diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c index 2d311c0caf8e..d5d1dd58ca74 100644 --- a/arch/powerpc/platforms/pseries/iommu.c +++ b/arch/powerpc/platforms/pseries/iommu.c @@ -707,6 +707,21 @@ static int __init disable_ddw_setup(char *str) early_param("disable_ddw", disable_ddw_setup); +static inline void __remove_ddw(struct device_node *np, const u32 *ddw_avail, u64 liobn) +{ + int ret; + + ret = rtas_call(ddw_avail[2], 1, 1, NULL, liobn); + if (ret) + pr_warning("%s: failed to remove DMA window: rtas returned " + "%d to ibm,remove-pe-dma-window(%x) %llx\n", + np->full_name, ret, ddw_avail[2], liobn); + else + pr_debug("%s: successfully removed DMA window: rtas returned " + "%d to ibm,remove-pe-dma-window(%x) %llx\n", + np->full_name, ret, ddw_avail[2], liobn); +} + static void remove_ddw(struct device_node *np) { struct dynamic_dma_window_prop *dwp; @@ -736,15 +751,7 @@ static void remove_ddw(struct device_node *np) pr_debug("%s successfully cleared tces in window.\n", np->full_name); - ret = rtas_call(ddw_avail[2], 1, 1, NULL, liobn); - if (ret) - pr_warning("%s: failed to remove direct window: rtas returned " - "%d to ibm,remove-pe-dma-window(%x) %llx\n", - np->full_name, ret, ddw_avail[2], liobn); - else - pr_debug("%s: successfully removed direct window: rtas returned " - "%d to ibm,remove-pe-dma-window(%x) %llx\n", - np->full_name, ret, ddw_avail[2], liobn); + __remove_ddw(np, ddw_avail, liobn); delprop: ret = prom_remove_property(np, win64); @@ -869,6 +876,35 @@ static int create_ddw(struct pci_dev *dev, const u32 *ddw_avail, return ret; } +static void restore_default_window(struct pci_dev *dev, + u32 ddw_restore_token, unsigned long liobn) +{ + struct eeh_dev *edev; + u32 cfg_addr; + u64 buid; + int ret; + + /* + * Get the config address and phb buid of the PE window. + * Rely on eeh to retrieve this for us. + * Retrieve them from the pci device, not the node with the + * dma-window property + */ + edev = pci_dev_to_eeh_dev(dev); + cfg_addr = edev->config_addr; + if (edev->pe_config_addr) + cfg_addr = edev->pe_config_addr; + buid = edev->phb->buid; + + do { + ret = rtas_call(ddw_restore_token, 3, 1, NULL, cfg_addr, + BUID_HI(buid), BUID_LO(buid)); + } while (rtas_busy_delay(ret)); + dev_info(&dev->dev, + "ibm,reset-pe-dma-windows(%x) %x %x %x returned %d\n", + ddw_restore_token, cfg_addr, BUID_HI(buid), BUID_LO(buid), ret); +} + /* * If the PE supports dynamic dma windows, and there is space for a table * that can map all pages in a linear offset, then setup such a table, @@ -889,9 +925,13 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) u64 dma_addr, max_addr; struct device_node *dn; const u32 *uninitialized_var(ddw_avail); + const u32 *uninitialized_var(ddw_extensions); + u32 ddw_restore_token = 0; struct direct_window *window; struct property *win64; struct dynamic_dma_window_prop *ddwprop; + const void *dma_window = NULL; + unsigned long liobn, offset, size; mutex_lock(&direct_window_init_mutex); @@ -911,7 +951,40 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) if (!ddw_avail || len < 3 * sizeof(u32)) goto out_unlock; - /* + /* + * the extensions property is only required to exist in certain + * levels of firmware and later + * the ibm,ddw-extensions property is a list with the first + * element containing the number of extensions and each + * subsequent entry is a value corresponding to that extension + */ + ddw_extensions = of_get_property(pdn, "ibm,ddw-extensions", &len); + if (ddw_extensions) { + /* + * each new defined extension length should be added to + * the top of the switch so the "earlier" entries also + * get picked up + */ + switch (ddw_extensions[0]) { + /* ibm,reset-pe-dma-windows */ + case 1: + ddw_restore_token = ddw_extensions[1]; + break; + } + } + + /* + * Only remove the existing DMA window if we can restore back to + * the default state. Removing the existing window maximizes the + * resources available to firmware for dynamic window creation. + */ + if (ddw_restore_token) { + dma_window = of_get_property(pdn, "ibm,dma-window", NULL); + of_parse_dma_window(pdn, dma_window, &liobn, &offset, &size); + __remove_ddw(pdn, ddw_avail, liobn); + } + + /* * Query if there is a second window of size to map the * whole partition. Query returns number of windows, largest * block assigned to PE (partition endpoint), and two bitmasks @@ -920,7 +993,7 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) dn = pci_device_to_OF_node(dev); ret = query_ddw(dev, ddw_avail, &query); if (ret != 0) - goto out_unlock; + goto out_restore_window; if (query.windows_available == 0) { /* @@ -929,7 +1002,7 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) * trading in for a larger page size. */ dev_dbg(&dev->dev, "no free dynamic windows"); - goto out_unlock; + goto out_restore_window; } if (query.page_size & 4) { page_shift = 24; /* 16MB */ @@ -940,7 +1013,7 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) } else { dev_dbg(&dev->dev, "no supported direct page size in mask %x", query.page_size); - goto out_unlock; + goto out_restore_window; } /* verify the window * number of ptes will map the partition */ /* check largest block * page size > max memory hotplug addr */ @@ -949,14 +1022,14 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) dev_dbg(&dev->dev, "can't map partiton max 0x%llx with %u " "%llu-sized pages\n", max_addr, query.largest_available_block, 1ULL << page_shift); - goto out_unlock; + goto out_restore_window; } len = order_base_2(max_addr); win64 = kzalloc(sizeof(struct property), GFP_KERNEL); if (!win64) { dev_info(&dev->dev, "couldn't allocate property for 64bit dma window\n"); - goto out_unlock; + goto out_restore_window; } win64->name = kstrdup(DIRECT64_PROPNAME, GFP_KERNEL); win64->value = ddwprop = kmalloc(sizeof(*ddwprop), GFP_KERNEL); @@ -1018,6 +1091,10 @@ static u64 enable_ddw(struct pci_dev *dev, struct device_node *pdn) kfree(win64->value); kfree(win64); +out_restore_window: + if (ddw_restore_token) + restore_default_window(dev, ddw_restore_token, liobn); + out_unlock: mutex_unlock(&direct_window_init_mutex); return dma_addr;