/* $NetBSD: cia_dma.c,v 1.38 2024/02/09 22:08:31 andvar Exp $ */
/*-
* Copyright (c) 1997, 1998 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
* NASA Ames Research Center.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h> /* RCS ID & Copyright macro defns */
__KERNEL_RCSID(0, "$NetBSD: cia_dma.c,v 1.38 2024/02/09 22:08:31 andvar Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/device.h>
#define _ALPHA_BUS_DMA_PRIVATE
#include <sys/bus.h>
#include <uvm/uvm_extern.h>
#include <dev/pci/pcireg.h>
#include <dev/pci/pcivar.h>
#include <alpha/pci/ciareg.h>
#include <alpha/pci/ciavar.h>
static bus_dma_tag_t cia_dma_get_tag(bus_dma_tag_t, alpha_bus_t);
static int cia_bus_dmamap_create_direct(bus_dma_tag_t, bus_size_t, int,
bus_size_t, bus_size_t, int, bus_dmamap_t *);
static int cia_bus_dmamap_load_sgmap(bus_dma_tag_t, bus_dmamap_t, void *,
bus_size_t, struct proc *, int);
static int cia_bus_dmamap_load_mbuf_sgmap(bus_dma_tag_t, bus_dmamap_t,
struct mbuf *, int);
static int cia_bus_dmamap_load_uio_sgmap(bus_dma_tag_t, bus_dmamap_t,
struct uio *, int);
static int cia_bus_dmamap_load_raw_sgmap(bus_dma_tag_t, bus_dmamap_t,
bus_dma_segment_t *, int, bus_size_t, int);
static void cia_bus_dmamap_unload_sgmap(bus_dma_tag_t, bus_dmamap_t);
/*
* Direct-mapped window: 1G at 1G
*/
#define CIA_DIRECT_MAPPED_BASE (1UL*1024*1024*1024)
#define CIA_DIRECT_MAPPED_SIZE (1UL*1024*1024*1024)
/*
* SGMAP window for ISA: 8M at 8M
*/
#define CIA_SGMAP_MAPPED_LO_BASE (8UL*1024*1024)
#define CIA_SGMAP_MAPPED_LO_SIZE (8UL*1024*1024)
/*
* SGMAP window for PCI: 1G at 3G
*/
#define CIA_SGMAP_MAPPED_HI_BASE (3UL*1024*1024*1024)
#define CIA_SGMAP_MAPPED_HI_SIZE (1UL*1024*1024*1024)
/* ALCOR/ALGOR2/PYXIS have a 256-byte out-bound DMA prefetch threshold. */
#define CIA_SGMAP_PFTHRESH 256
static void cia_tlb_invalidate(void);
static void cia_broken_pyxis_tlb_invalidate(void);
static void (*cia_tlb_invalidate_fn)(void);
#define CIA_TLB_INVALIDATE() (*cia_tlb_invalidate_fn)()
struct alpha_sgmap cia_pyxis_bug_sgmap;
#define CIA_PYXIS_BUG_BASE (128UL*1024*1024)
#define CIA_PYXIS_BUG_SIZE (2UL*1024*1024)
static void
cia_dma_shutdown(void *arg)
{
struct cia_config *ccp = arg;
int i;
/*
* Restore the original values, to make the firmware happy.
*/
for (i = 0; i < 4; i++) {
REGVAL(CIA_PCI_W0BASE + (i * 0x100)) =
ccp->cc_saved_windows.wbase[i];
alpha_mb();
REGVAL(CIA_PCI_W0MASK + (i * 0x100)) =
ccp->cc_saved_windows.wmask[i];
alpha_mb();
REGVAL(CIA_PCI_T0BASE + (i * 0x100)) =
ccp->cc_saved_windows.tbase[i];
alpha_mb();
}
}
void
cia_dma_init(struct cia_config *ccp)
{
bus_addr_t tbase;
bus_dma_tag_t t;
bus_dma_tag_t t_sg_hi = NULL;
int i;
/*
* Save our configuration to restore at shutdown, just
* in case the firmware would get cranky with us.
