tree c4fa3bbc3a0f1bd6a146e8ec1918c2076f8d5730
parent 088dd1f81b3577c17c4c4381696bf2105ea0e43a
author David S. Miller <[EMAIL PROTECTED]> Tue, 05 Jul 2005 03:26:04 -0700
committer David S. Miller <[EMAIL PROTECTED]> Tue, 05 Jul 2005 03:26:04 -0700

[SPARC64]: Do proper DMA IRQ syncing on Tomatillo

This was the main impetus behind adding the PCI IRQ shim.

In order to properly order DMA writes wrt. interrupts, you have to
write to a PCI controller register, then poll for that bit clearing.
There is one bit for each interrupt source, and setting this register
bit tells Tomatillo to drain all pending DMA from that device.

Furthermore, Tomatillo's with revision less than 4 require us to do a
block store due to some memory transaction ordering issues it has on
JBUS.

Signed-off-by: David S. Miller <[EMAIL PROTECTED]>

 arch/sparc64/kernel/pci_schizo.c |   51 +++++++++++++++++++++++++++++++++++++++
 include/asm-sparc64/pbm.h        |    3 ++
 2 files changed, 54 insertions(+)

diff --git a/arch/sparc64/kernel/pci_schizo.c b/arch/sparc64/kernel/pci_schizo.c
--- a/arch/sparc64/kernel/pci_schizo.c
+++ b/arch/sparc64/kernel/pci_schizo.c
@@ -15,6 +15,7 @@
 #include <asm/iommu.h>
 #include <asm/irq.h>
 #include <asm/upa.h>
+#include <asm/pstate.h>
 
 #include "pci_impl.h"
 #include "iommu_common.h"
@@ -326,6 +327,44 @@ static int __init schizo_ino_to_pil(stru
        return ret;
 }
 
+static void tomatillo_wsync_handler(struct ino_bucket *bucket, void *_arg1, 
void *_arg2)
+{
+       unsigned long sync_reg = (unsigned long) _arg2;
+       u64 mask = 1 << (__irq_ino(__irq(bucket)) & IMAP_INO);
+       u64 val;
+       int limit;
+
+       schizo_write(sync_reg, mask);
+
+       limit = 100000;
+       val = 0;
+       while (--limit) {
+               val = schizo_read(sync_reg);
+               if (!(val & mask))
+                       break;
+       }
+       if (limit <= 0) {
+               printk("tomatillo_wsync_handler: DMA won't sync [%lx:%lx]\n",
+                      val, mask);
+       }
+
+       if (_arg1) {
+               static unsigned char cacheline[64]
+                       __attribute__ ((aligned (64)));
+
+               __asm__ __volatile__("rd %%fprs, %0\n\t"
+                                    "or %0, %4, %1\n\t"
+                                    "wr %1, 0x0, %%fprs\n\t"
+                                    "stda %%f0, [%5] %6\n\t"
+                                    "wr %0, 0x0, %%fprs\n\t"
+                                    "membar #Sync"
+                                    : "=&r" (mask), "=&r" (val)
+                                    : "0" (mask), "1" (val),
+                                    "i" (FPRS_FEF), "r" (&cacheline[0]),
+                                    "i" (ASI_BLK_COMMIT_P));
+       }
+}
+
 static unsigned int schizo_irq_build(struct pci_pbm_info *pbm,
                                     struct pci_dev *pdev,
                                     unsigned int ino)
@@ -369,6 +408,15 @@ static unsigned int schizo_irq_build(str
        bucket = __bucket(build_irq(pil, ign_fixup, iclr, imap));
        bucket->flags |= IBF_PCI;
 
+       if (pdev && pbm->chip_type == PBM_CHIP_TYPE_TOMATILLO) {
+               struct irq_desc *p = bucket->irq_info;
+
+               p->pre_handler = tomatillo_wsync_handler;
+               p->pre_handler_arg1 = ((pbm->chip_version <= 4) ?
+                                      (void *) 1 : (void *) 0);
+               p->pre_handler_arg2 = (void *) pbm->sync_reg;
+       }
+
        return __irq(bucket);
 }
 
@@ -2015,6 +2063,9 @@ static void __init schizo_pbm_init(struc
        pbm->pbm_regs = pr_regs[0].phys_addr;
        pbm->controller_regs = pr_regs[1].phys_addr - 0x10000UL;
 
+       if (chip_type == PBM_CHIP_TYPE_TOMATILLO)
+               pbm->sync_reg = pr_regs[3].phys_addr + 0x1a18UL;
+
        sprintf(pbm->name,
                (chip_type == PBM_CHIP_TYPE_TOMATILLO ?
                 "TOMATILLO%d PBM%c" :
diff --git a/include/asm-sparc64/pbm.h b/include/asm-sparc64/pbm.h
--- a/include/asm-sparc64/pbm.h
+++ b/include/asm-sparc64/pbm.h
@@ -145,6 +145,9 @@ struct pci_pbm_info {
        /* Physical address base of PBM registers. */
        unsigned long                   pbm_regs;
 
+       /* Physical address of DMA sync register, if any.  */
+       unsigned long                   sync_reg;
+
        /* Opaque 32-bit system bus Port ID. */
        u32                             portid;
 
-
To unsubscribe from this list: send the line "unsubscribe bk-commits-head" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to