>From LoPAR level 2.8, "ibm,ddw-extensions" index 3 can make the number of
outputs from "ibm,query-pe-dma-windows" go from 5 to 6.
This change of output size is meant to expand the address size of
largest_available_block PE TCE from 32-bit to 64-bit, which ends up
shifting page_size and migration_capable.
This ends up requiring the update of
ddw_query_response->largest_available_block from u32 to u64, and manually
assigning the values from the buffer into this struct, according to
output size.
Also, a routine was created for helping reading the ddw extensions as
suggested by LoPAR: First reading the size of the extension array from
index 0, checking if the property exists, and then returning it's value.
Signed-off-by: Leonardo Bras <leobra...@gmail.com>
---
arch/powerpc/platforms/pseries/iommu.c | 91 +++++++++++++++++++++++---
1 file changed, 81 insertions(+), 10 deletions(-)
diff --git a/arch/powerpc/platforms/pseries/iommu.c
b/arch/powerpc/platforms/pseries/iommu.c
index ac0d6376bdad..1a933c4e8bba 100644
--- a/arch/powerpc/platforms/pseries/iommu.c
+++ b/arch/powerpc/platforms/pseries/iommu.c
@@ -47,6 +47,12 @@ enum {
DDW_APPLICABLE_SIZE
};
+enum {
+ DDW_EXT_SIZE = 0,
+ DDW_EXT_RESET_DMA_WIN = 1,
+ DDW_EXT_QUERY_OUT_SIZE = 2
+};
+
static struct iommu_table_group *iommu_pseries_alloc_group(int node)
{
struct iommu_table_group *table_group;
@@ -342,7 +348,7 @@ struct direct_window {
/* Dynamic DMA Window support */
struct ddw_query_response {
u32 windows_available;
- u32 largest_available_block;
+ u64 largest_available_block;
u32 page_size;
u32 migration_capable;
};
@@ -877,14 +883,62 @@ static int find_existing_ddw_windows(void)
}
machine_arch_initcall(pseries, find_existing_ddw_windows);
+/**
+ * ddw_read_ext - Get the value of an DDW extension
+ * @np: device node from which the extension value is to be
read.
+ * @extnum: index number of the extension.
+ * @value: pointer to return value, modified when extension is available.
+ *
+ * Checks if "ibm,ddw-extensions" exists for this node, and get the value
+ * on index 'extnum'.
+ * It can be used only to check if a property exists, passing value == NULL.
+ *
+ * Returns:
+ * 0 if extension successfully read
+ * -EINVAL if the "ibm,ddw-extensions" does not exist,
+ * -ENODATA if "ibm,ddw-extensions" does not have a value, and
+ * -EOVERFLOW if "ibm,ddw-extensions" does not contain this extension.
+ */
+static inline int ddw_read_ext(const struct device_node *np, int extnum,
+ u32 *value)
+{
+ static const char propname[] = "ibm,ddw-extensions";
+ u32 count;
+ int ret;
+
+ ret = of_property_read_u32_index(np, propname, DDW_EXT_SIZE, &count);
+ if (ret)
+ return ret;
+
+ if (count < extnum)
+ return -EOVERFLOW;
+
+ if (!value)
+ value = &count;
+
+ return of_property_read_u32_index(np, propname, extnum, value);
+}
+
static int query_ddw(struct pci_dev *dev, const u32 *ddw_avail,
- struct ddw_query_response *query)
+ struct ddw_query_response *query,
+ struct device_node *parent)
{
struct device_node *dn;
struct pci_dn *pdn;
- u32 cfg_addr;
+ u32 cfg_addr, ext_query, query_out[5];
u64 buid;
- int ret;
+ int ret, out_sz;
+
+ /*
+ * From LoPAR level 2.8, "ibm,ddw-extensions" index 3 can rule how many
+ * output parameters ibm,query-pe-dma-windows will have, ranging from
+ * 5 to 6.
+ */
+ ret = ddw_read_ext(parent, DDW_EXT_QUERY_OUT_SIZE, &ext_query);
+ if (!ret && ext_query == 1)
+ out_sz = 6;
+ else
+ out_sz = 5;
/*
* Get the config address and phb buid of the PE window.
@@ -897,11 +951,28 @@ static int query_ddw(struct pci_dev *dev, const u32
*ddw_avail,
buid = pdn->phb->buid;
cfg_addr = ((pdn->busno << 16) | (pdn->devfn << 8));
- ret = rtas_call(ddw_avail[DDW_QUERY_PE_DMA_WIN], 3, 5, (u32 *)query,
+ ret = rtas_call(ddw_avail[DDW_QUERY_PE_DMA_WIN], 3, out_sz, query_out,
cfg_addr, BUID_HI(buid), BUID_LO(buid));
- dev_info(&dev->dev, "ibm,query-pe-dma-windows(%x) %x %x %x"
- " returned %d\n", ddw_avail[DDW_QUERY_PE_DMA_WIN], cfg_addr,
- BUID_HI(buid), BUID_LO(buid), ret);
+ dev_info(&dev->dev, "ibm,query-pe-dma-windows(%x) %x %x %x returned
%d\n",
+ ddw_avail[DDW_QUERY_PE_DMA_WIN], cfg_addr, BUID_HI(buid),
+ BUID_LO(buid), ret);
+
+ switch (out_sz) {
+ case 5:
+ query->windows_available = query_out[0];
+ query->largest_available_block = query_out[1];
+ query->page_size = query_out[2];
+ query->migration_capable = query_out[3];
+ break;
+ case 6:
+ query->windows_available = query_out[0];
+ query->largest_available_block = ((u64)query_out[1] << 32) |
+ query_out[2];
+ query->page_size = query_out[3];
+ query->migration_capable = query_out[4];
+ break;
+ }
+
return ret;
}
@@ -1049,7 +1120,7 @@ static u64 enable_ddw(struct pci_dev *dev, struct
device_node *pdn)
* of page sizes: supported and supported for migrate-dma.
*/
dn = pci_device_to_OF_node(dev);
- ret = query_ddw(dev, ddw_avail, &query);
+ ret = query_ddw(dev, ddw_avail, &query, pdn);
if (ret != 0)
goto out_failed;
@@ -1077,7 +1148,7 @@ static u64 enable_ddw(struct pci_dev *dev, struct
device_node *pdn)
/* check largest block * page size > max memory hotplug addr */
max_addr = ddw_memory_hotplug_max();
if (query.largest_available_block < (max_addr >> page_shift)) {
- dev_dbg(&dev->dev, "can't map partition max 0x%llx with %u "
+ dev_dbg(&dev->dev, "can't map partition max 0x%llx with %llu "
"%llu-sized pages\n", max_addr,
query.largest_available_block,
1ULL << page_shift);
goto out_failed;
--
2.25.4
