summaryrefslogtreecommitdiff
path: root/arch/powerpc/sysdev/dart_iommu.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/powerpc/sysdev/dart_iommu.c')
-rw-r--r--arch/powerpc/sysdev/dart_iommu.c184
1 files changed, 88 insertions, 96 deletions
diff --git a/arch/powerpc/sysdev/dart_iommu.c b/arch/powerpc/sysdev/dart_iommu.c
index b7348637eae0..26904f4879ec 100644
--- a/arch/powerpc/sysdev/dart_iommu.c
+++ b/arch/powerpc/sysdev/dart_iommu.c
@@ -48,16 +48,10 @@
#include "dart.h"
-/* Physical base address and size of the DART table */
-unsigned long dart_tablebase; /* exported to htab_initialize */
+/* DART table address and size */
+static u32 *dart_tablebase;
static unsigned long dart_tablesize;
-/* Virtual base address of the DART table */
-static u32 *dart_vbase;
-#ifdef CONFIG_PM
-static u32 *dart_copy;
-#endif
-
/* Mapped base address for the dart */
static unsigned int __iomem *dart;
@@ -151,6 +145,34 @@ wait_more:
spin_unlock_irqrestore(&invalidate_lock, flags);
}
+static void dart_cache_sync(unsigned int *base, unsigned int count)
+{
+ /*
+ * We add 1 to the number of entries to flush, following a
+ * comment in Darwin indicating that the memory controller
+ * can prefetch unmapped memory under some circumstances.
+ */
+ unsigned long start = (unsigned long)base;
+ unsigned long end = start + (count + 1) * sizeof(unsigned int);
+ unsigned int tmp;
+
+ /* Perform a standard cache flush */
+ flush_inval_dcache_range(start, end);
+
+ /*
+ * Perform the sequence described in the CPC925 manual to
+ * ensure all the data gets to a point the cache incoherent
+ * DART hardware will see.
+ */
+ asm volatile(" sync;"
+ " isync;"
+ " dcbf 0,%1;"
+ " sync;"
+ " isync;"
+ " lwz %0,0(%1);"
+ " isync" : "=r" (tmp) : "r" (end) : "memory");
+}
+
static void dart_flush(struct iommu_table *tbl)
{
mb();
@@ -165,13 +187,13 @@ static int dart_build(struct iommu_table *tbl, long index,
enum dma_data_direction direction,
struct dma_attrs *attrs)
{
- unsigned int *dp;
+ unsigned int *dp, *orig_dp;
unsigned int rpn;
long l;
DBG("dart: build at: %lx, %lx, addr: %x\n", index, npages, uaddr);
- dp = ((unsigned int*)tbl->it_base) + index;
+ orig_dp = dp = ((unsigned int*)tbl->it_base) + index;
/* On U3, all memory is contiguous, so we can move this
* out of the loop.
@@ -184,11 +206,7 @@ static int dart_build(struct iommu_table *tbl, long index,
uaddr += DART_PAGE_SIZE;
}
-
- /* make sure all updates have reached memory */
- mb();
- in_be32((unsigned __iomem *)dp);
- mb();
+ dart_cache_sync(orig_dp, npages);
if (dart_is_u4) {
rpn = index;
@@ -203,7 +221,8 @@ static int dart_build(struct iommu_table *tbl, long index,
static void dart_free(struct iommu_table *tbl, long index, long npages)
{
- unsigned int *dp;
+ unsigned int *dp, *orig_dp;
+ long orig_npages = npages;
/* We don't worry about flushing the TLB cache. The only drawback of
* not doing it is that we won't catch buggy device drivers doing
@@ -212,34 +231,30 @@ static void dart_free(struct iommu_table *tbl, long index, long npages)
DBG("dart: free at: %lx, %lx\n", index, npages);
- dp = ((unsigned int *)tbl->it_base) + index;
+ orig_dp = dp = ((unsigned int *)tbl->it_base) + index;
while (npages--)
*(dp++) = dart_emptyval;
-}
+ dart_cache_sync(orig_dp, orig_npages);
+}
-static int __init dart_init(struct device_node *dart_node)
+static void allocate_dart(void)
{
- unsigned int i;
- unsigned long tmp, base, size;
- struct resource r;
-
- if (dart_tablebase == 0 || dart_tablesize == 0) {
- printk(KERN_INFO "DART: table not allocated, using "
- "direct DMA\n");
- return -ENODEV;
- }
+ unsigned long tmp;
- if (of_address_to_resource(dart_node, 0, &r))
- panic("DART: can't get register base ! ");
+ /* 512 pages (2MB) is max DART tablesize. */
+ dart_tablesize = 1UL << 21;
- /* Make sure nothing from the DART range remains in the CPU cache
- * from a previous mapping that existed before the kernel took
- * over
+ /*
+ * 16MB (1 << 24) alignment. We allocate a full 16Mb chuck since we
+ * will blow up an entire large page anyway in the kernel mapping.
