[TG3]: Refine DMA boundary setting.

Extract DMA boundary bit selection into a seperate
function, tg3_calc_dma_bndry().  Call this from
tg3_test_dma().

Make DMA test more reliable by using no DMA boundry
setting during the test.  If the test passes, then
use the setting we selected before the test.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Michael Chan <mchan@broadcom.com>

diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c
index 3df5b78d2693752be2be36ae63613bb9fe3ea5c9..4ab9680ffbd23bf804c4427650832763f084dfba 100644 (file)
--- a/drivers/net/tg3.c
+++ b/drivers/net/tg3.c
@@ -8775,6 +8775,146 @@ static int __devinit tg3_get_device_address(struct tg3 *tp)
        return 0;
 }
 
+#define BOUNDARY_SINGLE_CACHELINE      1
+#define BOUNDARY_MULTI_CACHELINE       2
+
+static u32 __devinit tg3_calc_dma_bndry(struct tg3 *tp, u32 val)
+{
+       int cacheline_size;
+       u8 byte;
+       int goal;
+
+       pci_read_config_byte(tp->pdev, PCI_CACHE_LINE_SIZE, &byte);
+       if (byte == 0)
+               cacheline_size = 1024;
+       else
+               cacheline_size = (int) byte * 4;
+
+       /* On 5703 and later chips, the boundary bits have no
+        * effect.
+        */
+       if (GET_ASIC_REV(tp->pci_chip_rev_id) != ASIC_REV_5700 &&
+           GET_ASIC_REV(tp->pci_chip_rev_id) != ASIC_REV_5701 &&
+           !(tp->tg3_flags2 & TG3_FLG2_PCI_EXPRESS))
+               goto out;
+
+#if defined(CONFIG_PPC64) || defined(CONFIG_IA64) || defined(CONFIG_PARISC)
+       goal = BOUNDARY_MULTI_CACHELINE;
+#else
+#if defined(CONFIG_SPARC64) || defined(CONFIG_ALPHA)
+       goal = BOUNDARY_SINGLE_CACHELINE;
+#else
+       goal = 0;
+#endif
+#endif
+
+       if (!goal)
+               goto out;
+
+       /* PCI controllers on most RISC systems tend to disconnect
+        * when a device tries to burst across a cache-line boundary.
+        * Therefore, letting tg3 do so just wastes PCI bandwidth.
+        *
+        * Unfortunately, for PCI-E there are only limited
+        * write-side controls for this, and thus for reads
+        * we will still get the disconnects.  We'll also waste
+        * these PCI cycles for both read and write for chips
+        * other than 5700 and 5701 which do not implement the
+        * boundary bits.
+        */
+       if ((tp->tg3_flags & TG3_FLAG_PCIX_MODE) &&
+           !(tp->tg3_flags2 & TG3_FLG2_PCI_EXPRESS)) {
+               switch (cacheline_size) {
+               case 16:
+               case 32:
+               case 64:
+               case 128:
+                       if (goal == BOUNDARY_SINGLE_CACHELINE) {
+                               val |= (DMA_RWCTRL_READ_BNDRY_128_PCIX |
+                                       DMA_RWCTRL_WRITE_BNDRY_128_PCIX);
+                       } else {
+                               val |= (DMA_RWCTRL_READ_BNDRY_384_PCIX |
+                                       DMA_RWCTRL_WRITE_BNDRY_384_PCIX);
+                       }
+                       break;
+
+               case 256:
+                       val |= (DMA_RWCTRL_READ_BNDRY_256_PCIX |
+                               DMA_RWCTRL_WRITE_BNDRY_256_PCIX);
+                       break;
+
+               default:
+                       val |= (DMA_RWCTRL_READ_BNDRY_384_PCIX |
+                               DMA_RWCTRL_WRITE_BNDRY_384_PCIX);
+                       break;
+               };
+       } else if (tp->tg3_flags2 & TG3_FLG2_PCI_EXPRESS) {
+               switch (cacheline_size) {
+               case 16:
+               case 32:
+               case 64:
+                       if (goal == BOUNDARY_SINGLE_CACHELINE) {
+                               val &= ~DMA_RWCTRL_WRITE_BNDRY_DISAB_PCIE;
+                               val |= DMA_RWCTRL_WRITE_BNDRY_64_PCIE;
+                               break;
+                       }
+                       /* fallthrough */
+               case 128:
+               default:
+                       val &= ~DMA_RWCTRL_WRITE_BNDRY_DISAB_PCIE;
+                       val |= DMA_RWCTRL_WRITE_BNDRY_128_PCIE;
+                       break;
+               };
+       } else {
+               switch (cacheline_size) {
+               case 16:
+                       if (goal == BOUNDARY_SINGLE_CACHELINE) {
+                               val |= (DMA_RWCTRL_READ_BNDRY_16 |
+                                       DMA_RWCTRL_WRITE_BNDRY_16);
+                               break;
+                       }
+                       /* fallthrough */
+               case 32:
+                       if (goal == BOUNDARY_SINGLE_CACHELINE) {
+                               val |= (DMA_RWCTRL_READ_BNDRY_32 |
+                                       DMA_RWCTRL_WRITE_BNDRY_32);
+                               break;
+                       }
+                       /* fallthrough */
+               case 64:
+                       if (goal == BOUNDARY_SINGLE_CACHELINE) {
+                               val |= (DMA_RWCTRL_READ_BNDRY_64 |
+                                       DMA_RWCTRL_WRITE_BNDRY_64);
+                               break;
+                       }
+                       /* fallthrough */
+               case 128:
+                       if (goal == BOUNDARY_SINGLE_CACHELINE) {
+                               val |= (DMA_RWCTRL_READ_BNDRY_128 |
+                                       DMA_RWCTRL_WRITE_BNDRY_128);
+                               break;
+                       }
+                       /* fallthrough */
+               case 256:
+                       val |= (DMA_RWCTRL_READ_BNDRY_256 |
+                               DMA_RWCTRL_WRITE_BNDRY_256);
+                       break;
+               case 512:
+                       val |= (DMA_RWCTRL_READ_BNDRY_512 |
+                               DMA_RWCTRL_WRITE_BNDRY_512);
+                       break;
+               case 1024:
+               default:
+                       val |= (DMA_RWCTRL_READ_BNDRY_1024 |
+                               DMA_RWCTRL_WRITE_BNDRY_1024);
+                       break;
+               };
+       }
+
+out:
+       return val;
+}
+
 static int __devinit tg3_do_test_dma(struct tg3 *tp, u32 *buf, dma_addr_t buf_dma, int size, int to_device)
 {
        struct tg3_internal_buffer_desc test_desc;
@@ -8861,7 +9001,7 @@ static int __devinit tg3_do_test_dma(struct tg3 *tp, u32 *buf, dma_addr_t buf_dm
 static int __devinit tg3_test_dma(struct tg3 *tp)
 {
        dma_addr_t buf_dma;
-       u32 *buf;
+       u32 *buf, saved_dma_rwctrl;
        int ret;
 
