Merge tag 'dt-for-3.6' of git://sources.calxeda.com/kernel/linux
[linux-3.10.git] / arch / powerpc / platforms / pseries / iommu.c
index 6b58a39..bca220f 100644 (file)
@@ -192,12 +192,15 @@ static int tce_buildmulti_pSeriesLP(struct iommu_table *tbl, long tcenum,
        long l, limit;
        long tcenum_start = tcenum, npages_start = npages;
        int ret = 0;
+       unsigned long flags;
 
        if (npages == 1) {
                return tce_build_pSeriesLP(tbl, tcenum, npages, uaddr,
                                           direction, attrs);
        }
 
+       local_irq_save(flags);  /* to protect tcep and the page behind it */
+
        tcep = __get_cpu_var(tce_page);
 
        /* This is safe to do since interrupts are off when we're called
@@ -207,6 +210,7 @@ static int tce_buildmulti_pSeriesLP(struct iommu_table *tbl, long tcenum,
                tcep = (u64 *)__get_free_page(GFP_ATOMIC);
                /* If allocation fails, fall back to the loop implementation */
                if (!tcep) {
+                       local_irq_restore(flags);
                        return tce_build_pSeriesLP(tbl, tcenum, npages, uaddr,
                                            direction, attrs);
                }
@@ -240,6 +244,8 @@ static int tce_buildmulti_pSeriesLP(struct iommu_table *tbl, long tcenum,
                tcenum += limit;
        } while (npages > 0 && !rc);
 
+       local_irq_restore(flags);
+
        if (unlikely(rc == H_NOT_ENOUGH_RESOURCES)) {
                ret = (int)rc;
                tce_freemulti_pSeriesLP(tbl, tcenum_start,
@@ -707,6 +713,21 @@ 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 +757,7 @@ 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 +882,35 @@ 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 +931,13 @@ 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 +957,40 @@ 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 +999,7 @@ 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 +1008,7 @@ 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 +1019,7 @@ 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 +1028,14 @@ 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 +1097,10 @@ out_free_prop:
        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;