diff options
Diffstat (limited to 'drivers/ata')
| -rw-r--r-- | drivers/ata/ahci.c | 95 |
1 files changed, 72 insertions, 23 deletions
diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c index fd27227771b..c31b6636632 100644 --- a/drivers/ata/ahci.c +++ b/drivers/ata/ahci.c @@ -188,8 +188,10 @@ struct ahci_sg { }; struct ahci_host_priv { - u32 cap; /* cache of HOST_CAP register */ - u32 port_map; /* cache of HOST_PORTS_IMPL reg */ + u32 cap; /* cap to use */ + u32 port_map; /* port map to use */ + u32 saved_cap; /* saved initial cap */ + u32 saved_port_map; /* saved initial port_map */ }; struct ahci_port_priv { @@ -477,6 +479,65 @@ static inline void __iomem *ahci_port_base(void __iomem *base, return base + 0x100 + (port * 0x80); } +/** + * ahci_save_initial_config - Save and fixup initial config values + * @probe_ent: probe_ent of target device + * + * Some registers containing configuration info might be setup by + * BIOS and might be cleared on reset. This function saves the + * initial values of those registers into @hpriv such that they + * can be restored after controller reset. + * + * If inconsistent, config values are fixed up by this function. + * + * LOCKING: + * None. + */ +static void ahci_save_initial_config(struct ata_probe_ent *probe_ent) +{ + struct ahci_host_priv *hpriv = probe_ent->private_data; + void __iomem *mmio = probe_ent->iomap[AHCI_PCI_BAR]; + u32 cap, port_map; + + /* Values prefixed with saved_ are written back to host after + * reset. Values without are used for driver operation. + */ + hpriv->saved_cap = cap = readl(mmio + HOST_CAP); + hpriv->saved_port_map = port_map = readl(mmio + HOST_PORTS_IMPL); + + /* fixup zero port_map */ + if (!port_map) { + port_map = (1 << ahci_nr_ports(hpriv->cap)) - 1; + dev_printk(KERN_WARNING, probe_ent->dev, + "PORTS_IMPL is zero, forcing 0x%x\n", port_map); + + /* write the fixed up value to the PI register */ + hpriv->saved_port_map = port_map; + } + + /* record values to use during operation */ + hpriv->cap = cap; + hpriv->port_map = port_map; +} + +/** + * ahci_restore_initial_config - Restore initial config + * @mmio: MMIO base for the host + * @hpriv: host private data + * + * Restore initial config stored by ahci_save_initial_config(). + * + * LOCKING: + * None. + */ +static void ahci_restore_initial_config(void __iomem *mmio, + struct ahci_host_priv *hpriv) +{ + writel(hpriv->saved_cap, mmio + HOST_CAP); + writel(hpriv->saved_port_map, mmio + HOST_PORTS_IMPL); + (void) readl(mmio + HOST_PORTS_IMPL); /* flush */ +} + static u32 ahci_scr_read (struct ata_port *ap, unsigned int sc_reg_in) { unsigned int sc_reg; @@ -653,12 +714,10 @@ static int ahci_deinit_port(void __iomem *port_mmio, u32 cap, const char **emsg) return 0; } -static int ahci_reset_controller(void __iomem *mmio, struct pci_dev *pdev) +static int ahci_reset_controller(void __iomem *mmio, struct pci_dev *pdev, + struct ahci_host_priv *hpriv) { - u32 cap_save, impl_save, tmp; - - cap_save = readl(mmio + HOST_CAP); - impl_save = readl(mmio + HOST_PORTS_IMPL); + u32 tmp; /* global controller reset */ tmp = readl(mmio + HOST_CTL); @@ -683,18 +742,8 @@ static int ahci_reset_controller(void __iomem *mmio, struct pci_dev *pdev) writel(HOST_AHCI_EN, mmio + HOST_CTL); (void) readl(mmio + HOST_CTL); /* flush */ - /* These write-once registers are normally cleared on reset. - * Restore BIOS values... which we HOPE were present before - * reset. - */ - if (!impl_save) { - impl_save = (1 << ahci_nr_ports(cap_save)) - 1; - dev_printk(KERN_WARNING, &pdev->dev, - "PORTS_IMPL is zero, forcing 0x%x\n", impl_save); - } - writel(cap_save, mmio + HOST_CAP); - writel(impl_save, mmio + HOST_PORTS_IMPL); - (void) readl(mmio + HOST_PORTS_IMPL); /* flush */ + /* some registers might be cleared on reset. restore initial values */ + ahci_restore_initial_config(mmio, hpriv); if (pdev->vendor == PCI_VENDOR_ID_INTEL) { u16 tmp16; @@ -1432,7 +1481,7 @@ static int ahci_pci_device_resume(struct pci_dev *pdev) return rc; if (pdev->dev.power.power_state.event == PM_EVENT_SUSPEND) { - rc = ahci_reset_controller(mmio, pdev); + rc = ahci_reset_controller(mmio, pdev, hpriv); if (rc) return rc; @@ -1543,12 +1592,10 @@ static int ahci_host_init(struct ata_probe_ent *probe_ent) unsigned int i, cap_n_ports, using_dac; int rc; - rc = ahci_reset_controller(mmio, pdev); + rc = ahci_reset_controller(mmio, pdev, hpriv); if (rc) return rc; - hpriv->cap = readl(mmio + HOST_CAP); - hpriv->port_map = readl(mmio + HOST_PORTS_IMPL); cap_n_ports = ahci_nr_ports(hpriv->cap); VPRINTK("cap 0x%x port_map 0x%x n_ports %d\n", @@ -1739,6 +1786,8 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent) probe_ent->private_data = hpriv; /* initialize adapter */ + ahci_save_initial_config(probe_ent); + rc = ahci_host_init(probe_ent); if (rc) return rc; |