From bb6743f4f0aed5c1f09fa77cd8d3973c31792f4f Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Mon, 4 Jul 2005 13:26:04 -0700 Subject: [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 --- arch/sparc64/kernel/pci_schizo.c | 51 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) (limited to 'arch') diff --git a/arch/sparc64/kernel/pci_schizo.c b/arch/sparc64/kernel/pci_schizo.c index 5753175b94e6..68b1a63a178c 100644 --- a/arch/sparc64/kernel/pci_schizo.c +++ b/arch/sparc64/kernel/pci_schizo.c @@ -15,6 +15,7 @@ #include #include #include +#include #include "pci_impl.h" #include "iommu_common.h" @@ -326,6 +327,44 @@ static int __init schizo_ino_to_pil(struct pci_dev *pdev, unsigned int ino) 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(struct pci_pbm_info *pbm, 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(struct pci_controller_info *p, 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" : -- cgit v1.2.3