diff options
| author | Timothy Pearson <tpearson@raptorengineeringinc.com> | 2015-06-18 11:48:02 -0500 |
|---|---|---|
| committer | Stefan Reinauer <stefan.reinauer@coreboot.org> | 2015-11-12 00:56:26 +0100 |
| commit | 83b776137399bcfa9427e7a60d5f1620ee2d1985 (patch) | |
| tree | 40638e754b2aa1cbdcd4869ce4fab352dcf611ba | |
| parent | f902722357d5b8a34585c38e9e5c870330f8ccbc (diff) | |
southbridge/amd/sb700: Add option to disable SATA ALPM
The AMD Register Programming Reference states that the user should
have the option to disable Active Link Power Management for two
reasons. First, some drives may not function correctly with the
ALPM implementation of the SP5100, and second there are some
situations where low latency access is more important than the
power savings created by using ALPM.
Allow the user to disable ALPM if desired.
Change-Id: I88055cbb4df4d7ba811cef7056c0a6ca2612fcb0
Signed-off-by: Timothy Pearson <tpearson@raptorengineeringinc.com>
Reviewed-on: http://review.coreboot.org/11993
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
| -rw-r--r-- | src/southbridge/amd/sb700/sata.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/src/southbridge/amd/sb700/sata.c b/src/southbridge/amd/sb700/sata.c index fdf32c780e..c61fa01953 100644 --- a/src/southbridge/amd/sb700/sata.c +++ b/src/southbridge/amd/sb700/sata.c @@ -104,6 +104,7 @@ static void sata_init(struct device *dev) int i, j; uint8_t nvram; uint8_t sata_ahci_mode; + uint8_t sata_alpm_enable; uint8_t port_count; uint8_t max_port_count; @@ -111,6 +112,10 @@ static void sata_init(struct device *dev) if (get_option(&nvram, "sata_ahci_mode") == CB_SUCCESS) sata_ahci_mode = !!nvram; + sata_alpm_enable = 0; + if (get_option(&nvram, "sata_alpm") == CB_SUCCESS) + sata_alpm_enable = !!nvram; + device_t sm_dev; /* SATA SMBus Disable */ sm_dev = dev_find_slot(0, PCI_DEVFN(0x14, 0)); @@ -229,6 +234,13 @@ static void sata_init(struct device *dev) dword &= ~(0x1 << i); write32(sata_bar5 + 0x0c, dword); + /* Disable ALPM if ALPM support not requested */ + if (!sata_alpm_enable) { + dword = read32(sata_bar5 + 0xfc); + dword &= ~(0x1 << 11); /* Disable ALPM */ + write32(sata_bar5 + 0xfc, dword); + } + /* Write protect Sub-Class Code */ byte = pci_read_config8(dev, 0x40); byte &= ~(1 << 0); |