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[PATCH v3 4/8] dp8393x: Store CAM registers as 16-bit

Philippe Mathieu-Daudé posted 8 patches 4 years, 7 months ago
There is a newer version of this series
[PATCH v3 4/8] dp8393x: Store CAM registers as 16-bit
Posted by Philippe Mathieu-Daudé 4 years, 7 months ago 
Per the DP83932C datasheet from July 1995:

  4.0 SONIC Registers
  4.1 THE CAM UNIT

    The Content Addressable Memory (CAM) consists of sixteen
    48-bit entries for complete address filtering of network
    packets. Each entry corresponds to a 48-bit destination
    address that is user programmable and can contain any
    combination of Multicast or Physical addresses. Each entry
    is partitioned into three 16-bit CAM cells accessible
    through CAM Address Ports (CAP 2, CAP 1 and CAP 0) with
    CAP0 corresponding to the least significant 16 bits of
    the Destination Address and CAP2 corresponding to the
    most significant bits.

Store the CAM registers as 16-bit as it simplifies the code.
There is no change in the migration stream.

Co-developed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Co-developed-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
Missing:
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
---
 hw/net/dp8393x.c | 23 ++++++++++-------------
 1 file changed, 10 insertions(+), 13 deletions(-)

diff --git a/hw/net/dp8393x.c b/hw/net/dp8393x.c
index 64f3b0fc3ea..2c3047c8688 100644
--- a/hw/net/dp8393x.c
+++ b/hw/net/dp8393x.c
@@ -158,7 +158,7 @@ struct dp8393xState {
     MemoryRegion mmio;
 
     /* Registers */
-    uint8_t cam[16][6];
+    uint16_t cam[16][3];
     uint16_t regs[SONIC_REG_COUNT];
 
     /* Temporaries */
@@ -281,15 +281,13 @@ static void dp8393x_do_load_cam(dp8393xState *s)
         address_space_read(&s->as, dp8393x_cdp(s),
                            MEMTXATTRS_UNSPECIFIED, s->data, size);
         index = dp8393x_get(s, width, 0) & 0xf;
-        s->cam[index][0] = dp8393x_get(s, width, 1) & 0xff;
-        s->cam[index][1] = dp8393x_get(s, width, 1) >> 8;
-        s->cam[index][2] = dp8393x_get(s, width, 2) & 0xff;
-        s->cam[index][3] = dp8393x_get(s, width, 2) >> 8;
-        s->cam[index][4] = dp8393x_get(s, width, 3) & 0xff;
-        s->cam[index][5] = dp8393x_get(s, width, 3) >> 8;
-        trace_dp8393x_load_cam(index, s->cam[index][0], s->cam[index][1],
-                               s->cam[index][2], s->cam[index][3],
-                               s->cam[index][4], s->cam[index][5]);
+        s->cam[index][0] = dp8393x_get(s, width, 1);
+        s->cam[index][1] = dp8393x_get(s, width, 2);
+        s->cam[index][2] = dp8393x_get(s, width, 3);
+        trace_dp8393x_load_cam(index,
+                               s->cam[index][0] >> 8, s->cam[index][0] & 0xff,
+                               s->cam[index][1] >> 8, s->cam[index][1] & 0xff,
+                               s->cam[index][2] >> 8, s->cam[index][2] & 0xff);
         /* Move to next entry */
         s->regs[SONIC_CDC]--;
         s->regs[SONIC_CDP] += size;
@@ -592,8 +590,7 @@ static uint64_t dp8393x_read(void *opaque, hwaddr addr, unsigned int size)
     case SONIC_CAP1:
     case SONIC_CAP0:
         if (s->regs[SONIC_CR] & SONIC_CR_RST) {
-            val = s->cam[s->regs[SONIC_CEP] & 0xf][2 * (SONIC_CAP0 - reg) + 1] << 8;
-            val |= s->cam[s->regs[SONIC_CEP] & 0xf][2 * (SONIC_CAP0 - reg)];
+            val = s->cam[s->regs[SONIC_CEP] & 0xf][SONIC_CAP0 - reg];
         }
         break;
     /* All other registers have no special contraints */
@@ -989,7 +986,7 @@ static const VMStateDescription vmstate_dp8393x = {
     .version_id = 0,
     .minimum_version_id = 0,
     .fields = (VMStateField []) {
-        VMSTATE_BUFFER_UNSAFE(cam, dp8393xState, 0, 16 * 6),
+        VMSTATE_BUFFER_UNSAFE(cam, dp8393xState, 0, 16 * 3 * 2),
         VMSTATE_UINT16_ARRAY(regs, dp8393xState, SONIC_REG_COUNT),
         VMSTATE_END_OF_LIST()
     }
-- 
2.31.1
Re: [PATCH v3 4/8] dp8393x: Store CAM registers as 16-bit
Posted by Mark Cave-Ayland 4 years, 7 months ago 
On 10/07/2021 18:49, Philippe Mathieu-Daudé wrote:

> Per the DP83932C datasheet from July 1995:
> 
>    4.0 SONIC Registers
>    4.1 THE CAM UNIT
> 
>      The Content Addressable Memory (CAM) consists of sixteen
>      48-bit entries for complete address filtering of network
>      packets. Each entry corresponds to a 48-bit destination
>      address that is user programmable and can contain any
>      combination of Multicast or Physical addresses. Each entry
>      is partitioned into three 16-bit CAM cells accessible
>      through CAM Address Ports (CAP 2, CAP 1 and CAP 0) with
>      CAP0 corresponding to the least significant 16 bits of
>      the Destination Address and CAP2 corresponding to the
>      most significant bits.
> 
> Store the CAM registers as 16-bit as it simplifies the code.
> There is no change in the migration stream.
> 
> Co-developed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> Co-developed-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
> Missing:
> Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
> ---
>   hw/net/dp8393x.c | 23 ++++++++++-------------
>   1 file changed, 10 insertions(+), 13 deletions(-)
> 
> diff --git a/hw/net/dp8393x.c b/hw/net/dp8393x.c
> index 64f3b0fc3ea..2c3047c8688 100644
> --- a/hw/net/dp8393x.c
> +++ b/hw/net/dp8393x.c
> @@ -158,7 +158,7 @@ struct dp8393xState {
>       MemoryRegion mmio;
>   
>       /* Registers */
> -    uint8_t cam[16][6];
> +    uint16_t cam[16][3];
>       uint16_t regs[SONIC_REG_COUNT];
>   
>       /* Temporaries */
> @@ -281,15 +281,13 @@ static void dp8393x_do_load_cam(dp8393xState *s)
>           address_space_read(&s->as, dp8393x_cdp(s),
>                              MEMTXATTRS_UNSPECIFIED, s->data, size);
>           index = dp8393x_get(s, width, 0) & 0xf;
> -        s->cam[index][0] = dp8393x_get(s, width, 1) & 0xff;
> -        s->cam[index][1] = dp8393x_get(s, width, 1) >> 8;
> -        s->cam[index][2] = dp8393x_get(s, width, 2) & 0xff;
> -        s->cam[index][3] = dp8393x_get(s, width, 2) >> 8;
> -        s->cam[index][4] = dp8393x_get(s, width, 3) & 0xff;
> -        s->cam[index][5] = dp8393x_get(s, width, 3) >> 8;
> -        trace_dp8393x_load_cam(index, s->cam[index][0], s->cam[index][1],
> -                               s->cam[index][2], s->cam[index][3],
> -                               s->cam[index][4], s->cam[index][5]);
> +        s->cam[index][0] = dp8393x_get(s, width, 1);
> +        s->cam[index][1] = dp8393x_get(s, width, 2);
> +        s->cam[index][2] = dp8393x_get(s, width, 3);
> +        trace_dp8393x_load_cam(index,
> +                               s->cam[index][0] >> 8, s->cam[index][0] & 0xff,
> +                               s->cam[index][1] >> 8, s->cam[index][1] & 0xff,
> +                               s->cam[index][2] >> 8, s->cam[index][2] & 0xff);
>           /* Move to next entry */
>           s->regs[SONIC_CDC]--;
>           s->regs[SONIC_CDP] += size;
> @@ -592,8 +590,7 @@ static uint64_t dp8393x_read(void *opaque, hwaddr addr, unsigned int size)
>       case SONIC_CAP1:
>       case SONIC_CAP0:
>           if (s->regs[SONIC_CR] & SONIC_CR_RST) {
> -            val = s->cam[s->regs[SONIC_CEP] & 0xf][2 * (SONIC_CAP0 - reg) + 1] << 8;
> -            val |= s->cam[s->regs[SONIC_CEP] & 0xf][2 * (SONIC_CAP0 - reg)];
> +            val = s->cam[s->regs[SONIC_CEP] & 0xf][SONIC_CAP0 - reg];
>           }
>           break;
>       /* All other registers have no special contraints */
> @@ -989,7 +986,7 @@ static const VMStateDescription vmstate_dp8393x = {
>       .version_id = 0,
>       .minimum_version_id = 0,
>       .fields = (VMStateField []) {
> -        VMSTATE_BUFFER_UNSAFE(cam, dp8393xState, 0, 16 * 6),
> +        VMSTATE_BUFFER_UNSAFE(cam, dp8393xState, 0, 16 * 3 * 2),
>           VMSTATE_UINT16_ARRAY(regs, dp8393xState, SONIC_REG_COUNT),
>           VMSTATE_END_OF_LIST()
>       }

Reviewed-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>


ATB,

Mark.

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