        buf = pci_alloc_consistent(tp->pdev, TEST_BUFFER_SIZE, &buf_dma);
@@ -8873,46 +9013,7 @@ static int __devinit tg3_test_dma(struct tg3 *tp)
        tp->dma_rwctrl = ((0x7 << DMA_RWCTRL_PCI_WRITE_CMD_SHIFT) |
                          (0x6 << DMA_RWCTRL_PCI_READ_CMD_SHIFT));
 
-#ifndef CONFIG_X86
-       {
-               u8 byte;
-               int cacheline_size;
-               pci_read_config_byte(tp->pdev, PCI_CACHE_LINE_SIZE, &byte);
-
-               if (byte == 0)
-                       cacheline_size = 1024;
-               else
-                       cacheline_size = (int) byte * 4;
-
-               switch (cacheline_size) {
-               case 16:
-               case 32:
-               case 64:
-               case 128:
-                       if ((tp->tg3_flags & TG3_FLAG_PCIX_MODE) &&
-                           !(tp->tg3_flags2 & TG3_FLG2_PCI_EXPRESS)) {
-                               tp->dma_rwctrl |=
-                                       DMA_RWCTRL_WRITE_BNDRY_384_PCIX;
-                               break;
-                       } else if (tp->tg3_flags2 & TG3_FLG2_PCI_EXPRESS) {
-                               tp->dma_rwctrl &=
-                                       ~(DMA_RWCTRL_PCI_WRITE_CMD);
-                               tp->dma_rwctrl |=
-                                       DMA_RWCTRL_WRITE_BNDRY_128_PCIE;
-                               break;
-                       }
-                       /* fallthrough */
-               case 256:
-                       if (!(tp->tg3_flags & TG3_FLAG_PCIX_MODE) &&
-                           !(tp->tg3_flags2 & TG3_FLG2_PCI_EXPRESS))
-                               tp->dma_rwctrl |=
-                                       DMA_RWCTRL_WRITE_BNDRY_256;
-                       else if (!(tp->tg3_flags2 & TG3_FLG2_PCI_EXPRESS))
-                               tp->dma_rwctrl |=
-                                       DMA_RWCTRL_WRITE_BNDRY_256_PCIX;
-               };
-       }
-#endif
+       tp->dma_rwctrl = tg3_calc_dma_bndry(tp, tp->dma_rwctrl);
 
