mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-24 01:41:39 +00:00
![Cai Huoqing](/assets/img/avatar_default.png)
use SPDX-License-Identifier instead of a verbose license text Link: https://lore.kernel.org/r/20210823042622.109-1-caihuoqing@baidu.com Signed-off-by: Cai Huoqing <caihuoqing@baidu.com> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
715 lines
18 KiB
C
715 lines
18 KiB
C
// SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause
|
|
/*
|
|
* Copyright(c) 2015, 2016 Intel Corporation.
|
|
*/
|
|
|
|
#include "hfi.h"
|
|
|
|
/* additive distance between non-SOP and SOP space */
|
|
#define SOP_DISTANCE (TXE_PIO_SIZE / 2)
|
|
#define PIO_BLOCK_MASK (PIO_BLOCK_SIZE - 1)
|
|
/* number of QUADWORDs in a block */
|
|
#define PIO_BLOCK_QWS (PIO_BLOCK_SIZE / sizeof(u64))
|
|
|
|
/**
|
|
* pio_copy - copy data block to MMIO space
|
|
* @dd: hfi1 dev data
|
|
* @pbuf: a number of blocks allocated within a PIO send context
|
|
* @pbc: PBC to send
|
|
* @from: source, must be 8 byte aligned
|
|
* @count: number of DWORD (32-bit) quantities to copy from source
|
|
*
|
|
* Copy data from source to PIO Send Buffer memory, 8 bytes at a time.
|
|
* Must always write full BLOCK_SIZE bytes blocks. The first block must
|
|
* be written to the corresponding SOP=1 address.
|
|
*
|
|
* Known:
|
|
* o pbuf->start always starts on a block boundary
|
|
* o pbuf can wrap only at a block boundary
|
|
*/
|
|
void pio_copy(struct hfi1_devdata *dd, struct pio_buf *pbuf, u64 pbc,
|
|
const void *from, size_t count)
|
|
{
|
|
void __iomem *dest = pbuf->start + SOP_DISTANCE;
|
|
void __iomem *send = dest + PIO_BLOCK_SIZE;
|
|
void __iomem *dend; /* 8-byte data end */
|
|
|
|
/* write the PBC */
|
|
writeq(pbc, dest);
|
|
dest += sizeof(u64);
|
|
|
|
/* calculate where the QWORD data ends - in SOP=1 space */
|
|
dend = dest + ((count >> 1) * sizeof(u64));
|
|
|
|
if (dend < send) {
|
|
/*
|
|
* all QWORD data is within the SOP block, does *not*
|
|
* reach the end of the SOP block
|
|
*/
|
|
|
|
while (dest < dend) {
|
|
writeq(*(u64 *)from, dest);
|
|
from += sizeof(u64);
|
|
dest += sizeof(u64);
|
|
}
|
|
/*
|
|
* No boundary checks are needed here:
|
|
* 0. We're not on the SOP block boundary
|
|
* 1. The possible DWORD dangle will still be within
|
|
* the SOP block
|
|
* 2. We cannot wrap except on a block boundary.
|
|
*/
|
|
} else {
|
|
/* QWORD data extends _to_ or beyond the SOP block */
|
|
|
|
/* write 8-byte SOP chunk data */
|
|
while (dest < send) {
|
|
writeq(*(u64 *)from, dest);
|
|
from += sizeof(u64);
|
|
dest += sizeof(u64);
|
|
}
|
|
/* drop out of the SOP range */
|
|
dest -= SOP_DISTANCE;
|
|
dend -= SOP_DISTANCE;
|
|
|
|
/*
|
|
* If the wrap comes before or matches the data end,
|
|
* copy until until the wrap, then wrap.
|
|
*
|
|
* If the data ends at the end of the SOP above and
|
|
* the buffer wraps, then pbuf->end == dend == dest
|
|
* and nothing will get written, but we will wrap in
|
|
* case there is a dangling DWORD.
