ACPI: scan: Support multiple DMA windows with different offsets

In DT systems configurations, of_dma_get_range() returns struct
bus_dma_region DMA regions; they are used to set-up devices
DMA windows with different offset available for translation between DMA
address and CPU address.

In ACPI systems configuration, acpi_dma_get_range() does not return
DMA regions yet and that precludes setting up the dev->dma_range_map
pointer and therefore DMA regions with multiple offsets.

Update acpi_dma_get_range() to return struct bus_dma_region
DMA regions like of_dma_get_range() does.

After updating acpi_dma_get_range(), acpi_arch_dma_setup() is changed for
ARM64, where the original dma_addr and size are removed as these
arguments are now redundant, and pass 0 and U64_MAX for dma_base
and size of arch_setup_dma_ops; this is a simplification consistent
with what other ACPI architectures also pass to iommu_setup_dma_ops().

Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Jianmin Lv <lvjianmin@loongson.cn>
Reviewed-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/arm64/dma.c b/drivers/acpi/arm64/dma.c
index f16739a..93d7965 100644 (file)
--- a/drivers/acpi/arm64/dma.c
+++ b/drivers/acpi/arm64/dma.c
@@ -4,11 +4,12 @@
 #include <linux/device.h>
 #include <linux/dma-direct.h>
 
-void acpi_arch_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size)
+void acpi_arch_dma_setup(struct device *dev)
 {
        int ret;
        u64 end, mask;
-       u64 dmaaddr = 0, size = 0, offset = 0;
+       u64 size = 0;
+       const struct bus_dma_region *map = NULL;
 
        /*
         * If @dev is expected to be DMA-capable then the bus code that created
@@ -26,7 +27,19 @@ void acpi_arch_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size)
        else
                size = 1ULL << 32;
 
-       ret = acpi_dma_get_range(dev, &dmaaddr, &offset, &size);
+       ret = acpi_dma_get_range(dev, &map);
+       if (!ret && map) {
+               const struct bus_dma_region *r = map;
+
+               for (end = 0; r->size; r++) {
+                       if (r->dma_start + r->size - 1 > end)
+                               end = r->dma_start + r->size - 1;
+               }
+
+               size = end + 1;
+               dev->dma_range_map = map;
+       }
+
        if (ret == -ENODEV)
                ret = iort_dma_get_ranges(dev, &size);
        if (!ret) {
@@ -34,17 +47,10 @@ void acpi_arch_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size)
                 * Limit coherent and dma mask based on size retrieved from
                 * firmware.
                 */
-               end = dmaaddr + size - 1;
+               end = size - 1;
                mask = DMA_BIT_MASK(ilog2(end) + 1);
                dev->bus_dma_limit = end;
                dev->coherent_dma_mask = min(dev->coherent_dma_mask, mask);
                *dev->dma_mask = min(*dev->dma_mask, mask);
        }
-
-       *dma_addr = dmaaddr;
-       *dma_size = size;
-
-       ret = dma_direct_set_offset(dev, dmaaddr + offset, dmaaddr, size);
-
-       dev_dbg(dev, "dma_offset(%#08llx)%s\n", offset, ret ? " failed!" : "");
 }

diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 42cec81..f96ef85 100644 (file)
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -20,6 +20,7 @@
 #include <linux/platform_data/x86/apple.h>
 #include <linux/pgtable.h>
 #include <linux/crc32.h>
+#include <linux/dma-direct.h>
 
 #include "internal.h"
 
@@ -1467,25 +1468,21 @@ enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
  * acpi_dma_get_range() - Get device DMA parameters.
  *
  * @dev: device to configure
- * @dma_addr: pointer device DMA address result
- * @offset: pointer to the DMA offset result
- * @size: pointer to DMA range size result
+ * @map: pointer to DMA ranges result
  *
- * Evaluate DMA regions and return respectively DMA region start, offset
- * and size in dma_addr, offset and size on parsing success; it does not
- * update the passed in values on failure.
+ * Evaluate DMA regions and return pointer to DMA regions on
+ * parsing success; it does not update the passed in values on failure.
  *
  * Return 0 on success, < 0 on failure.
  */
-int acpi_dma_get_range(struct device *dev, u64 *dma_addr, u64 *offset,
-                      u64 *size)
+int acpi_dma_get_range(struct device *dev, const struct bus_dma_region **map)
 {
        struct acpi_device *adev;
        LIST_HEAD(list);
        struct resource_entry *rentry;
        int ret;
        struct device *dma_dev = dev;
-       u64 len, dma_start = U64_MAX, dma_end = 0, dma_offset = 0;
+       struct bus_dma_region *r;
 
