@@ -416,13 +416,22 @@ struct amd_iommu {
struct dma_ops_domain *default_dom;
/*
- * This array is required to work around a potential BIOS bug.
- * The BIOS may miss to restore parts of the PCI configuration
- * space when the system resumes from S3. The result is that the
- * IOMMU does not execute commands anymore which leads to system
- * failure.
+ * We can't rely on the BIOS to restore all values on reinit, so we
+ * need to stash them
*/
- u32 cache_cfg[4];
+
+ /* The iommu BAR */
+ u32 stored_addr_lo;
+ u32 stored_addr_hi;
+
+ /*
+ * Each iommu has 6 l1s, each of which is documented as having 0x12
+ * registers
+ */
+ u32 stored_l1[6][0x12];
+
+ /* The l2 indirect registers */
+ u32 stored_l2[0x83];
};
/*
@@ -194,6 +194,39 @@ static inline unsigned long tbl_size(int entry_size)
return 1UL << shift;
}
+/* Access to l1 and l2 indexed register spaces */
+
+static u32 iommu_read_l1(struct amd_iommu *iommu, u16 l1, u8 address)
+{
+ u32 val;
+
+ pci_write_config_dword(iommu->dev, 0xf8, (address | l1 << 16));
+ pci_read_config_dword(iommu->dev, 0xfc, &val);
+ return val;
+}
+
+static void iommu_write_l1(struct amd_iommu *iommu, u16 l1, u8 address, u32 val)
+{
+ pci_write_config_dword(iommu->dev, 0xf8, (address | l1 << 16 | 1 << 31));
+ pci_write_config_dword(iommu->dev, 0xfc, val);
+ pci_write_config_dword(iommu->dev, 0xf8, (address | l1 << 16));
+}
+
+static u32 iommu_read_l2(struct amd_iommu *iommu, u8 address)
+{
+ u32 val;
+
+ pci_write_config_dword(iommu->dev, 0xf0, address);
+ pci_read_config_dword(iommu->dev, 0xf4, &val);
+ return val;
+}
+
+static void iommu_write_l2(struct amd_iommu *iommu, u8 address, u32 val)
+{
+ pci_write_config_dword(iommu->dev, 0xf0, (address | 1 << 8));
+ pci_write_config_dword(iommu->dev, 0xf4, val);
+}
+
/****************************************************************************
*
* AMD IOMMU MMIO register space handling functions
@@ -619,6 +652,7 @@ static void __init init_iommu_from_pci(struct amd_iommu *iommu)
{
int cap_ptr = iommu->cap_ptr;
u32 range, misc;
+ int i, j;
pci_read_config_dword(iommu->dev, cap_ptr + MMIO_CAP_HDR_OFFSET,
&iommu->cap);
@@ -633,12 +667,29 @@ static void __init init_iommu_from_pci(struct amd_iommu *iommu)
MMIO_GET_LD(range));
iommu->evt_msi_num = MMIO_MSI_NUM(misc);
- if (is_rd890_iommu(iommu->dev)) {
- pci_read_config_dword(iommu->dev, 0xf0, &iommu->cache_cfg[0]);
- pci_read_config_dword(iommu->dev, 0xf4, &iommu->cache_cfg[1]);
- pci_read_config_dword(iommu->dev, 0xf8, &iommu->cache_cfg[2]);
- pci_read_config_dword(iommu->dev, 0xfc, &iommu->cache_cfg[3]);
- }
+ if (!is_rd890_iommu(iommu->dev))
+ return;
+
+ /*
+ * Some rd890 systems may not be fully reconfigured by the BIOS, so
+ * it's necessary for us to store this information so it can be
+ * reprogrammed on resume
+ */
+