|
|
*/
|
|
if (pbuf->end <= dend) {
|
|
while (dest < pbuf->end) {
|
|
writeq(*(u64 *)from, dest);
|
|
from += sizeof(u64);
|
|
dest += sizeof(u64);
|
|
}
|
|
|
|
dest -= pbuf->sc->size;
|
|
dend -= pbuf->sc->size;
|
|
}
|
|
|
|
/* write 8-byte non-SOP, non-wrap chunk data */
|
|
while (dest < dend) {
|
|
writeq(*(u64 *)from, dest);
|
|
from += sizeof(u64);
|
|
dest += sizeof(u64);
|
|
}
|
|
}
|
|
/* at this point we have wrapped if we are going to wrap */
|
|
|
|
/* write dangling u32, if any */
|
|
if (count & 1) {
|
|
union mix val;
|
|
|
|
val.val64 = 0;
|
|
val.val32[0] = *(u32 *)from;
|
|
writeq(val.val64, dest);
|
|
dest += sizeof(u64);
|
|
}
|
|
/*
|
|
* fill in rest of block, no need to check pbuf->end
|
|
* as we only wrap on a block boundary
|
|
*/
|
|
while (((unsigned long)dest & PIO_BLOCK_MASK) != 0) {
|
|
writeq(0, dest);
|
|
dest += sizeof(u64);
|
|
}
|
|
|
|
/* finished with this buffer */
|
|
this_cpu_dec(*pbuf->sc->buffers_allocated);
|
|
preempt_enable();
|
|
}
|
|
|
|
/*
|
|
* Handle carry bytes using shifts and masks.
|
|
*
|
|
* NOTE: the value the unused portion of carry is expected to always be zero.
|
|
*/
|
|
|
|
/*
|
|
* "zero" shift - bit shift used to zero out upper bytes. Input is
|
|
* the count of LSB bytes to preserve.
|
|
*/
|
|
#define zshift(x) (8 * (8 - (x)))
|
|
|
|
/*
|
|
* "merge" shift - bit shift used to merge with carry bytes. Input is
|
|
* the LSB byte count to move beyond.
|
|
*/
|
|
#define mshift(x) (8 * (x))
|
|
|
|
/*
|
|
* Jump copy - no-loop copy for < 8 bytes.
|
|
*/
|
|
static inline void jcopy(u8 *dest, const u8 *src, u32 n)
|
|
{
|
|
switch (n) {
|
|
case 7:
|
|
*dest++ = *src++;
|
|
fallthrough;
|
|
case 6:
|
|
*dest++ = *src++;
|
|
fallthrough;
|
|
case 5:
|
|
*dest++ = *src++;
|
|
fallthrough;
|
|
case 4:
|
|
*dest++ = *src++;
|
|
fallthrough;
|
|
case 3:
|
|
*dest++ = *src++;
|
|
fallthrough;
|
|
case 2:
|
|
*dest++ = *src++;
|
|
fallthrough;
|
|
case 1:
|
|
*dest++ = *src++;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Read nbytes from "from" and and place them in the low bytes
|
|
* of pbuf->carry. Other bytes are left as-is. Any previous
|
|
* value in pbuf->carry is lost.
|
|
*
|
|
* NOTES:
|
|
* o do not read from from if nbytes is zero
|
|
* o from may _not_ be u64 aligned.
|
|
*/
|
|
static inline void read_low_bytes(struct pio_buf *pbuf, const void *from,
|
|
unsigned int nbytes)
|
|
{
|
|
pbuf->carry.val64 = 0;
|
|
jcopy(&pbuf->carry.val8[0], from, nbytes);
|
|
pbuf->carry_bytes = nbytes;
|
|
}
|
|
|
|
/*
|
|
* Read nbytes bytes from "from" and put them at the end of pbuf->carry.
|
|
* It is expected that the extra read does not overfill carry.
