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| author | Tejun Heo <htejun@gmail.com> | 2008-04-23 20:52:58 +0900 |
|---|---|---|
| committer | Jeff Garzik <jgarzik@redhat.com> | 2008-04-25 00:45:13 -0400 |
| commit | 15fe982e429e0e6b7466719acb6cfd9dbfe47f0c (patch) | |
| tree | de5ac9b692257050bf8dbdb6ebe02e780fddad46 /drivers/ata/ahci.c | |
| parent | 411cb3869afd91ed40e8f12df64cd9e315356305 (diff) | |
| download | kernel_samsung_smdk4412-15fe982e429e0e6b7466719acb6cfd9dbfe47f0c.zip kernel_samsung_smdk4412-15fe982e429e0e6b7466719acb6cfd9dbfe47f0c.tar.gz kernel_samsung_smdk4412-15fe982e429e0e6b7466719acb6cfd9dbfe47f0c.tar.bz2 | |
ahci: retry enabling AHCI a few times before spitting out WARN_ON()
Some chips need AHCI_EN set more than once to actually set it. Try a
few times before giving up and spitting out WARN_ON().
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Peer Chen <pchen@nvidia.com>
Cc: Volker Armin Hemmann <volker.armin.hemmann@tu-clausthal.de>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Diffstat (limited to 'drivers/ata/ahci.c')
| -rw-r--r-- | drivers/ata/ahci.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c index 986e332..7c4f886 100644 --- a/drivers/ata/ahci.c +++ b/drivers/ata/ahci.c @@ -556,16 +556,27 @@ static inline void __iomem *ahci_port_base(struct ata_port *ap) static void ahci_enable_ahci(void __iomem *mmio) { + int i; u32 tmp; /* turn on AHCI_EN */ tmp = readl(mmio + HOST_CTL); - if (!(tmp & HOST_AHCI_EN)) { + if (tmp & HOST_AHCI_EN) + return; + + /* Some controllers need AHCI_EN to be written multiple times. + * Try a few times before giving up. + */ + for (i = 0; i < 5; i++) { tmp |= HOST_AHCI_EN; writel(tmp, mmio + HOST_CTL); tmp = readl(mmio + HOST_CTL); /* flush && sanity check */ - WARN_ON(!(tmp & HOST_AHCI_EN)); + if (tmp & HOST_AHCI_EN) + return; + msleep(10); } + + WARN_ON(1); } /** |