & 0x1F;
-       scale1 = (upreg->l1ss_cap >> 16) & 0x03;
-       val2 = (dwreg->l1ss_cap >> 19) & 0x1F;
-       scale2 = (dwreg->l1ss_cap >> 16) & 0x03;
+       /* Choose the greater of the two Port T_POWER_ON times */
+       val1   = (upreg->l1ss_cap & PCI_L1SS_CAP_P_PWR_ON_VALUE) >> 19;
+       scale1 = (upreg->l1ss_cap & PCI_L1SS_CAP_P_PWR_ON_SCALE) >> 16;
+       val2   = (dwreg->l1ss_cap & PCI_L1SS_CAP_P_PWR_ON_VALUE) >> 19;
+       scale2 = (dwreg->l1ss_cap & PCI_L1SS_CAP_P_PWR_ON_SCALE) >> 16;
 
        if (calc_l1ss_pwron(link->pdev, scale1, val1) >
            calc_l1ss_pwron(link->downstream, scale2, val2))
@@ -646,21 +647,26 @@ static void pcie_config_aspm_l1ss(struct pcie_link_state *link, u32 state)
 
        if (enable_req & ASPM_STATE_L1_2_MASK) {
 
-               /* Program T_pwr_on in both ports */
+               /* Program T_POWER_ON times in both ports */
                pci_write_config_dword(parent, up_cap_ptr + PCI_L1SS_CTL2,
                                       link->l1ss.ctl2);
                pci_write_config_dword(child, dw_cap_ptr + PCI_L1SS_CTL2,
                                       link->l1ss.ctl2);
 
-               /* Program T_cmn_mode in parent */
+               /* Program Common_Mode_Restore_Time in upstream device */
                pci_clear_and_set_dword(parent, up_cap_ptr + PCI_L1SS_CTL1,
-                                       0xFF00, link->l1ss.ctl1);
+                                       PCI_L1SS_CTL1_CM_RESTORE_TIME,
+                                       link->l1ss.ctl1);
 
-               /* Program LTR L1.2 threshold in both ports */
+               /* Program LTR_L1.2_THRESHOLD time in both ports */
                pci_clear_and_set_dword(parent, up_cap_ptr + PCI_L1SS_CTL1,
-                                       0xE3FF0000, link->l1ss.ctl1);
+                                       PCI_L1SS_CTL1_LTR_L12_TH_VALUE |
+                                       PCI_L1SS_CTL1_LTR_L12_TH_SCALE,
+                                       link->l1ss.ctl1);
                pci_clear_and_set_dword(child, dw_cap_ptr + PCI_L1SS_CTL1,
-                                       0xE3FF0000, link->l1ss.ctl1);
+                                       PCI_L1SS_CTL1_LTR_L12_TH_VALUE |
+                                       PCI_L1SS_CTL1_LTR_L12_TH_SCALE,
+                                       link->l1ss.ctl1);
        }
 
        val = 0;
index 4150acb4cccbd303637a458e28785b9039e12472..85a4014de42ee83ac94ebd44c8e07d629d469bc0 100644 (file)
 #define  PCI_L1SS_CAP_ASPM_L1_2                0x00000004  /* ASPM L1.2 Supported */
 #define  PCI_L1SS_CAP_ASPM_L1_1                0x00000008  /* ASPM L1.1 Supported */
 #define  PCI_L1SS_CAP_L1_PM_SS         0x00000010  /* L1 PM Substates Supported */
+#define  PCI_L1SS_CAP_CM_RESTORE_TIME  0x0000ff00  /* Port Common_Mode_Restore_Time */
+#define  PCI_L1SS_CAP_P_PWR_ON_SCALE   0x00030000  /* Port T_POWER_ON scale */
+#define  PCI_L1SS_CAP_P_PWR_ON_VALUE   0x00f80000  /* Port T_POWER_ON value */
 #define PCI_L1SS_CTL1          0x08    /* Control 1 Register */
 #define  PCI_L1SS_CTL1_PCIPM_L1_2      0x00000001  /* PCI-PM L1.2 Enable */
 #define  PCI_L1SS_CTL1_PCIPM_L1_1      0x00000002  /* PCI-PM L1.1 Enable */
 #define  PCI_L1SS_CTL1_ASPM_L1_2       0x00000004  /* ASPM L1.2 Enable */
 #define  PCI_L1SS_CTL1_ASPM_L1_1       0x00000008  /* ASPM L1.1 Enable */
 #define  PCI_L1SS_CTL1_L1SS_MASK       0x0000000f
+#define  PCI_L1SS_CTL1_CM_RESTORE_TIME 0x0000ff00  /* Common_Mode_Restore_Time */
+#define  PCI_L1SS_CTL1_LTR_L12_TH_VALUE        0x03ff0000  /* LTR_L1.2_THRESHOLD_Value */
+#define  PCI_L1SS_CTL1_LTR_L12_TH_SCALE        0xe0000000  /* LTR_L1.2_THRESHOLD_Scale */
 #define PCI_L1SS_CTL2          0x0c    /* Control 2 Register */
 
 #endif /* LINUX_PCI_REGS_H */