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-rw-r--r--arch/mips/cavium-octeon/dma-octeon.c311
1 files changed, 309 insertions, 2 deletions
diff --git a/arch/mips/cavium-octeon/dma-octeon.c b/arch/mips/cavium-octeon/dma-octeon.c
index 01b1ef94b36..627c162a615 100644
--- a/arch/mips/cavium-octeon/dma-octeon.c
+++ b/arch/mips/cavium-octeon/dma-octeon.c
@@ -13,20 +13,327 @@
*/
#include <linux/types.h>
#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/dma-mapping.h>
+#include <linux/platform_device.h>
+#include <linux/scatterlist.h>
+
+#include <linux/cache.h>
+#include <linux/io.h>
+
+#include <asm/octeon/octeon.h>
+#include <asm/octeon/cvmx-npi-defs.h>
+#include <asm/octeon/cvmx-pci-defs.h>
#include <dma-coherence.h>
+#ifdef CONFIG_PCI
+#include "pci-common.h"
+#endif
+
+#define BAR2_PCI_ADDRESS 0x8000000000ul
+
+struct bar1_index_state {
+ int16_t ref_count; /* Number of PCI mappings using this index */
+ uint16_t address_bits; /* Upper bits of physical address. This is
+ shifted 22 bits */
+};
+
+#ifdef CONFIG_PCI
+static DEFINE_SPINLOCK(bar1_lock);
+static struct bar1_index_state bar1_state[32];
+#endif
+
dma_addr_t octeon_map_dma_mem(struct device *dev, void *ptr, size_t size)
{
+#ifndef CONFIG_PCI
/* Without PCI/PCIe this function can be called for Octeon internal
devices such as USB. These devices all support 64bit addressing */
mb();
return virt_to_phys(ptr);
+#else
+ unsigned long flags;
+ uint64_t dma_mask;
+ int64_t start_index;
+ dma_addr_t result = -1;
+ uint64_t physical = virt_to_phys(ptr);
+ int64_t index;
+
+ mb();
+ /*
+ * Use the DMA masks to determine the allowed memory
+ * region. For us it doesn't limit the actual memory, just the
+ * address visible over PCI. Devices with limits need to use
+ * lower indexed Bar1 entries.
+ */
+ if (dev) {
+ dma_mask = dev->coherent_dma_mask;
+ if (dev->dma_mask)
+ dma_mask = *dev->dma_mask;
+ } else {
+ dma_mask = 0xfffffffful;
+ }
+
+ /*
+ * Platform devices, such as the internal USB, skip all
+ * translation and use Octeon physical addresses directly.
+ */
+ if (!dev || dev->bus == &platform_bus_type)
+ return physical;
+
+ switch (octeon_dma_bar_type) {
+ case OCTEON_DMA_BAR_TYPE_PCIE:
+ if (unlikely(physical < (16ul << 10)))
+ panic("dma_map_single: Not allowed to map first 16KB."
+ " It interferes with BAR0 special area\n");
+ else if ((physical + size >= (256ul << 20)) &&
+ (physical < (512ul << 20)))
+ panic("dma_map_single: Not allowed to map bootbus\n");
+ else if ((physical + size >= 0x400000000ull) &&
+ physical < 0x410000000ull)
+ panic("dma_map_single: "
+ "Attempt to map illegal memory address 0x%llx\n",
+ physical);
+ else if (physical >= 0x420000000ull)
+ panic("dma_map_single: "
+ "Attempt to map illegal memory address 0x%llx\n",
+ physical);
+ else if ((physical + size >=
+ (4ull<<30) - (OCTEON_PCI_BAR1_HOLE_SIZE<<20))
+ && physical < (4ull<<30))
+ pr_warning("dma_map_single: Warning: "
+ "Mapping memory address that might "
+ "conflict with devices 0x%llx-0x%llx\n",
+ physical, physical+size-1);
+ /* The 2nd 256MB is mapped at 256<<20 instead of 0x410000000 */
+ if ((physical >= 0x410000000ull) && physical < 0x420000000ull)
+ result = physical - 0x400000000ull;
+ else
+ result = physical;
+ if (((result+size-1) & dma_mask) != result+size-1)
+ panic("dma_map_single: Attempt to map address "
+ "0x%llx-0x%llx, which can't be accessed "
+ "according to the dma mask 0x%llx\n",
