[Qemu-devel] [PATCH v2 0/4] e1000: link auto-negotiation fixes

[Qemu-devel] [PATCH v2 0/4] e1000: link auto-negotiation fixes

[Gabriel L. Somlo]

New in v2:

  - checking for E1000_FLAG_AUTONEG in s->compat_flags when deciding
    whether to run the auto-negotiation timer vs. simply forcing the
    link up during e1000_set_link_status()

  - grouped E1000_FLAG_AUTONEG check in s->compat_flags tighter with
    the rest of the auto-negotiation checks in the two other locations
    they appear in the source code (hopefully improving clarity).

  - added patch to move the auto-negotiation timer function past set_ics()
    to avoid the need for a forward declaration.


This series contains a few fixes and improvements in the emulation
of link auto-negotiation:

  - use auto-negotiation when the link is bounced externally (e.g. via
    set_link <foo> down/up on the qemu monitor command line).

  - allow mii_tool on linux access to all the phy registers and flags
    it requires in order to report a successfully auto-negotiated link.

  - inject LSC interrupt upon successful link auto-negotiation (required
    by stock OS X e1000 driver).

Gabriel L. Somlo (4):
  e1000: emulate auto-negotiation during external link status change
  e1000: improve auto-negotiation reporting via mii-tool
  e1000: move e1000_autoneg_timer() to after set_ics()
  e1000: signal guest on successful link auto-negotiation

 hw/net/e1000.c      | 59 ++++++++++++++++++++++++++++++-----------------------
 hw/net/e1000_regs.h |  3 +++
 2 files changed, 36 insertions(+), 26 deletions(-)

-- 
1.9.3

[Qemu-devel] [PATCH v2 1/4] e1000: emulate auto-negotiation during external link status change

[Gabriel L. Somlo]

This patch emulates auto-negotiation when the network link status
is modified externally (i.e. via "set_link <id> off/on").

Also, a couple of cleanup items:
  - unset PHY status reg. AUTONEG_COMPLETE during link_down()
  - set PHY status reg. AUTONEG_COMPLETE during autoneg_timer() only
    if we actually brought the link up.
  - group all checks for "can we, and should we autonegotiate?"
    together for more clarity.

Signed-off-by: Gabriel Somlo <somlo@cmu.edu>
Reviewed-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 hw/net/e1000.c | 35 +++++++++++++++++++----------------
 1 file changed, 19 insertions(+), 16 deletions(-)

diff --git a/hw/net/e1000.c b/hw/net/e1000.c
index 57bdffd..9c6af06 100644
--- a/hw/net/e1000.c
+++ b/hw/net/e1000.c
@@ -175,6 +175,7 @@ e1000_link_down(E1000State *s)
 {
     s->mac_reg[STATUS] &= ~E1000_STATUS_LU;
     s->phy_reg[PHY_STATUS] &= ~MII_SR_LINK_STATUS;
+    s->phy_reg[PHY_STATUS] &= ~MII_SR_AUTONEG_COMPLETE;
 }
 
 static void
@@ -197,7 +198,6 @@ set_phy_ctrl(E1000State *s, int index, uint16_t val)
     }
     if ((val & MII_CR_AUTO_NEG_EN) && (val & MII_CR_RESTART_AUTO_NEG)) {
         e1000_link_down(s);
-        s->phy_reg[PHY_STATUS] &= ~MII_SR_AUTONEG_COMPLETE;
         DBGOUT(PHY, "Start link auto negotiation\n");
         timer_mod(s->autoneg_timer, qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) + 500);
     }
@@ -209,9 +209,9 @@ e1000_autoneg_timer(void *opaque)
     E1000State *s = opaque;
     if (!qemu_get_queue(s->nic)->link_down) {
         e1000_link_up(s);
+        s->phy_reg[PHY_STATUS] |= MII_SR_AUTONEG_COMPLETE;
+        DBGOUT(PHY, "Auto negotiation is completed\n");
     }
-    s->phy_reg[PHY_STATUS] |= MII_SR_AUTONEG_COMPLETE;
-    DBGOUT(PHY, "Auto negotiation is completed\n");
 }
 
