Commit a48f3d5b authored by Bjorn Helgaas's avatar Bjorn Helgaas
Browse files

PCI/ASPM: Add L1 Substates definitions 



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: default avatarBjorn Helgaas <bhelgaas@google.com>
Reviewed-by: default avatarVidya Sagar <vidyas@nvidia.com>
parent 7f88ba4a

drivers/pci/pcie/aspm.c

+20 −14
Original line number Diff line number Diff line
@@ -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;

include/uapi/linux/pci_regs.h

+6 −0
Original line number Diff line number Diff line
@@ -1002,12 +1002,18 @@ 
#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 */