        if (tp->tg3_flags2 & TG3_FLG2_PCI_EXPRESS) {
                /* DMA read watermark not used on PCIE */
@@ -8931,7 +9032,7 @@ static int __devinit tg3_test_dma(struct tg3 *tp)
                        if (ccval == 0x6 || ccval == 0x7)
                                tp->dma_rwctrl |= DMA_RWCTRL_ONE_DMA;
 
-                       /* Set bit 23 to renable PCIX hw bug fix */
+                       /* Set bit 23 to enable PCIX hw bug fix */
                        tp->dma_rwctrl |= 0x009f0000;
                } else {
                        tp->dma_rwctrl |= 0x001b000f;
@@ -8972,6 +9073,13 @@ static int __devinit tg3_test_dma(struct tg3 *tp)
            GET_ASIC_REV(tp->pci_chip_rev_id) != ASIC_REV_5701)
                goto out;
 
+       /* It is best to perform DMA test with maximum write burst size
+        * to expose the 5700/5701 write DMA bug.
+        */
+       saved_dma_rwctrl = tp->dma_rwctrl;
+       tp->dma_rwctrl &= ~DMA_RWCTRL_WRITE_BNDRY_MASK;
+       tw32(TG3PCI_DMA_RW_CTRL, tp->dma_rwctrl);
+
        while (1) {
                u32 *p = buf, i;
 
@@ -9010,8 +9118,9 @@ static int __devinit tg3_test_dma(struct tg3 *tp)
                        if (p[i] == i)
                                continue;
 
-                       if ((tp->dma_rwctrl & DMA_RWCTRL_WRITE_BNDRY_MASK) ==
-                           DMA_RWCTRL_WRITE_BNDRY_DISAB) {
+                       if ((tp->dma_rwctrl & DMA_RWCTRL_WRITE_BNDRY_MASK) !=
+                           DMA_RWCTRL_WRITE_BNDRY_16) {
+                               tp->dma_rwctrl &= ~DMA_RWCTRL_WRITE_BNDRY_MASK;
                                tp->dma_rwctrl |= DMA_RWCTRL_WRITE_BNDRY_16;
                                tw32(TG3PCI_DMA_RW_CTRL, tp->dma_rwctrl);
                                break;
@@ -9028,6 +9137,14 @@ static int __devinit tg3_test_dma(struct tg3 *tp)
                        break;
                }
        }
+       if ((tp->dma_rwctrl & DMA_RWCTRL_WRITE_BNDRY_MASK) !=
+           DMA_RWCTRL_WRITE_BNDRY_16) {
+               /* DMA test passed without adjusting DMA boundary,
+                * just restore the calculated DMA boundary
+                */
+               tp->dma_rwctrl = saved_dma_rwctrl;
+               tw32(TG3PCI_DMA_RW_CTRL, tp->dma_rwctrl);
+       }
 
 out:
        pci_free_consistent(tp->pdev, TEST_BUFFER_SIZE, buf, buf_dma);
@@ -9429,6 +9546,8 @@ static int __devinit tg3_init_one(struct pci_dev *pdev,
               (tp->tg3_flags & TG3_FLAG_SPLIT_MODE) != 0,
               (tp->tg3_flags2 & TG3_FLG2_NO_ETH_WIRE_SPEED) == 0,
               (tp->tg3_flags2 & TG3_FLG2_TSO_CAPABLE) != 0);
+       printk(KERN_INFO "%s: dma_rwctrl[%08x]\n",
+              dev->name, tp->dma_rwctrl);
 
        return 0;