|
|
*
|
|
* NOTES:
|
|
* o from may _not_ be u64 aligned
|
|
* o nbytes may span a QW boundary
|
|
*/
|
|
static inline void read_extra_bytes(struct pio_buf *pbuf,
|
|
const void *from, unsigned int nbytes)
|
|
{
|
|
jcopy(&pbuf->carry.val8[pbuf->carry_bytes], from, nbytes);
|
|
pbuf->carry_bytes += nbytes;
|
|
}
|
|
|
|
/*
|
|
* Write a quad word using parts of pbuf->carry and the next 8 bytes of src.
|
|
* Put the unused part of the next 8 bytes of src into the LSB bytes of
|
|
* pbuf->carry with the upper bytes zeroed..
|
|
*
|
|
* NOTES:
|
|
* o result must keep unused bytes zeroed
|
|
* o src must be u64 aligned
|
|
*/
|
|
static inline void merge_write8(
|
|
struct pio_buf *pbuf,
|
|
void __iomem *dest,
|
|
const void *src)
|
|
{
|
|
u64 new, temp;
|
|
|
|
new = *(u64 *)src;
|
|
temp = pbuf->carry.val64 | (new << mshift(pbuf->carry_bytes));
|
|
writeq(temp, dest);
|
|
pbuf->carry.val64 = new >> zshift(pbuf->carry_bytes);
|
|
}
|
|
|
|
/*
|
|
* Write a quad word using all bytes of carry.
|
|
*/
|
|
static inline void carry8_write8(union mix carry, void __iomem *dest)
|
|
{
|
|
writeq(carry.val64, dest);
|
|
}
|
|
|
|
/*
|
|
* Write a quad word using all the valid bytes of carry. If carry
|
|
* has zero valid bytes, nothing is written.
|
|
* Returns 0 on nothing written, non-zero on quad word written.
|
|
*/
|
|
static inline int carry_write8(struct pio_buf *pbuf, void __iomem *dest)
|
|
{
|
|
if (pbuf->carry_bytes) {
|
|
/* unused bytes are always kept zeroed, so just write */
|
|
writeq(pbuf->carry.val64, dest);
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Segmented PIO Copy - start
|
|
*
|
|
* Start a PIO copy.
|
|
*
|
|
* @pbuf: destination buffer
|
|
* @pbc: the PBC for the PIO buffer
|
|
* @from: data source, QWORD aligned
|
|
* @nbytes: bytes to copy
|
|
*/
|
|
void seg_pio_copy_start(struct pio_buf *pbuf, u64 pbc,
|
|
const void *from, size_t nbytes)
|
|
{
|
|
void __iomem *dest = pbuf->start + SOP_DISTANCE;
|
|
void __iomem *send = dest + PIO_BLOCK_SIZE;
|
|
void __iomem *dend; /* 8-byte data end */
|
|
|
|
writeq(pbc, dest);
|
|
dest += sizeof(u64);
|
|
|
|
/* calculate where the QWORD data ends - in SOP=1 space */
|
|
dend = dest + ((nbytes >> 3) * sizeof(u64));
|
|
|
|
if (dend < send) {
|
|
/*
|
|
* all QWORD data is within the SOP block, does *not*
|
|
* reach the end of the SOP block
|
|
*/
|
|
|
|
while (dest < dend) {
|
|
writeq(*(u64 *)from, dest);
|
|
from += sizeof(u64);
|
|
dest += sizeof(u64);
|
|
}
|
|
/*
|
|
* No boundary checks are needed here:
|
|
* 0. We're not on the SOP block boundary
|
|
* 1. The possible DWORD dangle will still be within
|
|
* the SOP block
|
|
* 2. We cannot wrap except on a block boundary.
|
|
*/
|
|
} else {
|
|
/* QWORD data extends _to_ or beyond the SOP block */
|
|
|
|
/* write 8-byte SOP chunk data */
|
|
while (dest < send) {
|
|
writeq(*(u64 *)from, dest);
|
|
from += sizeof(u64);
|
|
dest += sizeof(u64);
|
|
}
|
|
/* drop out of the SOP range */
|
|
dest -= SOP_DISTANCE;
|
|
dend -= SOP_DISTANCE;
|
|
|
|
/*
|
|
* If the wrap comes before or matches the data end,
|
|
* copy until until the wrap, then wrap.