*/
for (i = 0; i < 4; i++) {
ccp->cc_saved_windows.wbase[i] =
REGVAL(CIA_PCI_W0BASE + (i * 0x100));
ccp->cc_saved_windows.wmask[i] =
REGVAL(CIA_PCI_W0MASK + (i * 0x100));
ccp->cc_saved_windows.tbase[i] =
REGVAL(CIA_PCI_T0BASE + (i * 0x100));
}
shutdownhook_establish(cia_dma_shutdown, ccp);
/*
* If we have more than 1GB of RAM, then set up an sgmap-mapped
* DMA window for PCI. This is better than using the ISA window,
* which is pretty small and PCI devices could starve it.
*
* N.B. avail_end is "last-usable PFN + 1".
*/
if (uvm_physseg_get_avail_end(uvm_physseg_get_last()) >
atop(CIA_DIRECT_MAPPED_SIZE)) {
t = t_sg_hi = &ccp->cc_dmat_sgmap_hi;
t->_cookie = ccp;
t->_wbase = CIA_SGMAP_MAPPED_HI_BASE;
t->_wsize = CIA_SGMAP_MAPPED_HI_SIZE;
t->_next_window = NULL;
t->_boundary = 0;
t->_sgmap = &ccp->cc_sgmap_hi;
t->_pfthresh = CIA_SGMAP_PFTHRESH;
t->_get_tag = cia_dma_get_tag;
t->_dmamap_create = alpha_sgmap_dmamap_create;
t->_dmamap_destroy = alpha_sgmap_dmamap_destroy;
t->_dmamap_load = cia_bus_dmamap_load_sgmap;
t->_dmamap_load_mbuf = cia_bus_dmamap_load_mbuf_sgmap;
t->_dmamap_load_uio = cia_bus_dmamap_load_uio_sgmap;
t->_dmamap_load_raw = cia_bus_dmamap_load_raw_sgmap;
t->_dmamap_unload = cia_bus_dmamap_unload_sgmap;
t->_dmamap_sync = _bus_dmamap_sync;
t->_dmamem_alloc = _bus_dmamem_alloc;
t->_dmamem_free = _bus_dmamem_free;
t->_dmamem_map = _bus_dmamem_map;
t->_dmamem_unmap = _bus_dmamem_unmap;
t->_dmamem_mmap = _bus_dmamem_mmap;
}
/*
* Initialize the DMA tag used for direct-mapped DMA.
*/
t = &ccp->cc_dmat_direct;
t->_cookie = ccp;
t->_wbase = CIA_DIRECT_MAPPED_BASE;
t->_wsize = CIA_DIRECT_MAPPED_SIZE;
t->_next_window = t_sg_hi;
t->_boundary = 0;
t->_sgmap = NULL;
t->_get_tag = cia_dma_get_tag;
t->_dmamap_create = cia_bus_dmamap_create_direct;
t->_dmamap_destroy = _bus_dmamap_destroy;
t->_dmamap_load = _bus_dmamap_load_direct;
t->_dmamap_load_mbuf = _bus_dmamap_load_mbuf_direct;
t->_dmamap_load_uio = _bus_dmamap_load_uio_direct;
t->_dmamap_load_raw = _bus_dmamap_load_raw_direct;
t->_dmamap_unload = _bus_dmamap_unload;
t->_dmamap_sync = _bus_dmamap_sync;
t->_dmamem_alloc = _bus_dmamem_alloc;
t->_dmamem_free = _bus_dmamem_free;
t->_dmamem_map = _bus_dmamem_map;
t->_dmamem_unmap = _bus_dmamem_unmap;
t->_dmamem_mmap = _bus_dmamem_mmap;
/*
* Initialize the DMA tag used for sgmap-mapped ISA DMA.
