From: "Edgar E. Iglesias" <edgar.iglesias@xilinx.com>
Reorganize the descriptor handling so that CUR_DSCR always
points to the next descriptor to be processed.
Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
---
hw/dma/xlnx-zdma.c | 47 ++++++++++++++++++++++------------------------
1 file changed, 22 insertions(+), 25 deletions(-)
diff --git a/hw/dma/xlnx-zdma.c b/hw/dma/xlnx-zdma.c
index e856d233f2..1c45367f3c 100644
--- a/hw/dma/xlnx-zdma.c
+++ b/hw/dma/xlnx-zdma.c
@@ -333,10 +333,28 @@ static void zdma_load_src_descriptor(XlnxZDMA *s)
}
}
+static void zdma_update_descr_addr(XlnxZDMA *s, bool type,
+ unsigned int basereg)
+{
+ uint64_t addr, next;
+
+ if (type == DTYPE_LINEAR) {
+ addr = zdma_get_regaddr64(s, basereg);
+ next = addr + sizeof(s->dsc_dst);
+ } else {
+ addr = zdma_get_regaddr64(s, basereg);
+ addr += sizeof(s->dsc_dst);
+ address_space_read(s->dma_as, addr, s->attr, (void *) &next, 8);
+ }
+
+ zdma_put_regaddr64(s, basereg, next);
+}
+
static void zdma_load_dst_descriptor(XlnxZDMA *s)
{
uint64_t dst_addr;
unsigned int ptype = ARRAY_FIELD_EX32(s->regs, ZDMA_CH_CTRL0, POINT_TYPE);
+ bool dst_type;
if (ptype == PT_REG) {
memcpy(&s->dsc_dst, &s->regs[R_ZDMA_CH_DST_DSCR_WORD0],
@@ -349,24 +367,10 @@ static void zdma_load_dst_descriptor(XlnxZDMA *s)
if (!zdma_load_descriptor(s, dst_addr, &s->dsc_dst)) {
ARRAY_FIELD_DP32(s->regs, ZDMA_CH_ISR, AXI_RD_DST_DSCR, true);
}
-}
-
-static uint64_t zdma_update_descr_addr(XlnxZDMA *s, bool type,
- unsigned int basereg)
-{
- uint64_t addr, next;
- if (type == DTYPE_LINEAR) {
- next = zdma_get_regaddr64(s, basereg);
- next += sizeof(s->dsc_dst);
- zdma_put_regaddr64(s, basereg, next);
- } else {
- addr = zdma_get_regaddr64(s, basereg);
- addr += sizeof(s->dsc_dst);
- address_space_read(s->dma_as, addr, s->attr, &next, 8);
- zdma_put_regaddr64(s, basereg, next);
- }
- return next;
+ /* Advance the descriptor pointer. */
+ dst_type = FIELD_EX32(s->dsc_dst.words[3], ZDMA_CH_DST_DSCR_WORD3, TYPE);
+ zdma_update_descr_addr(s, dst_type, R_ZDMA_CH_DST_CUR_DSCR_LSB);
}
static void zdma_write_dst(XlnxZDMA *s, uint8_t *buf, uint32_t len)
@@ -387,14 +391,7 @@ static void zdma_write_dst(XlnxZDMA *s, uint8_t *buf, uint32_t len)
dst_size = FIELD_EX32(s->dsc_dst.words[2], ZDMA_CH_DST_DSCR_WORD2,
SIZE);
if (dst_size == 0 && ptype == PT_MEM) {
- uint64_t next;
- bool dst_type = FIELD_EX32(s->dsc_dst.words[3],
- ZDMA_CH_DST_DSCR_WORD3,
- TYPE);
-
- next = zdma_update_descr_addr(s, dst_type,
- R_ZDMA_CH_DST_CUR_DSCR_LSB);
- zdma_load_descriptor(s, next, &s->dsc_dst);
+ zdma_load_dst_descriptor(s);
dst_size = FIELD_EX32(s->dsc_dst.words[2], ZDMA_CH_DST_DSCR_WORD2,
SIZE);
}
--
2.20.1
On Thu, Apr 2, 2020 at 6:50 AM Edgar E. Iglesias
<edgar.iglesias@gmail.com> wrote:
>
> From: "Edgar E. Iglesias" <edgar.iglesias@xilinx.com>
>
> Reorganize the descriptor handling so that CUR_DSCR always
> points to the next descriptor to be processed.
