diff options
| author | Kane Chen <kane.chen@intel.com> | 2014-10-01 11:13:54 +0800 |
|---|---|---|
| committer | Stefan Reinauer <stefan.reinauer@coreboot.org> | 2015-03-09 03:33:13 +0100 |
| commit | 18cb1340f185150b9708257ba8024b6900706083 (patch) | |
| tree | 0d567633540e19104711d664b44f144ba653ec25 /src/device | |
| parent | 2c4aab3fd6cd7b357b8389c20a95a6ad59cc75a0 (diff) | |
device/pciexp: Add support for PCIe CLK power management
Set PCIe "Enable Clock Power Management", if endpoint supports it.
BUG=chrome-os-partner:31424
BRANCH=none
TEST=build and boot on rambi, check Enable Clock Power Management
in link control register is set properly
Change-Id: Ie54110d1ef42184cfcf47c9fe4d735960aebe47f
Signed-off-by: Kane Chen <kane.chen@intel.com>
Reviewed-on: https://chromium-review.googlesource.com/220742
Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
[Edit commit message.]
Signed-off-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-on: http://review.coreboot.org/8447
Tested-by: build bot (Jenkins)
Reviewed-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
Diffstat (limited to 'src/device')
| -rw-r--r-- | src/device/Kconfig | 8 | ||||
| -rw-r--r-- | src/device/pciexp_device.c | 22 |
2 files changed, 30 insertions, 0 deletions
diff --git a/src/device/Kconfig b/src/device/Kconfig index 91da02a193..42a68d296a 100644 --- a/src/device/Kconfig +++ b/src/device/Kconfig @@ -251,6 +251,14 @@ config PCIEXP_ASPM help Detect and enable ASPM on PCIe links. +config PCIEXP_CLK_PM + prompt "Enable PCIe Clock Power Management" + bool + depends on PCIEXP_PLUGIN_SUPPORT + default n + help + Detect and enable Clock Power Management on PCIe. + config PCI_BUS_SEGN_BITS int default 0 diff --git a/src/device/pciexp_device.c b/src/device/pciexp_device.c index 87aea672db..edb103d861 100644 --- a/src/device/pciexp_device.c +++ b/src/device/pciexp_device.c @@ -90,6 +90,23 @@ static void pciexp_enable_common_clock(device_t root, unsigned root_cap, } #endif /* CONFIG_PCIEXP_COMMON_CLOCK */ +#if CONFIG_PCIEXP_CLK_PM +static void pciexp_enable_clock_power_pm(device_t endp, unsigned endp_cap) +{ + /* check if per port clk req is supported in device */ + u32 endp_ca; + u16 lnkctl; + endp_ca = pci_read_config32(endp, endp_cap + PCI_EXP_LNKCAP); + if ((endp_ca & PCI_EXP_CLK_PM) == 0) { + printk(BIOS_INFO, "PCIE CLK PM is not supported by endpoint"); + return; + } + lnkctl = pci_read_config16(endp, endp_cap + PCI_EXP_LNKCTL); + lnkctl = lnkctl | PCI_EXP_EN_CLK_PM; + pci_write_config16(endp, endp_cap + PCI_EXP_LNKCTL, lnkctl); +} +#endif /* CONFIG_PCIEXP_CLK_PM */ + #if CONFIG_PCIEXP_ASPM /* * Determine the ASPM L0s or L1 exit latency for a link @@ -200,6 +217,11 @@ static void pciexp_tune_dev(device_t dev) pciexp_enable_common_clock(root, root_cap, dev, cap); #endif +#if CONFIG_PCIEXP_CLK_PM + /* Check if per port CLK req is supported by endpoint*/ + pciexp_enable_clock_power_pm(dev, cap); +#endif + #if CONFIG_PCIEXP_ASPM /* Check for and enable ASPM */ enum aspm_type apmc = pciexp_enable_aspm(root, root_cap, dev, cap); |