+ physical, physical+size-1, dma_mask);
+ goto done;
+
+ case OCTEON_DMA_BAR_TYPE_BIG:
+#ifdef CONFIG_64BIT
+ /* If the device supports 64bit addressing, then use BAR2 */
+ if (dma_mask > BAR2_PCI_ADDRESS) {
+ result = physical + BAR2_PCI_ADDRESS;
+ goto done;
+ }
+#endif
+ if (unlikely(physical < (4ul << 10))) {
+ panic("dma_map_single: Not allowed to map first 4KB. "
+ "It interferes with BAR0 special area\n");
+ } else if (physical < (256ul << 20)) {
+ if (unlikely(physical + size > (256ul << 20)))
+ panic("dma_map_single: Requested memory spans "
+ "Bar0 0:256MB and bootbus\n");
+ result = physical;
+ goto done;
+ } else if (unlikely(physical < (512ul << 20))) {
+ panic("dma_map_single: Not allowed to map bootbus\n");
+ } else if (physical < (2ul << 30)) {
+ if (unlikely(physical + size > (2ul << 30)))
+ panic("dma_map_single: Requested memory spans "
+ "Bar0 512MB:2GB and BAR1\n");
+ result = physical;
+ goto done;
+ } else if (physical < (2ul << 30) + (128 << 20)) {
+ /* Fall through */
+ } else if (physical <
+ (4ul << 30) - (OCTEON_PCI_BAR1_HOLE_SIZE << 20)) {
+ if (unlikely
+ (physical + size >
+ (4ul << 30) - (OCTEON_PCI_BAR1_HOLE_SIZE << 20)))
+ panic("dma_map_single: Requested memory "
+ "extends past Bar1 (4GB-%luMB)\n",
+ OCTEON_PCI_BAR1_HOLE_SIZE);
+ result = physical;
+ goto done;
+ } else if ((physical >= 0x410000000ull) &&
+ (physical < 0x420000000ull)) {
+ if (unlikely(physical + size > 0x420000000ull))
+ panic("dma_map_single: Requested memory spans "
+ "non existant memory\n");
+ /* BAR0 fixed mapping 256MB:512MB ->
+ * 16GB+256MB:16GB+512MB */
+ result = physical - 0x400000000ull;
+ goto done;
+ } else {
+ /* Continued below switch statement */
+ }
+ break;
+
+ case OCTEON_DMA_BAR_TYPE_SMALL:
+#ifdef CONFIG_64BIT
+ /* If the device supports 64bit addressing, then use BAR2 */
+ if (dma_mask > BAR2_PCI_ADDRESS) {
+ result = physical + BAR2_PCI_ADDRESS;
+ goto done;
+ }
+#endif
+ /* Continued below switch statement */
+ break;
+
+ default:
+ panic("dma_map_single: Invalid octeon_dma_bar_type\n");
+ }
+
+ /* Don't allow mapping to span multiple Bar entries. The hardware guys
+ won't guarantee that DMA across boards work */
+ if (unlikely((physical >> 22) != ((physical + size - 1) >> 22)))
+ panic("dma_map_single: "
+ "Requested memory spans more than one Bar1 entry\n");
+
+ if (octeon_dma_bar_type == OCTEON_DMA_BAR_TYPE_BIG)
+ start_index = 31;
+ else if (unlikely(dma_mask < (1ul << 27)))
+ start_index = (dma_mask >> 22);
+ else
+ start_index = 31;
+
+ /* Only one processor can access the Bar register at once */
+ spin_lock_irqsave(&bar1_lock, flags);
+
+ /* Look through Bar1 for existing mapping that will work */
+ for (index = start_index; index >= 0; index--) {
+ if ((bar1_state[index].address_bits == physical >> 22) &&
+ (bar1_state[index].ref_count)) {
+ /* An existing mapping will work, use it */
+ bar1_state[index].ref_count++;
+ if (unlikely(bar1_state[index].ref_count < 0))
+ panic("dma_map_single: "
+ "Bar1[%d] reference count overflowed\n",
+ (int) index);
+ result = (index << 22) | (physical & ((1 << 22) - 1));
+ /* Large BAR1 is offset at 2GB */
+ if (octeon_dma_bar_type == OCTEON_DMA_BAR_TYPE_BIG)
+ result += 2ul << 30;
+ goto done_unlock;
+ }
+ }
+
+ /* No existing mappings, look for a free entry */
+ for (index = start_index; index >= 0; index--) {
+ if (unlikely(bar1_state[index].ref_count == 0)) {