>
> Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Alistair
> ---
> hw/dma/xlnx-zdma.c | 47 ++++++++++++++++++++++------------------------
> 1 file changed, 22 insertions(+), 25 deletions(-)
>
> diff --git a/hw/dma/xlnx-zdma.c b/hw/dma/xlnx-zdma.c
> index e856d233f2..1c45367f3c 100644
> --- a/hw/dma/xlnx-zdma.c
> +++ b/hw/dma/xlnx-zdma.c
> @@ -333,10 +333,28 @@ static void zdma_load_src_descriptor(XlnxZDMA *s)
> }
> }
>
> +static void zdma_update_descr_addr(XlnxZDMA *s, bool type,
> + unsigned int basereg)
> +{
> + uint64_t addr, next;
> +
> + if (type == DTYPE_LINEAR) {
> + addr = zdma_get_regaddr64(s, basereg);
> + next = addr + sizeof(s->dsc_dst);
> + } else {
> + addr = zdma_get_regaddr64(s, basereg);
> + addr += sizeof(s->dsc_dst);
> + address_space_read(s->dma_as, addr, s->attr, (void *) &next, 8);
> + }
> +
> + zdma_put_regaddr64(s, basereg, next);
> +}
> +
> static void zdma_load_dst_descriptor(XlnxZDMA *s)
> {
> uint64_t dst_addr;
> unsigned int ptype = ARRAY_FIELD_EX32(s->regs, ZDMA_CH_CTRL0, POINT_TYPE);
> + bool dst_type;
>
> if (ptype == PT_REG) {
> memcpy(&s->dsc_dst, &s->regs[R_ZDMA_CH_DST_DSCR_WORD0],
> @@ -349,24 +367,10 @@ static void zdma_load_dst_descriptor(XlnxZDMA *s)
> if (!zdma_load_descriptor(s, dst_addr, &s->dsc_dst)) {
> ARRAY_FIELD_DP32(s->regs, ZDMA_CH_ISR, AXI_RD_DST_DSCR, true);
> }
> -}
> -
> -static uint64_t zdma_update_descr_addr(XlnxZDMA *s, bool type,
> - unsigned int basereg)
> -{
> - uint64_t addr, next;
>
> - if (type == DTYPE_LINEAR) {
> - next = zdma_get_regaddr64(s, basereg);
> - next += sizeof(s->dsc_dst);
> - zdma_put_regaddr64(s, basereg, next);
> - } else {
> - addr = zdma_get_regaddr64(s, basereg);
> - addr += sizeof(s->dsc_dst);
> - address_space_read(s->dma_as, addr, s->attr, &next, 8);
> - zdma_put_regaddr64(s, basereg, next);
> - }
> - return next;
> + /* Advance the descriptor pointer. */
> + dst_type = FIELD_EX32(s->dsc_dst.words[3], ZDMA_CH_DST_DSCR_WORD3, TYPE);
> + zdma_update_descr_addr(s, dst_type, R_ZDMA_CH_DST_CUR_DSCR_LSB);
> }
>
> static void zdma_write_dst(XlnxZDMA *s, uint8_t *buf, uint32_t len)
> @@ -387,14 +391,7 @@ static void zdma_write_dst(XlnxZDMA *s, uint8_t *buf, uint32_t len)
> dst_size = FIELD_EX32(s->dsc_dst.words[2], ZDMA_CH_DST_DSCR_WORD2,
> SIZE);
> if (dst_size == 0 && ptype == PT_MEM) {
> - uint64_t next;
> - bool dst_type = FIELD_EX32(s->dsc_dst.words[3],
> - ZDMA_CH_DST_DSCR_WORD3,
> - TYPE);
> -
> - next = zdma_update_descr_addr(s, dst_type,
> - R_ZDMA_CH_DST_CUR_DSCR_LSB);
> - zdma_load_descriptor(s, next, &s->dsc_dst);
> + zdma_load_dst_descriptor(s);
> dst_size = FIELD_EX32(s->dsc_dst.words[2], ZDMA_CH_DST_DSCR_WORD2,
> SIZE);
> }
> --
> 2.20.1
>
>
On [2020 Apr 02] Thu 15:47:21, Edgar E. Iglesias wrote:
> From: "Edgar E. Iglesias" <edgar.iglesias@xilinx.com>
>
> Reorganize the descriptor handling so that CUR_DSCR always
> points to the next descriptor to be processed.