        /*
         * Walk the device tree chasing an ACPI companion with a _DMA
@@ -1510,31 +1507,28 @@ int acpi_dma_get_range(struct device *dev, u64 *dma_addr, u64 *offset,
 
        ret = acpi_dev_get_dma_resources(adev, &list);
        if (ret > 0) {
+               r = kcalloc(ret + 1, sizeof(*r), GFP_KERNEL);
+               if (!r) {
+                       ret = -ENOMEM;
+                       goto out;
+               }
+
                list_for_each_entry(rentry, &list, node) {
-                       if (dma_offset && rentry->offset != dma_offset) {
+                       if (rentry->res->start >= rentry->res->end) {
+                               kfree(r);
                                ret = -EINVAL;
-                               dev_warn(dma_dev, "Can't handle multiple windows with different offsets\n");
+                               dev_dbg(dma_dev, "Invalid DMA regions configuration\n");
                                goto out;
                        }
-                       dma_offset = rentry->offset;
 
-                       /* Take lower and upper limits */
-                       if (rentry->res->start < dma_start)
-                               dma_start = rentry->res->start;
-                       if (rentry->res->end > dma_end)
-                               dma_end = rentry->res->end;
-               }
-
-               if (dma_start >= dma_end) {
-                       ret = -EINVAL;
-                       dev_dbg(dma_dev, "Invalid DMA regions configuration\n");
-                       goto out;
+                       r->cpu_start = rentry->res->start;
+                       r->dma_start = rentry->res->start - rentry->offset;
+                       r->size = resource_size(rentry->res);
+                       r->offset = rentry->offset;
+                       r++;
                }
 
-               *dma_addr = dma_start - dma_offset;
-               len = dma_end - dma_start;
-               *size = max(len, len + 1);
-               *offset = dma_offset;
+               *map = r;
        }
  out:
        acpi_dev_free_resource_list(&list);
@@ -1624,20 +1618,19 @@ int acpi_dma_configure_id(struct device *dev, enum dev_dma_attr attr,
                          const u32 *input_id)
 {
        const struct iommu_ops *iommu;
-       u64 dma_addr = 0, size = 0;
 
        if (attr == DEV_DMA_NOT_SUPPORTED) {
                set_dma_ops(dev, &dma_dummy_ops);
                return 0;
        }
 
-       acpi_arch_dma_setup(dev, &dma_addr, &size);
+       acpi_arch_dma_setup(dev);
 
        iommu = acpi_iommu_configure_id(dev, input_id);
        if (PTR_ERR(iommu) == -EPROBE_DEFER)
                return -EPROBE_DEFER;
 
-       arch_setup_dma_ops(dev, dma_addr, size,
+       arch_setup_dma_ops(dev, 0, U64_MAX,
                                iommu, attr == DEV_DMA_COHERENT);
 
        return 0;

diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index e7d2737..73ac4a1 100644 (file)
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -613,8 +613,7 @@ enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev);
 int acpi_iommu_fwspec_init(struct device *dev, u32 id,
                           struct fwnode_handle *fwnode,
                           const struct iommu_ops *ops);
-int acpi_dma_get_range(struct device *dev, u64 *dma_addr, u64 *offset,
-                      u64 *size);
+int acpi_dma_get_range(struct device *dev, const struct bus_dma_region **map);
 int acpi_dma_configure_id(struct device *dev, enum dev_dma_attr attr,
                           const u32 *input_id);
 static inline int acpi_dma_configure(struct device *dev,

diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 6f64b2f..bb41623 100644 (file)
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -281,12 +281,12 @@ void acpi_numa_x2apic_affinity_init(struct acpi_srat_x2apic_cpu_affinity *pa);
 
 #ifdef CONFIG_ARM64
 void acpi_numa_gicc_affinity_init(struct acpi_srat_gicc_affinity *pa);
-void acpi_arch_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size);
+void acpi_arch_dma_setup(struct device *dev);
 #else
 static inline void
 acpi_numa_gicc_affinity_init(struct acpi_srat_gicc_affinity *pa) { }
 static inline void
-acpi_arch_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size) { }
+acpi_arch_dma_setup(struct device *dev) { }
 #endif
 
 int acpi_numa_memory_affinity_init (struct acpi_srat_mem_affinity *ma);
@@ -977,8 +977,7 @@ static inline enum dev_dma_attr acpi_get_dma_attr(struct acpi_device *adev)
        return DEV_DMA_NOT_SUPPORTED;
 }
 
-static inline int acpi_dma_get_range(struct device *dev, u64 *dma_addr,
-                                    u64 *offset, u64 *size)
+static inline int acpi_dma_get_range(struct device *dev, const struct bus_dma_region **map)
 {
        return -ENODEV;
 }