ahci: mcp89: enter AHCI mode under Apple BIOS emulation
Apple's BIOS emulation forcibly disables MCP89 AHCI, eg. on Macbook7,1.
We can re-enable it, replacing the previous workaround of using
ata_generic.
tj: whitespace adjustments, dropped inline from is_mcp89_apple()
Signed-off-by: James Laird <jhl@mafipulation.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index e2903d0..c55e005 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -83,6 +83,8 @@
static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent);
static int ahci_vt8251_hardreset(struct ata_link *link, unsigned int *class,
unsigned long deadline);
+static void ahci_mcp89_apple_enable(struct pci_dev *pdev);
+static bool is_mcp89_apple(struct pci_dev *pdev);
static int ahci_p5wdh_hardreset(struct ata_link *link, unsigned int *class,
unsigned long deadline);
#ifdef CONFIG_PM
@@ -659,6 +661,10 @@
if (rc)
return rc;
+ /* Apple BIOS helpfully mangles the registers on resume */
+ if (is_mcp89_apple(pdev))
+ ahci_mcp89_apple_enable(pdev);
+
if (pdev->dev.power.power_state.event == PM_EVENT_SUSPEND) {
rc = ahci_pci_reset_controller(host);
if (rc)
@@ -775,6 +781,48 @@
}
}
+/*
+ * Macbook7,1 firmware forcibly disables MCP89 AHCI and changes PCI ID when
+ * booting in BIOS compatibility mode. We restore the registers but not ID.
+ */
+static void ahci_mcp89_apple_enable(struct pci_dev *pdev)
+{
+ u32 val;
+
+ printk(KERN_INFO "ahci: enabling MCP89 AHCI mode\n");
+
+ pci_read_config_dword(pdev, 0xf8, &val);
+ val |= 1 << 0x1b;
+ /* the following changes the device ID, but appears not to affect function */
+ /* val = (val & ~0xf0000000) | 0x80000000; */
+ pci_write_config_dword(pdev, 0xf8, val);
+
+ pci_read_config_dword(pdev, 0x54c, &val);
+ val |= 1 << 0xc;
+ pci_write_config_dword(pdev, 0x54c, val);
+
+ pci_read_config_dword(pdev, 0x4a4, &val);
+ val &= 0xff;
+ val |= 0x01060100;
+ pci_write_config_dword(pdev, 0x4a4, val);
+
+ pci_read_config_dword(pdev, 0x54c, &val);
+ val &= ~(1 << 0xc);
+ pci_write_config_dword(pdev, 0x54c, val);
+
+ pci_read_config_dword(pdev, 0xf8, &val);
+ val &= ~(1 << 0x1b);
+ pci_write_config_dword(pdev, 0xf8, val);
+}
+
+static bool is_mcp89_apple(struct pci_dev *pdev)
+{
+ return pdev->vendor == PCI_VENDOR_ID_NVIDIA &&
+ pdev->device == PCI_DEVICE_ID_NVIDIA_NFORCE_MCP89_SATA &&
+ pdev->subsystem_vendor == PCI_VENDOR_ID_APPLE &&
+ pdev->subsystem_device == 0xcb89;
+}
+
/* only some SB600 ahci controllers can do 64bit DMA */
static bool ahci_sb600_enable_64bit(struct pci_dev *pdev)
{
@@ -1207,15 +1255,9 @@
if (pdev->vendor == PCI_VENDOR_ID_MARVELL && !marvell_enable)
return -ENODEV;
- /*
- * For some reason, MCP89 on MacBook 7,1 doesn't work with
- * ahci, use ata_generic instead.
- */
- if (pdev->vendor == PCI_VENDOR_ID_NVIDIA &&
- pdev->device == PCI_DEVICE_ID_NVIDIA_NFORCE_MCP89_SATA &&
- pdev->subsystem_vendor == PCI_VENDOR_ID_APPLE &&
- pdev->subsystem_device == 0xcb89)
- return -ENODEV;
+ /* Apple BIOS on MCP89 prevents us using AHCI */
+ if (is_mcp89_apple(pdev))
+ ahci_mcp89_apple_enable(pdev);
/* Promise's PDC42819 is a SAS/SATA controller that has an AHCI mode.
* At the moment, we can only use the AHCI mode. Let the users know