*/
t = &ccp->cc_dmat_sgmap_lo;
t->_cookie = ccp;
t->_wbase = CIA_SGMAP_MAPPED_LO_BASE;
t->_wsize = CIA_SGMAP_MAPPED_LO_SIZE;
t->_next_window = NULL;
t->_boundary = 0;
t->_sgmap = &ccp->cc_sgmap_lo;
t->_pfthresh = CIA_SGMAP_PFTHRESH;
t->_get_tag = cia_dma_get_tag;
t->_dmamap_create = alpha_sgmap_dmamap_create;
t->_dmamap_destroy = alpha_sgmap_dmamap_destroy;
t->_dmamap_load = cia_bus_dmamap_load_sgmap;
t->_dmamap_load_mbuf = cia_bus_dmamap_load_mbuf_sgmap;
t->_dmamap_load_uio = cia_bus_dmamap_load_uio_sgmap;
t->_dmamap_load_raw = cia_bus_dmamap_load_raw_sgmap;
t->_dmamap_unload = cia_bus_dmamap_unload_sgmap;
t->_dmamap_sync = _bus_dmamap_sync;
t->_dmamem_alloc = _bus_dmamem_alloc;
t->_dmamem_free = _bus_dmamem_free;
t->_dmamem_map = _bus_dmamem_map;
t->_dmamem_unmap = _bus_dmamem_unmap;
t->_dmamem_mmap = _bus_dmamem_mmap;
/*
* The firmware will have set up window 1 as a 1G dirct-mapped
* DMA window beginning at 1G. While it's pretty safe to assume
* this is the case, we'll go ahead and program the registers
* as we expect as a belt-and-suspenders measure.
*/
REGVAL(CIA_PCI_W1BASE) = CIA_DIRECT_MAPPED_BASE | CIA_PCI_WnBASE_W_EN;
alpha_mb();
REGVAL(CIA_PCI_W1MASK) = CIA_PCI_WnMASK_1G;
alpha_mb();
REGVAL(CIA_PCI_T1BASE) = 0;
alpha_mb();
/*
* Initialize the SGMAP(s). Must align page table to at least 32k
* (hardware bug?).
*/
alpha_sgmap_init(t, &ccp->cc_sgmap_lo, "cia_sgmap_lo",
CIA_SGMAP_MAPPED_LO_BASE, 0, CIA_SGMAP_MAPPED_LO_SIZE,
sizeof(uint64_t), NULL, (32*1024));
if (t_sg_hi != NULL) {
alpha_sgmap_init(t_sg_hi, &ccp->cc_sgmap_hi, "cia_sgmap_hi",
CIA_SGMAP_MAPPED_HI_BASE, 0, CIA_SGMAP_MAPPED_HI_SIZE,
sizeof(uint64_t), NULL, (32*1024));
}
/*
* Set up window 0 as an 8MB SGMAP-mapped window
* starting at 8MB.
*/
REGVAL(CIA_PCI_W0BASE) = CIA_SGMAP_MAPPED_LO_BASE |
CIA_PCI_WnBASE_SG_EN | CIA_PCI_WnBASE_W_EN;
alpha_mb();
REGVAL(CIA_PCI_W0MASK) = CIA_PCI_WnMASK_8M;
alpha_mb();
tbase = ccp->cc_sgmap_lo.aps_ptpa >> CIA_PCI_TnBASE_SHIFT;
if ((tbase & CIA_PCI_TnBASE_MASK) != tbase)
panic("cia_dma_init: bad page table address");
REGVAL(CIA_PCI_T0BASE) = tbase;
alpha_mb();
/*
* (Maybe) set up window 3 as a 1G SGMAP-mapped window starting
* at 3G.
*/
if (t_sg_hi != NULL) {
REGVAL(CIA_PCI_W3BASE) = CIA_SGMAP_MAPPED_HI_BASE |
CIA_PCI_WnBASE_SG_EN | CIA_PCI_WnBASE_W_EN;
alpha_mb();
REGVAL(CIA_PCI_W3MASK) = CIA_PCI_WnMASK_1G;
alpha_mb();
tbase = ccp->cc_sgmap_hi.aps_ptpa >> CIA_PCI_TnBASE_SHIFT;
if ((tbase & CIA_PCI_TnBASE_MASK) != tbase)
panic("cia_dma_init: bad page table address");
REGVAL(CIA_PCI_T3BASE) = tbase;
alpha_mb();
} else {
REGVAL(CIA_PCI_W3BASE) = 0;
alpha_mb();
}
/*
* Pass 1 and 2 (i.e. revision <= 1) of the Pyxis have a
* broken scatter/gather TLB; it cannot be invalidated. To
* work around this problem, we configure window 2 as an SG
* 2M window at 128M, which we use in DMA loopback mode to
* read a spill page. This works by causing TLB misses,
* causing the old entries to be purged to make room for
* the new entries coming in for the spill page.