 static void (*phyreg_writeops[])(E1000State *, int, uint16_t) = {
@@ -853,7 +853,16 @@ e1000_set_link_status(NetClientState *nc)
     if (nc->link_down) {
         e1000_link_down(s);
     } else {
-        e1000_link_up(s);
+        if (s->compat_flags & E1000_FLAG_AUTONEG &&
+            s->phy_reg[PHY_CTRL] & MII_CR_AUTO_NEG_EN &&
+            s->phy_reg[PHY_CTRL] & MII_CR_RESTART_AUTO_NEG &&
+            !(s->phy_reg[PHY_STATUS] & MII_SR_AUTONEG_COMPLETE)) {
+            /* emulate auto-negotiation if supported */
+            timer_mod(s->autoneg_timer,
+                      qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) + 500);
+        } else {
+            e1000_link_up(s);
+        }
     }
 
     if (s->mac_reg[STATUS] != old_status)
@@ -1279,16 +1288,13 @@ static void e1000_pre_save(void *opaque)
         e1000_mit_timer(s);
     }
 
-    if (!(s->compat_flags & E1000_FLAG_AUTONEG)) {
-        return;
-    }
-
     /*
-     * If link is down and auto-negotiation is ongoing, complete
-     * auto-negotiation immediately.  This allows is to look at
-     * MII_SR_AUTONEG_COMPLETE to infer link status on load.
+     * If link is down and auto-negotiation is supported and ongoing,
+     * complete auto-negotiation immediately. This allows us to look
+     * at MII_SR_AUTONEG_COMPLETE to infer link status on load.
      */
     if (nc->link_down &&
+        s->compat_flags & E1000_FLAG_AUTONEG &&
         s->phy_reg[PHY_CTRL] & MII_CR_AUTO_NEG_EN &&
         s->phy_reg[PHY_CTRL] & MII_CR_RESTART_AUTO_NEG) {
          s->phy_reg[PHY_STATUS] |= MII_SR_AUTONEG_COMPLETE;
@@ -1313,11 +1319,8 @@ static int e1000_post_load(void *opaque, int version_id)
      * Alternatively, restart link negotiation if it was in progress. */
     nc->link_down = (s->mac_reg[STATUS] & E1000_STATUS_LU) == 0;
 
-    if (!(s->compat_flags & E1000_FLAG_AUTONEG)) {
-        return 0;
-    }
-
-    if (s->phy_reg[PHY_CTRL] & MII_CR_AUTO_NEG_EN &&
+    if (s->compat_flags & E1000_FLAG_AUTONEG &&
+        s->phy_reg[PHY_CTRL] & MII_CR_AUTO_NEG_EN &&
         s->phy_reg[PHY_CTRL] & MII_CR_RESTART_AUTO_NEG &&
         !(s->phy_reg[PHY_STATUS] & MII_SR_AUTONEG_COMPLETE)) {
         nc->link_down = false;
-- 
1.9.3

Re: [Qemu-devel] [PATCH v2 1/4] e1000: emulate auto-negotiation during external link status change

[Michael S. Tsirkin]

On Thu, Jun 19, 2014 at 11:55:33AM -0400, Gabriel L. Somlo wrote:
> This patch emulates auto-negotiation when the network link status
> is modified externally (i.e. via "set_link <id> off/on").
> 
> Also, a couple of cleanup items:
>   - unset PHY status reg. AUTONEG_COMPLETE during link_down()
>   - set PHY status reg. AUTONEG_COMPLETE during autoneg_timer() only
>     if we actually brought the link up.
>   - group all checks for "can we, and should we autonegotiate?"
>     together for more clarity.
> 
> Signed-off-by: Gabriel Somlo <somlo@cmu.edu>
> Reviewed-by: Alexander Graf <agraf@suse.de>
> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>

Now you did this cleanup, let's have a function
to check autonegotiation in a single place.