+ union cvmx_pci_bar1_indexx bar1_index;
+ /* We have a free entry, use it */
+ bar1_state[index].ref_count = 1;
+ bar1_state[index].address_bits = physical >> 22;
+ bar1_index.u32 = 0;
+ /* Address bits[35:22] sent to L2C */
+ bar1_index.s.addr_idx = physical >> 22;
+ /* Don't put PCI accesses in L2. */
+ bar1_index.s.ca = 1;
+ /* Endian Swap Mode */
+ bar1_index.s.end_swp = 1;
+ /* Set '1' when the selected address range is valid. */
+ bar1_index.s.addr_v = 1;
+ octeon_npi_write32(CVMX_NPI_PCI_BAR1_INDEXX(index),
+ bar1_index.u32);
+ /* An existing mapping will work, use it */
+ result = (index << 22) | (physical & ((1 << 22) - 1));
+ /* Large BAR1 is offset at 2GB */
+ if (octeon_dma_bar_type == OCTEON_DMA_BAR_TYPE_BIG)
+ result += 2ul << 30;
+ goto done_unlock;
+ }
+ }
+
+ pr_err("dma_map_single: "
+ "Can't find empty BAR1 index for physical mapping 0x%llx\n",
+ (unsigned long long) physical);
+
+done_unlock:
+ spin_unlock_irqrestore(&bar1_lock, flags);
+done:
+ pr_debug("dma_map_single 0x%llx->0x%llx\n", physical, result);
+ return result;
+#endif
}
void octeon_unmap_dma_mem(struct device *dev, dma_addr_t dma_addr)
{
- /* Without PCI/PCIe this function can be called for Octeon internal
- * devices such as USB. These devices all support 64bit addressing */
+#ifndef CONFIG_PCI
+ /*
+ * Without PCI/PCIe this function can be called for Octeon internal
+ * devices such as USB. These devices all support 64bit addressing.
+ */
+ return;
+#else
+ unsigned long flags;
+ uint64_t index;
+
+ /*
+ * Platform devices, such as the internal USB, skip all
+ * translation and use Octeon physical addresses directly.
+ */
+ if (dev->bus == &platform_bus_type)
+ return;
+
+ switch (octeon_dma_bar_type) {
+ case OCTEON_DMA_BAR_TYPE_PCIE:
+ /* Nothing to do, all mappings are static */
+ goto done;
+
+ case OCTEON_DMA_BAR_TYPE_BIG:
+#ifdef CONFIG_64BIT
+ /* Nothing to do for addresses using BAR2 */
+ if (dma_addr >= BAR2_PCI_ADDRESS)
+ goto done;
+#endif
+ if (unlikely(dma_addr < (4ul << 10)))
+ panic("dma_unmap_single: Unexpect DMA address 0x%llx\n",
+ dma_addr);
+ else if (dma_addr < (2ul << 30))
+ /* Nothing to do for addresses using BAR0 */
+ goto done;
+ else if (dma_addr < (2ul << 30) + (128ul << 20))
+ /* Need to unmap, fall through */
+ index = (dma_addr - (2ul << 30)) >> 22;
+ else if (dma_addr <
+ (4ul << 30) - (OCTEON_PCI_BAR1_HOLE_SIZE << 20))
+ goto done; /* Nothing to do for the rest of BAR1 */
+ else
+ panic("dma_unmap_single: Unexpect DMA address 0x%llx\n",
+ dma_addr);
+ /* Continued below switch statement */
+ break;
+
+ case OCTEON_DMA_BAR_TYPE_SMALL:
+#ifdef CONFIG_64BIT
+ /* Nothing to do for addresses using BAR2 */
+ if (dma_addr >= BAR2_PCI_ADDRESS)
+ goto done;
+#endif
+ index = dma_addr >> 22;
+ /* Continued below switch statement */
+ break;
+
+ default:
+ panic("dma_unmap_single: Invalid octeon_dma_bar_type\n");
+ }
+
+ if (unlikely(index > 31))
+ panic("dma_unmap_single: "
+ "Attempt to unmap an invalid address (0x%llx)\n",
+ dma_addr);
+
+ spin_lock_irqsave(&bar1_lock, flags);
+ bar1_state[index].ref_count--;
+ if (bar1_state[index].ref_count == 0)
+ octeon_npi_write32(CVMX_NPI_PCI_BAR1_INDEXX(index), 0);
+ else if (unlikely(bar1_state[index].ref_count < 0))
+ panic("dma_unmap_single: Bar1[%u] reference count < 0\n",
+ (int) index);
+ spin_unlock_irqrestore(&bar1_lock, flags);
+done:
+ pr_debug("dma_unmap_single 0x%llx\n", dma_addr);
return;
+#endif
}