From 4c1e9aa41b2f9afe8f26e2efe5bb4695f6c40772 Mon Sep 17 00:00:00 2001 From: David Milburn Date: Fri, 3 Apr 2009 15:36:41 -0500 Subject: libata: ahci enclosure management bios workaround References: bnc#489005 During driver initialization ahci_start_port may not be able to turn LEDs off because the hardware may still be transmitting a message. And since the BIOS may not be setting the LEDs to off the drive LEDs may end up in a fault state. This has been seen on ICH9r and ICH10r when configured in AHCI mode instead of RAID mode, this patch doesn't key off a specific set of device IDs but will give the EM transmit bit a chance to clear if busy. Signed-off-by: David Milburn Signed-off-by: Jeff Garzik Signed-off-by: Tejun Heo --- drivers/ata/ahci.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) Index: linux-2.6.27-SLE11_BRANCH/drivers/ata/ahci.c =================================================================== --- linux-2.6.27-SLE11_BRANCH.orig/drivers/ata/ahci.c +++ linux-2.6.27-SLE11_BRANCH/drivers/ata/ahci.c @@ -62,6 +62,7 @@ static ssize_t ahci_led_store(struct ata static ssize_t ahci_transmit_led_message(struct ata_port *ap, u32 state, ssize_t size); #define MAX_SLOTS 8 +#define MAX_RETRY 15 enum { AHCI_PCI_BAR = 5, @@ -1095,6 +1096,8 @@ static void ahci_start_port(struct ata_p struct ahci_port_priv *pp = ap->private_data; struct ata_link *link; struct ahci_em_priv *emp; + ssize_t rc; + int i; /* enable FIS reception */ ahci_start_fis_rx(ap); @@ -1106,7 +1109,17 @@ static void ahci_start_port(struct ata_p if (ap->flags & ATA_FLAG_EM) { ata_port_for_each_link(link, ap) { emp = &pp->em_priv[link->pmp]; - ahci_transmit_led_message(ap, emp->led_state, 4); + + /* EM Transmit bit maybe busy during init */ + for (i = 0; i < MAX_RETRY; i++) { + rc = ahci_transmit_led_message(ap, + emp->led_state, + 4); + if (rc == -EBUSY) + udelay(100); + else + break; + } } } @@ -1308,7 +1321,7 @@ static ssize_t ahci_transmit_led_message em_ctl = readl(mmio + HOST_EM_CTL); if (em_ctl & EM_CTL_TM) { spin_unlock_irqrestore(ap->lock, flags); - return -EINVAL; + return -EBUSY; } /*