>
> Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: Francisco Iglesias <frasse.iglesias@gmail.com>
> ---
> hw/dma/xlnx-zdma.c | 47 ++++++++++++++++++++++------------------------
> 1 file changed, 22 insertions(+), 25 deletions(-)
>
> diff --git a/hw/dma/xlnx-zdma.c b/hw/dma/xlnx-zdma.c
> index e856d233f2..1c45367f3c 100644
> --- a/hw/dma/xlnx-zdma.c
> +++ b/hw/dma/xlnx-zdma.c
> @@ -333,10 +333,28 @@ static void zdma_load_src_descriptor(XlnxZDMA *s)
> }
> }
>
> +static void zdma_update_descr_addr(XlnxZDMA *s, bool type,
> + unsigned int basereg)
> +{
> + uint64_t addr, next;
> +
> + if (type == DTYPE_LINEAR) {
> + addr = zdma_get_regaddr64(s, basereg);
> + next = addr + sizeof(s->dsc_dst);
> + } else {
> + addr = zdma_get_regaddr64(s, basereg);
> + addr += sizeof(s->dsc_dst);
> + address_space_read(s->dma_as, addr, s->attr, (void *) &next, 8);
> + }
> +
> + zdma_put_regaddr64(s, basereg, next);
> +}
> +
> static void zdma_load_dst_descriptor(XlnxZDMA *s)
> {
> uint64_t dst_addr;
> unsigned int ptype = ARRAY_FIELD_EX32(s->regs, ZDMA_CH_CTRL0, POINT_TYPE);
> + bool dst_type;
>
> if (ptype == PT_REG) {
> memcpy(&s->dsc_dst, &s->regs[R_ZDMA_CH_DST_DSCR_WORD0],
> @@ -349,24 +367,10 @@ static void zdma_load_dst_descriptor(XlnxZDMA *s)
> if (!zdma_load_descriptor(s, dst_addr, &s->dsc_dst)) {
> ARRAY_FIELD_DP32(s->regs, ZDMA_CH_ISR, AXI_RD_DST_DSCR, true);
> }
> -}
> -
> -static uint64_t zdma_update_descr_addr(XlnxZDMA *s, bool type,
> - unsigned int basereg)
> -{
> - uint64_t addr, next;
>
> - if (type == DTYPE_LINEAR) {
> - next = zdma_get_regaddr64(s, basereg);
> - next += sizeof(s->dsc_dst);
> - zdma_put_regaddr64(s, basereg, next);
> - } else {
> - addr = zdma_get_regaddr64(s, basereg);
> - addr += sizeof(s->dsc_dst);
> - address_space_read(s->dma_as, addr, s->attr, &next, 8);
> - zdma_put_regaddr64(s, basereg, next);
> - }
> - return next;
> + /* Advance the descriptor pointer. */
> + dst_type = FIELD_EX32(s->dsc_dst.words[3], ZDMA_CH_DST_DSCR_WORD3, TYPE);
> + zdma_update_descr_addr(s, dst_type, R_ZDMA_CH_DST_CUR_DSCR_LSB);
> }
>
> static void zdma_write_dst(XlnxZDMA *s, uint8_t *buf, uint32_t len)
> @@ -387,14 +391,7 @@ static void zdma_write_dst(XlnxZDMA *s, uint8_t *buf, uint32_t len)
> dst_size = FIELD_EX32(s->dsc_dst.words[2], ZDMA_CH_DST_DSCR_WORD2,
> SIZE);
> if (dst_size == 0 && ptype == PT_MEM) {
> - uint64_t next;
> - bool dst_type = FIELD_EX32(s->dsc_dst.words[3],
> - ZDMA_CH_DST_DSCR_WORD3,
> - TYPE);
> -
> - next = zdma_update_descr_addr(s, dst_type,
> - R_ZDMA_CH_DST_CUR_DSCR_LSB);
> - zdma_load_descriptor(s, next, &s->dsc_dst);
> + zdma_load_dst_descriptor(s);
> dst_size = FIELD_EX32(s->dsc_dst.words[2], ZDMA_CH_DST_DSCR_WORD2,
> SIZE);
> }
> --
> 2.20.1
>
On Thu, 2 Apr 2020 at 14:46, Edgar E. Iglesias <edgar.iglesias@gmail.com> wrote:
>
> From: "Edgar E. Iglesias" <edgar.iglesias@xilinx.com>
>
> Reorganize the descriptor handling so that CUR_DSCR always
> points to the next descriptor to be processed.
>
> Signed-off-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
> ---
This is just moved-code in this patch so I think it's
a separate issue, but it looks like you have an endianness
bug here:
> +static void zdma_update_descr_addr(XlnxZDMA *s, bool type,
> + unsigned int basereg)
> +{
> + uint64_t addr, next;
> +
> + if (type == DTYPE_LINEAR) {
> + addr = zdma_get_regaddr64(s, basereg);
> + next = addr + sizeof(s->dsc_dst);
> + } else {
> + addr = zdma_get_regaddr64(s, basereg);
> + addr += sizeof(s->dsc_dst);
> + address_space_read(s->dma_as, addr, s->attr, (void *) &next, 8);
This reads 8 bytes into the uint64_t 'next', which means
that the value from C's point of view will be different
for big-endian and little-endian hosts. You probably wanted
address_space_ldq_le(), assuming the h/w always does
little-endian reads and that these get_regaddr64 and
put_regaddr64 functions work with host-endian integers.
There's a similar problem elsewhere in the device where
it does this:
address_space_read(s->dma_as, addr, s->attr, buf, sizeof(XlnxZDMADescr));
and assumes the guest structure is the same layout and
endianness as the host struct XlnxDMADescr.
I'm not a huge fan of defining host C structs to match
guest data structures, but if you want to go that way
you ought to (a) be byteswapping the contents appropriately
and (b) have a compile-time assert that the size of the
struct is what you think it is and the compiler hasn't
inserted any helpful extra padding.
thanks
-- PMM
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