From 80f0251231131d164eddab78d2b6c1b8e37d0093 Mon Sep 17 00:00:00 2001 From: Leonardo Bras Date: Wed, 5 Aug 2020 00:04:53 -0300 Subject: [PATCH] powerpc/pseries/iommu: Update call to ibm, query-pe-dma-windows >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 Tested-by: David Dai Reviewed-by: Alexey Kardashevskiy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200805030455.123024-3-leobras.c@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; -- 2.11.0