|
|
*
|
|
* If the data ends at the end of the SOP above and
|
|
* the buffer wraps, then pbuf->end == dend == dest
|
|
* and nothing will get written, but we will wrap in
|
|
* case there is a dangling DWORD.
|
|
*/
|
|
if (pbuf->end <= dend) {
|
|
while (dest < pbuf->end) {
|
|
writeq(*(u64 *)from, dest);
|
|
from += sizeof(u64);
|
|
dest += sizeof(u64);
|
|
}
|
|
|
|
dest -= pbuf->sc->size;
|
|
dend -= pbuf->sc->size;
|
|
}
|
|
|
|
/* write 8-byte non-SOP, non-wrap chunk data */
|
|
while (dest < dend) {
|
|
writeq(*(u64 *)from, dest);
|
|
from += sizeof(u64);
|
|
dest += sizeof(u64);
|
|
}
|
|
}
|
|
/* at this point we have wrapped if we are going to wrap */
|
|
|
|
/* ...but it doesn't matter as we're done writing */
|
|
|
|
/* save dangling bytes, if any */
|
|
read_low_bytes(pbuf, from, nbytes & 0x7);
|
|
|
|
pbuf->qw_written = 1 /*PBC*/ + (nbytes >> 3);
|
|
}
|
|
|
|
/*
|
|
* Mid copy helper, "mixed case" - source is 64-bit aligned but carry
|
|
* bytes are non-zero.
|
|
*
|
|
* Whole u64s must be written to the chip, so bytes must be manually merged.
|
|
*
|
|
* @pbuf: destination buffer
|
|
* @from: data source, is QWORD aligned.
|
|
* @nbytes: bytes to copy
|
|
*
|
|
* Must handle nbytes < 8.
|
|
*/
|
|
static void mid_copy_mix(struct pio_buf *pbuf, const void *from, size_t nbytes)
|
|
{
|
|
void __iomem *dest = pbuf->start + (pbuf->qw_written * sizeof(u64));
|
|
void __iomem *dend; /* 8-byte data end */
|
|
unsigned long qw_to_write = nbytes >> 3;
|
|
unsigned long bytes_left = nbytes & 0x7;
|
|
|
|
/* calculate 8-byte data end */
|
|
dend = dest + (qw_to_write * sizeof(u64));
|
|
|
|
if (pbuf->qw_written < PIO_BLOCK_QWS) {
|
|
/*
|
|
* Still within SOP block. We don't need to check for
|
|
* wrap because we are still in the first block and
|
|
* can only wrap on block boundaries.
|
|
*/
|
|
void __iomem *send; /* SOP end */
|
|
void __iomem *xend;
|
|
|
|
/*
|
|
* calculate the end of data or end of block, whichever
|
|
* comes first
|
|
*/
|
|
send = pbuf->start + PIO_BLOCK_SIZE;
|
|
xend = min(send, dend);
|
|
|
|
/* shift up to SOP=1 space */
|
|
dest += SOP_DISTANCE;
|
|
xend += SOP_DISTANCE;
|
|
|
|
/* write 8-byte chunk data */
|
|
while (dest < xend) {
|
|
merge_write8(pbuf, dest, from);
|
|
from += sizeof(u64);
|
|
dest += sizeof(u64);
|
|
}
|
|
|
|
/* shift down to SOP=0 space */
|
|
dest -= SOP_DISTANCE;
|
|
}
|
|
/*
|
|
* At this point dest could be (either, both, or neither):
|
|
* - at dend
|
|
* - at the wrap
|
|
*/
|
|
|
|
/*
|
|
* If the wrap comes before or matches the data end,
|
|
* copy until until the wrap, then wrap.
|
|
*
|
|
* If dest is at the wrap, we will fall into the if,
|
|
* not do the loop, when wrap.
