The patch titled pm: ahci: speed up resume has been added to the -mm tree. Its filename is pm-ahci-speed-up-resume.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find out what to do about this The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/ ------------------------------------------------------ Subject: pm: ahci: speed up resume From: Zhang Rui <rui.zhang@xxxxxxxxx> During resume, sleep 1 second to wait for the HBA reset to finish is a waste of time. According to the AHCI 1.2 spec, We should poll the HOST_CTL register, and return error if the host reset is not finished within 1 second. Test results show that the HBA reset can be done quickly(in usecs). And this patch may save nearly 1 second during resume. Signed-off-by: Zhang Rui <rui.zhang@xxxxxxxxx> Acked-by: Tejun Heo <tj@xxxxxxxxxx> Signed-off-by: Rafael J. Wysocki <rjw@xxxxxxx> Cc: Jeff Garzik <jeff@xxxxxxxxxx> Acked-by: Pavel Machek <pavel@xxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- drivers/ata/ahci.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff -puN drivers/ata/ahci.c~pm-ahci-speed-up-resume drivers/ata/ahci.c --- a/drivers/ata/ahci.c~pm-ahci-speed-up-resume +++ a/drivers/ata/ahci.c @@ -1142,12 +1142,15 @@ static int ahci_reset_controller(struct readl(mmio + HOST_CTL); /* flush */ } - /* reset must complete within 1 second, or + /* + * to perform host reset, OS should set HOST_RESET + * and poll until this bit is read to be "0". + * reset must complete within 1 second, or * the hardware should be considered fried. */ - ssleep(1); + tmp = ata_wait_register(mmio + HOST_CTL, HOST_RESET, + HOST_RESET, 10, 1000); - tmp = readl(mmio + HOST_CTL); if (tmp & HOST_RESET) { dev_printk(KERN_ERR, host->dev, "controller reset failed (0x%x)\n", tmp); _ Patches currently in -mm which might be from rui.zhang@xxxxxxxxx are linux-next.patch pm-ahci-speed-up-resume.patch pm-introduce-new-interfaces-schedule_work_on-and-queue_work_on.patch pm-schedule-sysrq-poweroff-on-boot-cpu.patch dcdbas-use-memory_read_from_buffer.patch dell_rbu-use-memory_read_from_buffer.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html