5.15-stable review patch. If anyone has any objections, please let me know.
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From: Werner Fischer devlists@wefi.net
[ Upstream commit 2a2df98ec592667927b5c1351afa6493ea125c9f ]
Elkhart Lake is the successor of Apollo Lake and Gemini Lake. These CPUs and their PCHs are used in mobile and embedded environments.
With this patch I suggest that Elkhart Lake SATA controllers [1] should use the default LPM policy for mobile chipsets. The disadvantage of missing hot-plug support with this setting should not be an issue, as those CPUs are used in embedded environments and not in servers with hot-plug backplanes.
We discovered that the Elkhart Lake SATA controllers have been missing in ahci.c after a customer reported the throttling of his SATA SSD after a short period of higher I/O. We determined the high temperature of the SSD controller in idle mode as the root cause for that.
Depending on the used SSD, we have seen up to 1.8 Watt lower system idle power usage and up to 30°C lower SSD controller temperatures in our tests, when we set med_power_with_dipm manually. I have provided a table showing seven different SATA SSDs from ATP, Intel/Solidigm and Samsung [2].
Intel lists a total of 3 SATA controller IDs (4B60, 4B62, 4B63) in [1] for those mobile PCHs. This commit just adds 0x4b63 as I do not have test systems with 0x4b60 and 0x4b62 SATA controllers. I have tested this patch with a system which uses 0x4b63 as SATA controller.
[1] https://sata-io.org/product/8803 [2] https://www.thomas-krenn.com/en/wiki/SATA_Link_Power_Management#Example_LES_...
Signed-off-by: Werner Fischer devlists@wefi.net Cc: stable@vger.kernel.org Signed-off-by: Damien Le Moal dlemoal@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/ata/ahci.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c index 3679433108eca..3147b2e6cd8c9 100644 --- a/drivers/ata/ahci.c +++ b/drivers/ata/ahci.c @@ -425,6 +425,8 @@ static const struct pci_device_id ahci_pci_tbl[] = { { PCI_VDEVICE(INTEL, 0x34d3), board_ahci_low_power }, /* Ice Lake LP AHCI */ { PCI_VDEVICE(INTEL, 0x02d3), board_ahci_low_power }, /* Comet Lake PCH-U AHCI */ { PCI_VDEVICE(INTEL, 0x02d7), board_ahci_low_power }, /* Comet Lake PCH RAID */ + /* Elkhart Lake IDs 0x4b60 & 0x4b62 https://sata-io.org/product/8803 not tested yet */ + { PCI_VDEVICE(INTEL, 0x4b63), board_ahci_low_power }, /* Elkhart Lake AHCI */
/* JMicron 360/1/3/5/6, match class to avoid IDE function */ { PCI_VENDOR_ID_JMICRON, PCI_ANY_ID, PCI_ANY_ID, PCI_ANY_ID,