*/
if ((ccp->cc_flags & CCF_ISPYXIS) != 0 && ccp->cc_rev <= 1) {
uint64_t *page_table;
cia_tlb_invalidate_fn =
cia_broken_pyxis_tlb_invalidate;
alpha_sgmap_init(t, &cia_pyxis_bug_sgmap,
"pyxis_bug_sgmap", CIA_PYXIS_BUG_BASE, 0,
CIA_PYXIS_BUG_SIZE, sizeof(uint64_t), NULL,
(32*1024));
REGVAL(CIA_PCI_W2BASE) = CIA_PYXIS_BUG_BASE |
CIA_PCI_WnBASE_SG_EN | CIA_PCI_WnBASE_W_EN;
alpha_mb();
REGVAL(CIA_PCI_W2MASK) = CIA_PCI_WnMASK_2M;
alpha_mb();
tbase = cia_pyxis_bug_sgmap.aps_ptpa >>
CIA_PCI_TnBASE_SHIFT;
if ((tbase & CIA_PCI_TnBASE_MASK) != tbase)
panic("cia_dma_init: bad page table address");
REGVAL(CIA_PCI_T2BASE) = tbase;
alpha_mb();
/*
* Initialize the page table to point at the spill
* page. Leave the last entry invalid.
*/
pci_sgmap_pte64_init_spill_page_pte();
for (i = 0, page_table = cia_pyxis_bug_sgmap.aps_pt;
i < (CIA_PYXIS_BUG_SIZE / PAGE_SIZE) - 1; i++) {
page_table[i] =
pci_sgmap_pte64_prefetch_spill_page_pte;
}
alpha_mb();
} else {
REGVAL(CIA_PCI_W2BASE) = 0;
alpha_mb();
cia_tlb_invalidate_fn = cia_tlb_invalidate;
}
CIA_TLB_INVALIDATE();
}
/*
* Return the bus dma tag to be used for the specified bus type.
* INTERNAL USE ONLY!
*/
static bus_dma_tag_t
cia_dma_get_tag(bus_dma_tag_t t, alpha_bus_t bustype)
{
struct cia_config *ccp = t->_cookie;
switch (bustype) {
case ALPHA_BUS_PCI:
case ALPHA_BUS_EISA:
/*
* Regardless if how much memory is installed,
* start with the direct-mapped window. It will
* fall back to the SGMAP window if we encounter a
* page that is out of range.
*/
return (&ccp->cc_dmat_direct);
case ALPHA_BUS_ISA:
/*
* ISA doesn't have enough address bits to use
* the direct-mapped DMA window, so we must use
* SGMAPs.
*/
return (&ccp->cc_dmat_sgmap_lo);
default:
panic("cia_dma_get_tag: shouldn't be here, really...");
}
}
/*
* Create a CIA direct-mapped DMA map.
*/
static int
cia_bus_dmamap_create_direct(
bus_dma_tag_t t,
bus_size_t size,
int nsegments,
bus_size_t maxsegsz,
bus_size_t boundary,
int flags,
bus_dmamap_t *dmamp)
{
struct cia_config *ccp = t->_cookie;
bus_dmamap_t map;
int error;
error = _bus_dmamap_create(t, size, nsegments, maxsegsz,
boundary, flags, dmamp);
if (error)
return (error);
map = *dmamp;
if ((ccp->cc_flags & CCF_PYXISBUG) != 0 &&
map->_dm_segcnt > 1) {
/*
* We have a Pyxis with the DMA page crossing bug, make
* sure we don't coalesce adjacent DMA segments.