|
|
*
|
|
* If the data ends at the end of the SOP above and
|
|
* the buffer wraps, then pbuf->end == dend == dest
|
|
* and nothing will get written.
|
|
*/
|
|
if (pbuf->end <= dend) {
|
|
while (dest < pbuf->end) {
|
|
merge_write8(pbuf, dest, from);
|
|
from += sizeof(u64);
|
|
dest += sizeof(u64);
|
|
}
|
|
|
|
dest -= pbuf->sc->size;
|
|
dend -= pbuf->sc->size;
|
|
}
|
|
|
|
/* write 8-byte non-SOP, non-wrap chunk data */
|
|
while (dest < dend) {
|
|
merge_write8(pbuf, dest, from);
|
|
from += sizeof(u64);
|
|
dest += sizeof(u64);
|
|
}
|
|
|
|
pbuf->qw_written += qw_to_write;
|
|
|
|
/* handle carry and left-over bytes */
|
|
if (pbuf->carry_bytes + bytes_left >= 8) {
|
|
unsigned long nread;
|
|
|
|
/* there is enough to fill another qw - fill carry */
|
|
nread = 8 - pbuf->carry_bytes;
|
|
read_extra_bytes(pbuf, from, nread);
|
|
|
|
/*
|
|
* One more write - but need to make sure dest is correct.
|
|
* Check for wrap and the possibility the write
|
|
* should be in SOP space.
|
|
*
|
|
* The two checks immediately below cannot both be true, hence
|
|
* the else. If we have wrapped, we cannot still be within the
|
|
* first block. Conversely, if we are still in the first block,
|
|
* we cannot have wrapped. We do the wrap check first as that
|
|
* is more likely.
|
|
*/
|
|
/* adjust if we have wrapped */
|
|
if (dest >= pbuf->end)
|
|
dest -= pbuf->sc->size;
|
|
/* jump to the SOP range if within the first block */
|
|
else if (pbuf->qw_written < PIO_BLOCK_QWS)
|
|
dest += SOP_DISTANCE;
|
|
|
|
/* flush out full carry */
|
|
carry8_write8(pbuf->carry, dest);
|
|
pbuf->qw_written++;
|
|
|
|
/* now adjust and read the rest of the bytes into carry */
|
|
bytes_left -= nread;
|
|
from += nread; /* from is now not aligned */
|
|
read_low_bytes(pbuf, from, bytes_left);
|
|
} else {
|
|
/* not enough to fill another qw, append the rest to carry */
|
|
read_extra_bytes(pbuf, from, bytes_left);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Mid copy helper, "straight case" - source pointer is 64-bit aligned
|
|
* with no carry bytes.
|
|
*
|
|
* @pbuf: destination buffer
|
|
* @from: data source, is QWORD aligned
|
|
* @nbytes: bytes to copy
|
|
*
|
|
* Must handle nbytes < 8.
|
|
*/
|
|
static void mid_copy_straight(struct pio_buf *pbuf,
|
|
const void *from, size_t nbytes)
|
|
{
|
|
void __iomem *dest = pbuf->start + (pbuf->qw_written * sizeof(u64));
|
|
void __iomem *dend; /* 8-byte data end */
|
|
|
|
/* calculate 8-byte data end */
|
|
dend = dest + ((nbytes >> 3) * sizeof(u64));
|
|
|
|
if (pbuf->qw_written < PIO_BLOCK_QWS) {
|
|
/*
|
|
* Still within SOP block. We don't need to check for
|
|
* wrap because we are still in the first block and
|
|
* can only wrap on block boundaries.
