[PATCH] powerpc: dart iommu suspend

Johannes Berg
2007-05-03T12:27:34Z

This implements save and restore hooks for IOMMUs and implements
it the dart iommu.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: Paul Mackeras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Olof Johansson <olof@lixom.net>

---
arch/powerpc/sysdev/dart_iommu.c | 46 +++++++++++++++++++++++++++++++++++++++
include/asm-powerpc/iommu.h | 14 +++++++++++
include/asm-powerpc/machdep.h | 5 ++++
3 files changed, 65 insertions(+)

--- wireless-dev.orig/arch/powerpc/sysdev/dart_iommu.c 2007-05-03 14:20:26.089165535 +0200
+++ wireless-dev/arch/powerpc/sysdev/dart_iommu.c 2007-05-03 14:21:08.889165535 +0200
@@ -36,6 +36,7 @@
#include <linux/pci.h>
#include <linux/dma-mapping.h>
#include <linux/vmalloc.h>
+#include <linux/suspend.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/iommu.h>
@@ -54,6 +55,9 @@ 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;
@@ -346,6 +350,48 @@ void iommu_init_early_dart(void)
set_pci_dma_ops(&dma_direct_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_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)
{
--- wireless-dev.orig/include/asm-powerpc/iommu.h 2007-05-03 14:20:26.109165535 +0200
+++ wireless-dev/include/asm-powerpc/iommu.h 2007-05-03 14:21:08.889165535 +0200
@@ -26,6 +26,7 @@
#include <linux/spinlock.h>
#include <linux/device.h>
#include <linux/dma-mapping.h>
+#include <asm/machdep.h>
#include <asm/types.h>
#include <asm/bitops.h>

@@ -109,6 +110,19 @@ static inline void pci_iommu_init(void)
#endif

extern void alloc_dart_table(void);
+#if defined(CONFIG_PPC64) && defined(CONFIG_PM)
+static inline void iommu_save(void)
+{
+ if (ppc_md.iommu_save)
+ ppc_md.iommu_save();
+}
+
+static inline void iommu_restore(void)
+{
+ if (ppc_md.iommu_restore)
+ ppc_md.iommu_restore();
+}
+#endif

#endif /* __KERNEL__ */
#endif /* _ASM_IOMMU_H */
--- wireless-dev.orig/include/asm-powerpc/machdep.h 2007-05-03 14:21:07.569165535 +0200
+++ wireless-dev/include/asm-powerpc/machdep.h 2007-05-03 14:21:08.899165535 +0200
@@ -91,6 +91,11 @@ struct machdep_calls {
void __iomem * (*ioremap)(phys_addr_t addr, unsigned long size,
unsigned long flags);
void (*iounmap)(volatile void __iomem *token);
+
+#ifdef CONFIG_PM
+ void (*iommu_save)(void);
+ void (*iommu_restore)(void);
+#endif
#endif /* CONFIG_PPC64 */

int (*probe)(void);