Can be patch on top.

> ---
>  hw/net/e1000.c | 35 +++++++++++++++++++----------------
>  1 file changed, 19 insertions(+), 16 deletions(-)
> 
> diff --git a/hw/net/e1000.c b/hw/net/e1000.c
> index 57bdffd..9c6af06 100644
> --- a/hw/net/e1000.c
> +++ b/hw/net/e1000.c
> @@ -175,6 +175,7 @@ e1000_link_down(E1000State *s)
>  {
>      s->mac_reg[STATUS] &= ~E1000_STATUS_LU;
>      s->phy_reg[PHY_STATUS] &= ~MII_SR_LINK_STATUS;
> +    s->phy_reg[PHY_STATUS] &= ~MII_SR_AUTONEG_COMPLETE;
>  }
>  
>  static void
> @@ -197,7 +198,6 @@ set_phy_ctrl(E1000State *s, int index, uint16_t val)
>      }
>      if ((val & MII_CR_AUTO_NEG_EN) && (val & MII_CR_RESTART_AUTO_NEG)) {
>          e1000_link_down(s);
> -        s->phy_reg[PHY_STATUS] &= ~MII_SR_AUTONEG_COMPLETE;
>          DBGOUT(PHY, "Start link auto negotiation\n");
>          timer_mod(s->autoneg_timer, qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) + 500);
>      }
> @@ -209,9 +209,9 @@ e1000_autoneg_timer(void *opaque)
>      E1000State *s = opaque;
>      if (!qemu_get_queue(s->nic)->link_down) {
>          e1000_link_up(s);
> +        s->phy_reg[PHY_STATUS] |= MII_SR_AUTONEG_COMPLETE;
> +        DBGOUT(PHY, "Auto negotiation is completed\n");
>      }
> -    s->phy_reg[PHY_STATUS] |= MII_SR_AUTONEG_COMPLETE;
> -    DBGOUT(PHY, "Auto negotiation is completed\n");
>  }
>  
>  static void (*phyreg_writeops[])(E1000State *, int, uint16_t) = {
> @@ -853,7 +853,16 @@ e1000_set_link_status(NetClientState *nc)
>      if (nc->link_down) {
>          e1000_link_down(s);
>      } else {
> -        e1000_link_up(s);
> +        if (s->compat_flags & E1000_FLAG_AUTONEG &&
> +            s->phy_reg[PHY_CTRL] & MII_CR_AUTO_NEG_EN &&
> +            s->phy_reg[PHY_CTRL] & MII_CR_RESTART_AUTO_NEG &&
> +            !(s->phy_reg[PHY_STATUS] & MII_SR_AUTONEG_COMPLETE)) {
> +            /* emulate auto-negotiation if supported */
> +            timer_mod(s->autoneg_timer,
> +                      qemu_clock_get_ms(QEMU_CLOCK_VIRTUAL) + 500);
> +        } else {
> +            e1000_link_up(s);
> +        }
>      }
>  
>      if (s->mac_reg[STATUS] != old_status)
> @@ -1279,16 +1288,13 @@ static void e1000_pre_save(void *opaque)
>          e1000_mit_timer(s);
>      }
>  
> -    if (!(s->compat_flags & E1000_FLAG_AUTONEG)) {
> -        return;
> -    }
> -
>      /*
> -     * If link is down and auto-negotiation is ongoing, complete
> -     * auto-negotiation immediately.  This allows is to look at
> -     * MII_SR_AUTONEG_COMPLETE to infer link status on load.
> +     * If link is down and auto-negotiation is supported and ongoing,
> +     * complete auto-negotiation immediately. This allows us to look
> +     * at MII_SR_AUTONEG_COMPLETE to infer link status on load.
>       */
>      if (nc->link_down &&
> +        s->compat_flags & E1000_FLAG_AUTONEG &&
>          s->phy_reg[PHY_CTRL] & MII_CR_AUTO_NEG_EN &&
>          s->phy_reg[PHY_CTRL] & MII_CR_RESTART_AUTO_NEG) {
>           s->phy_reg[PHY_STATUS] |= MII_SR_AUTONEG_COMPLETE;
> @@ -1313,11 +1319,8 @@ static int e1000_post_load(void *opaque, int version_id)
>       * Alternatively, restart link negotiation if it was in progress. */
>      nc->link_down = (s->mac_reg[STATUS] & E1000_STATUS_LU) == 0;
>  
> -    if (!(s->compat_flags & E1000_FLAG_AUTONEG)) {
> -        return 0;
> -    }
> -
> -    if (s->phy_reg[PHY_CTRL] & MII_CR_AUTO_NEG_EN &&
> +    if (s->compat_flags & E1000_FLAG_AUTONEG &&
> +        s->phy_reg[PHY_CTRL] & MII_CR_AUTO_NEG_EN &&
>          s->phy_reg[PHY_CTRL] & MII_CR_RESTART_AUTO_NEG &&
>          !(s->phy_reg[PHY_STATUS] & MII_SR_AUTONEG_COMPLETE)) {
>          nc->link_down = false;
> -- 
> 1.9.3