|
|
*/
|
|
void __iomem *send; /* SOP end */
|
|
void __iomem *xend;
|
|
|
|
/*
|
|
* calculate the end of data or end of block, whichever
|
|
* comes first
|
|
*/
|
|
send = pbuf->start + PIO_BLOCK_SIZE;
|
|
xend = min(send, dend);
|
|
|
|
/* shift up to SOP=1 space */
|
|
dest += SOP_DISTANCE;
|
|
xend += SOP_DISTANCE;
|
|
|
|
/* write 8-byte chunk data */
|
|
while (dest < xend) {
|
|
writeq(*(u64 *)from, dest);
|
|
from += sizeof(u64);
|
|
dest += sizeof(u64);
|
|
}
|
|
|
|
/* shift down to SOP=0 space */
|
|
dest -= SOP_DISTANCE;
|
|
}
|
|
/*
|
|
* At this point dest could be (either, both, or neither):
|
|
* - at dend
|
|
* - at the wrap
|
|
*/
|
|
|
|
/*
|
|
* If the wrap comes before or matches the data end,
|
|
* copy until until the wrap, then wrap.
|
|
*
|
|
* If dest is at the wrap, we will fall into the if,
|
|
* not do the loop, when wrap.
|
|
*
|
|
* If the data ends at the end of the SOP above and
|
|
* the buffer wraps, then pbuf->end == dend == dest
|
|
* and nothing will get written.
|
|
*/
|
|
if (pbuf->end <= dend) {
|
|
while (dest < pbuf->end) {
|
|
writeq(*(u64 *)from, dest);
|
|
from += sizeof(u64);
|
|
dest += sizeof(u64);
|
|
}
|
|
|
|
dest -= pbuf->sc->size;
|
|
dend -= pbuf->sc->size;
|
|
}
|
|
|
|
/* write 8-byte non-SOP, non-wrap chunk data */
|
|
while (dest < dend) {
|
|
writeq(*(u64 *)from, dest);
|
|
from += sizeof(u64);
|
|
dest += sizeof(u64);
|
|
}
|
|
|
|
/* we know carry_bytes was zero on entry to this routine */
|
|
read_low_bytes(pbuf, from, nbytes & 0x7);
|
|
|
|
pbuf->qw_written += nbytes >> 3;
|
|
}
|
|
|
|
/*
|
|
* Segmented PIO Copy - middle
|
|
*
|
|
* Must handle any aligned tail and any aligned source with any byte count.
|
|
*
|
|
* @pbuf: a number of blocks allocated within a PIO send context
|
|
* @from: data source
|
|
* @nbytes: number of bytes to copy
|
|
*/
|
|
void seg_pio_copy_mid(struct pio_buf *pbuf, const void *from, size_t nbytes)
|
|
{
|
|
unsigned long from_align = (unsigned long)from & 0x7;
|
|
|
|
if (pbuf->carry_bytes + nbytes < 8) {
|
|
/* not enough bytes to fill a QW */
|
|
read_extra_bytes(pbuf, from, nbytes);
|
|
return;
|
|
}
|
|
|
|
if (from_align) {
|
|
/* misaligned source pointer - align it */
|
|
unsigned long to_align;
|
|
|
|
/* bytes to read to align "from" */
|
|
to_align = 8 - from_align;
|
|
|
|
/*
|
|
* In the advance-to-alignment logic below, we do not need
|
|
* to check if we are using more than nbytes. This is because
|
|
* if we are here, we already know that carry+nbytes will
|
|
* fill at least one QW.
|
|
*/
|
|
if (pbuf->carry_bytes + to_align < 8) {
|
|
/* not enough align bytes to fill a QW */
|
|
read_extra_bytes(pbuf, from, to_align);
|
|
from += to_align;
|
|
nbytes -= to_align;
|
|
} else {
|
|
/* bytes to fill carry */
|
|
unsigned long to_fill = 8 - pbuf->carry_bytes;
|
|
/* bytes left over to be read */
|
|
unsigned long extra = to_align - to_fill;
|
|
void __iomem *dest;
|
|
|
|
/* fill carry... */
|
|
read_extra_bytes(pbuf, from, to_fill);
|
|
from += to_fill;
|
|
nbytes -= to_fill;
|
|
/* may not be enough valid bytes left to align */
|
|
if (extra > nbytes)
|
|
extra = nbytes;
|
|
|
|
/* ...now write carry */
|
|
dest = pbuf->start + (pbuf->qw_written * sizeof(u64));
|
|
|
|
/*
|
|
* The two checks immediately below cannot both be
|
|
* true, hence the else. If we have wrapped, we
|
|
* cannot still be within the first block.