*/
- flush_dcache_phys_range(dart_tablebase,
- dart_tablebase + dart_tablesize);
+ dart_tablebase = __va(memblock_alloc_base(1UL<<24,
+ 1UL<<24, 0x80000000L));
+
+ /* There is no point scanning the DART space for leaks*/
+ kmemleak_no_scan((void *)dart_tablebase);
/* Allocate a spare page to map all invalid DART pages. We need to do
* that to work around what looks like a problem with the HT bridge
@@ -249,20 +264,51 @@ static int __init dart_init(struct device_node *dart_node)
dart_emptyval = DARTMAP_VALID | ((tmp >> DART_PAGE_SHIFT) &
DARTMAP_RPNMASK);
+ printk(KERN_INFO "DART table allocated at: %p\n", dart_tablebase);
+}
+
+static int __init dart_init(struct device_node *dart_node)
+{
+ unsigned int i;
+ unsigned long base, size;
+ struct resource r;
+
+ /* IOMMU disabled by the user ? bail out */
+ if (iommu_is_off)
+ return -ENODEV;
+
+ /*
+ * Only use the DART if the machine has more than 1GB of RAM
+ * or if requested with iommu=on on cmdline.
+ *
+ * 1GB of RAM is picked as limit because some default devices
+ * (i.e. Airport Extreme) have 30 bit address range limits.
+ */
+
+ if (!iommu_force_on && memblock_end_of_DRAM() <= 0x40000000ull)
+ return -ENODEV;
+
+ /* Get DART registers */
+ if (of_address_to_resource(dart_node, 0, &r))
+ panic("DART: can't get register base ! ");
+
/* Map in DART registers */
dart = ioremap(r.start, resource_size(&r));
if (dart == NULL)
panic("DART: Cannot map registers!");
- /* Map in DART table */
- dart_vbase = ioremap(__pa(dart_tablebase), dart_tablesize);
+ /* Allocate the DART and dummy page */
+ allocate_dart();
/* Fill initial table */
for (i = 0; i < dart_tablesize/4; i++)
- dart_vbase[i] = dart_emptyval;
+ dart_tablebase[i] = dart_emptyval;
+
+ /* Push to memory */
+ dart_cache_sync(dart_tablebase, dart_tablesize / sizeof(u32));
/* Initialize DART with table base and enable it. */
- base = dart_tablebase >> DART_PAGE_SHIFT;
+ base = ((unsigned long)dart_tablebase) >> DART_PAGE_SHIFT;
size = dart_tablesize >> DART_PAGE_SHIFT;
if (dart_is_u4) {
size &= DART_SIZE_U4_SIZE_MASK;
@@ -301,7 +347,7 @@ static void iommu_table_dart_setup(void)
iommu_table_dart.it_page_shift = IOMMU_PAGE_SHIFT_4K;
/* Initialize the common IOMMU code */
- iommu_table_dart.it_base = (unsigned long)dart_vbase;
+ iommu_table_dart.it_base = (unsigned long)dart_tablebase;
iommu_table_dart.it_index = 0;
iommu_table_dart.it_blocksize = 1;
iommu_table_dart.it_ops = &iommu_dart_ops;
@@ -404,75 +450,21 @@ void __init iommu_init_early_dart(struct pci_controller_ops *controller_ops)
}
#ifdef CONFIG_PM
-static void iommu_dart_save(void)
-{
- memcpy(dart_copy, dart_vbase, 2*1024*1024);
-}
-
static void iommu_dart_restore(void)
{
- memcpy(dart_vbase, dart_copy, 2*1024*1024);
+ dart_cache_sync(dart_tablebase, dart_tablesize / sizeof(u32));
dart_tlb_invalidate_all();
}
static int __init iommu_init_late_dart(void)
{
- unsigned long tbasepfn;
- struct page *p;
-
- /* if no dart table exists then we won't need to save it
- * and the area has also not been reserved */
if (!dart_tablebase)
return 0;
- tbasepfn = __pa(dart_tablebase) >> PAGE_SHIFT;
- register_nosave_region_late(tbasepfn,
- tbasepfn + ((1<<24) >> PAGE_SHIFT));
-
- /* For suspend we need to copy the dart contents because
- * it is not part of the regular mapping (see above) and
- * thus not saved automatically. The memory for this copy
- * must be allocated early because we need 2 MB. */
- p = alloc_pages(GFP_KERNEL, 21 - PAGE_SHIFT);
- BUG_ON(!p);
- dart_copy = page_address(p);
-
- ppc_md.iommu_save = iommu_dart_save;
ppc_md.iommu_restore = iommu_dart_restore;
return 0;
}
late_initcall(iommu_init_late_dart);
-#endif
-
-void __init alloc_dart_table(void)
-{
- /* Only reserve DART space if machine has more than 1GB of RAM
- * or if requested with iommu=on on cmdline.
- *
- * 1GB of RAM is picked as limit because some default devices
- * (i.e. Airport Extreme) have 30 bit address range limits.
- */
-
- if (iommu_is_off)
- return;
-
- if (!iommu_force_on && memblock_end_of_DRAM() <= 0x40000000ull)
- return;
-
- /* 512 pages (2MB) is max DART tablesize. */
- dart_tablesize = 1UL << 21;
- /* 16MB (1 << 24) alignment. We allocate a full 16Mb chuck since we
- * will blow up an entire large page anyway in the kernel mapping
- */
- dart_tablebase = (unsigned long)
- __va(memblock_alloc_base(1UL<<24, 1UL<<24, 0x80000000L));
- /*
- * The DART space is later unmapped from the kernel linear mapping and
- * accessing dart_tablebase during kmemleak scanning will fault.
- */
- kmemleak_no_scan((void *)dart_tablebase);
-
- printk(KERN_INFO "DART table allocated at: %lx\n", dart_tablebase);
-}
+#endif /* CONFIG_PM */