*
* NOTE: We can only do this if the max segment count
* is greater than 1. This is because many network
* drivers allocate large contiguous blocks of memory
* for control data structures, even though they won't
* do any single DMA that crosses a page boundary.
* --
[email protected], 2/5/2000
*/
map->_dm_flags |= DMAMAP_NO_COALESCE;
}
return (0);
}
/*
* Load a CIA SGMAP-mapped DMA map with a linear buffer.
*/
static int
cia_bus_dmamap_load_sgmap(bus_dma_tag_t t, bus_dmamap_t map, void *buf,
bus_size_t buflen, struct proc *p, int flags)
{
int error;
error = pci_sgmap_pte64_load(t, map, buf, buflen, p, flags,
t->_sgmap);
if (error == 0)
CIA_TLB_INVALIDATE();
return (error);
}
/*
* Load a CIA SGMAP-mapped DMA map with an mbuf chain.
*/
static int
cia_bus_dmamap_load_mbuf_sgmap(bus_dma_tag_t t, bus_dmamap_t map,
struct mbuf *m, int flags)
{
int error;
error = pci_sgmap_pte64_load_mbuf(t, map, m, flags, t->_sgmap);
if (error == 0)
CIA_TLB_INVALIDATE();
return (error);
}
/*
* Load a CIA SGMAP-mapped DMA map with a uio.
*/
static int
cia_bus_dmamap_load_uio_sgmap(bus_dma_tag_t t, bus_dmamap_t map,
struct uio *uio, int flags)
{
int error;
error = pci_sgmap_pte64_load_uio(t, map, uio, flags, t->_sgmap);
if (error == 0)
CIA_TLB_INVALIDATE();
return (error);
}
/*
* Load a CIA SGMAP-mapped DMA map with raw memory.
*/
static int
cia_bus_dmamap_load_raw_sgmap(bus_dma_tag_t t, bus_dmamap_t map,
bus_dma_segment_t *segs, int nsegs, bus_size_t size, int flags)
{
int error;
error = pci_sgmap_pte64_load_raw(t, map, segs, nsegs, size, flags,
t->_sgmap);
if (error == 0)
CIA_TLB_INVALIDATE();
return (error);
}
/*
* Unload a CIA DMA map.
*/
static void
cia_bus_dmamap_unload_sgmap(bus_dma_tag_t t, bus_dmamap_t map)
{
/*
* Invalidate any SGMAP page table entries used by this
* mapping.
*/
pci_sgmap_pte64_unload(t, map, t->_sgmap);
CIA_TLB_INVALIDATE();
/*
* Do the generic bits of the unload.
*/
_bus_dmamap_unload_common(t, map);
}
/*
* Flush the CIA scatter/gather TLB.
*/
static void
cia_tlb_invalidate(void)
{
alpha_mb();
REGVAL(CIA_PCI_TBIA) = CIA_PCI_TBIA_ALL;
alpha_mb();
}
/*
* Flush the scatter/gather TLB on broken Pyxis chips.
*/
static void
cia_broken_pyxis_tlb_invalidate(void)
{
uint32_t ctrl;
int i, s;
s = splhigh();
/*
* Put the Pyxis into PCI loopback mode.
*/
alpha_mb();
ctrl = REGVAL(CIA_CSR_CTRL);
REGVAL(CIA_CSR_CTRL) = ctrl | CTRL_PCI_LOOP_EN;
alpha_mb();
/*
* Now, read from PCI dense memory space at offset 128M (our
* target window base), skipping 64k on each read. This forces
* S/G TLB misses.
*
* XXX Looks like the TLB entries are `not quite LRU'. We need
* XXX to read more times than there are actual tags!
*/
for (i = 0; i < CIA_TLB_NTAGS + 4; i++) {
volatile uint64_t dummy;
dummy = *((volatile uint64_t *)
ALPHA_PHYS_TO_K0SEG(CIA_PCI_DENSE + CIA_PYXIS_BUG_BASE +
(i * 65536)));
__USE(dummy);
}
/*
* Restore normal PCI operation.
*/
alpha_mb();
REGVAL(CIA_CSR_CTRL) = ctrl;
alpha_mb();
splx(s);
}