+ pci_read_config_dword(iommu->dev, iommu->cap_ptr + 4,
+ &iommu->stored_addr_lo);
+ pci_read_config_dword(iommu->dev, iommu->cap_ptr + 8,
+ &iommu->stored_addr_hi);
+
+ /* Low bit locks writes to configuration space */
+ iommu->stored_addr_lo &= ~1;
+
+ for (i = 0; i < 6; i++)
+ for (j = 0; j < 0x12; j++)
+ iommu->stored_l1[i][j] = iommu_read_l1(iommu, i, j);
+
+ for (i = 0; i < 0x83; i++)
+ iommu->stored_l2[i] = iommu_read_l2(iommu, i);
}
/*
@@ -1127,14 +1178,53 @@ static void iommu_init_flags(struct amd_iommu *iommu)
iommu_feature_enable(iommu, CONTROL_COHERENT_EN);
}
-static void iommu_apply_quirks(struct amd_iommu *iommu)
+static void iommu_apply_resume_quirks(struct amd_iommu *iommu)
{
- if (is_rd890_iommu(iommu->dev)) {
- pci_write_config_dword(iommu->dev, 0xf0, iommu->cache_cfg[0]);
- pci_write_config_dword(iommu->dev, 0xf4, iommu->cache_cfg[1]);
- pci_write_config_dword(iommu->dev, 0xf8, iommu->cache_cfg[2]);
- pci_write_config_dword(iommu->dev, 0xfc, iommu->cache_cfg[3]);
- }
+ int i, j;
+ u32 ioc_feature_control;
+ struct pci_dev *pdev = NULL;
+
+ /* RD890 BIOSes may not have completely reconfigured the iommu */
+ if (!is_rd890_iommu(iommu->dev))
+ return;
+
+ /*
+ * First, we need to ensure that the iommu is enabled. This is
+ * controlled by a register in the northbridge
+ */
+ pdev = pci_get_bus_and_slot(iommu->dev->bus->number, PCI_DEVFN(0, 0));
+
+ if (!pdev)
+ return;
+
+ /* Select Northbridge indirect register 0x75 and enable writing */
+ pci_write_config_dword(pdev, 0x60, 0x75 | (1 << 7));
+ pci_read_config_dword(pdev, 0x64, &ioc_feature_control);
+
+ /* Enable the iommu */
+ if (!(ioc_feature_control & 0x1))
+ pci_write_config_dword(pdev, 0x64, ioc_feature_control | 1);
+
+ pci_dev_put(pdev);
+
+ /* Restore the iommu BAR */
+ pci_write_config_dword(iommu->dev, iommu->cap_ptr + 4,
+ iommu->stored_addr_lo);
+ pci_write_config_dword(iommu->dev, iommu->cap_ptr + 8,
+ iommu->stored_addr_hi);
+
+ /* Restore the l1 indirect regs for each of the 6 l1s */
+ for (i = 0; i < 6; i++)
+ for (j = 0; j < 0x12; j++)
+ iommu_write_l1(iommu, i, j, iommu->stored_l1[i][j]);
+
+ /* Restore the l2 indirect regs */
+ for (i = 0; i < 0x83; i++)
+ iommu_write_l2(iommu, i, iommu->stored_l2[i]);
+
+ /* Lock PCI setup registers */
+ pci_write_config_dword(iommu->dev, iommu->cap_ptr + 4,
+ iommu->stored_addr_lo | 1);
}
/*
@@ -1147,7 +1237,6 @@ static void enable_iommus(void)
for_each_iommu(iommu) {
iommu_disable(iommu);
- iommu_apply_quirks(iommu);
iommu_init_flags(iommu);
iommu_set_device_table(iommu);
iommu_enable_command_buffer(iommu);
@@ -1173,6 +1262,11 @@ static void disable_iommus(void)
static int amd_iommu_resume(struct sys_device *dev)
{
+ struct amd_iommu *iommu;
+
+ for_each_iommu(iommu)
+ iommu_apply_resume_quirks(iommu);
+
/* re-load the hardware */
enable_iommus();