|
|
* Conversely, if we are still in the first block, we
|
|
* cannot have wrapped. We do the wrap check first
|
|
* as that is more likely.
|
|
*/
|
|
/* adjust if we've wrapped */
|
|
if (dest >= pbuf->end)
|
|
dest -= pbuf->sc->size;
|
|
/* jump to SOP range if within the first block */
|
|
else if (pbuf->qw_written < PIO_BLOCK_QWS)
|
|
dest += SOP_DISTANCE;
|
|
|
|
carry8_write8(pbuf->carry, dest);
|
|
pbuf->qw_written++;
|
|
|
|
/* read any extra bytes to do final alignment */
|
|
/* this will overwrite anything in pbuf->carry */
|
|
read_low_bytes(pbuf, from, extra);
|
|
from += extra;
|
|
nbytes -= extra;
|
|
/*
|
|
* If no bytes are left, return early - we are done.
|
|
* NOTE: This short-circuit is *required* because
|
|
* "extra" may have been reduced in size and "from"
|
|
* is not aligned, as required when leaving this
|
|
* if block.
|
|
*/
|
|
if (nbytes == 0)
|
|
return;
|
|
}
|
|
|
|
/* at this point, from is QW aligned */
|
|
}
|
|
|
|
if (pbuf->carry_bytes)
|
|
mid_copy_mix(pbuf, from, nbytes);
|
|
else
|
|
mid_copy_straight(pbuf, from, nbytes);
|
|
}
|
|
|
|
/*
|
|
* Segmented PIO Copy - end
|
|
*
|
|
* Write any remainder (in pbuf->carry) and finish writing the whole block.
|
|
*
|
|
* @pbuf: a number of blocks allocated within a PIO send context
|
|
*/
|
|
void seg_pio_copy_end(struct pio_buf *pbuf)
|
|
{
|
|
void __iomem *dest = pbuf->start + (pbuf->qw_written * sizeof(u64));
|
|
|
|
/*
|
|
* The two checks immediately below cannot both be true, hence the
|
|
* else. If we have wrapped, we cannot still be within the first
|
|
* block. Conversely, if we are still in the first block, we
|
|
* cannot have wrapped. We do the wrap check first as that is
|
|
* more likely.
|
|
*/
|
|
/* adjust if we have wrapped */
|
|
if (dest >= pbuf->end)
|
|
dest -= pbuf->sc->size;
|
|
/* jump to the SOP range if within the first block */
|
|
else if (pbuf->qw_written < PIO_BLOCK_QWS)
|
|
dest += SOP_DISTANCE;
|
|
|
|
/* write final bytes, if any */
|
|
if (carry_write8(pbuf, dest)) {
|
|
dest += sizeof(u64);
|
|
/*
|
|
* NOTE: We do not need to recalculate whether dest needs
|
|
* SOP_DISTANCE or not.
|
|
*
|
|
* If we are in the first block and the dangle write
|
|
* keeps us in the same block, dest will need
|
|
* to retain SOP_DISTANCE in the loop below.
|
|
*
|
|
* If we are in the first block and the dangle write pushes
|
|
* us to the next block, then loop below will not run
|
|
* and dest is not used. Hence we do not need to update
|
|
* it.
|
|
*
|
|
* If we are past the first block, then SOP_DISTANCE
|
|
* was never added, so there is nothing to do.
|
|
*/
|
|
}
|
|
|
|
/* fill in rest of block */
|
|
while (((unsigned long)dest & PIO_BLOCK_MASK) != 0) {
|
|
writeq(0, dest);
|
|
dest += sizeof(u64);
|
|
}
|
|
|
|
/* finished with this buffer */
|
|
this_cpu_dec(*pbuf->sc->buffers_allocated);
|
|
preempt_enable();
|
|
}
|