[Qemu-devel] [PATCH v2 2/4] e1000: improve auto-negotiation reporting via mii-tool

[Gabriel L. Somlo]

Using mii-tool (on F20-live), the following output is produced:

  SIOCGMIIREG on ens3 failed: Input/output error
  ens3: no autonegotiation, 1000baseT-FD flow-control, link ok

The first line (SIOCGMIIREG error) is due to mii-tool's inability
to read the PHY auto-negotiation expansion register.
On the second line, "no autonegotiation" is wrong, and caused by
the absence of a flag in the link partner ability register which
would indicate that our link partner has acked us. This flag is
listed as "reserved" in the Intel e1000 manual, but mii-tool uses
it as LPA_LPACK from /usr/include/linux/mii.h.

This patch adds read access to PHY_AUTONEG_EXP and defines the
link partner ack flag, allowing mii-tool to generate output as
normally expected:

  ens3: negotiated 1000baseT-FD flow-control, link ok

Signed-off-by: Gabriel Somlo <somlo@cmu.edu>
Reviewed-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 hw/net/e1000.c      | 5 ++++-
 hw/net/e1000_regs.h | 3 +++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/hw/net/e1000.c b/hw/net/e1000.c
index 9c6af06..d6ef802 100644
--- a/hw/net/e1000.c
+++ b/hw/net/e1000.c
@@ -176,6 +176,7 @@ e1000_link_down(E1000State *s)
     s->mac_reg[STATUS] &= ~E1000_STATUS_LU;
     s->phy_reg[PHY_STATUS] &= ~MII_SR_LINK_STATUS;
     s->phy_reg[PHY_STATUS] &= ~MII_SR_AUTONEG_COMPLETE;
+    s->phy_reg[PHY_LP_ABILITY] &= ~MII_LPAR_LPACK;
 }
 
 static void
@@ -209,6 +210,7 @@ e1000_autoneg_timer(void *opaque)
     E1000State *s = opaque;
     if (!qemu_get_queue(s->nic)->link_down) {
         e1000_link_up(s);
+        s->phy_reg[PHY_LP_ABILITY] |= MII_LPAR_LPACK;
         s->phy_reg[PHY_STATUS] |= MII_SR_AUTONEG_COMPLETE;
         DBGOUT(PHY, "Auto negotiation is completed\n");
     }
@@ -227,7 +229,8 @@ static const char phy_regcap[0x20] = {
     [PHY_CTRL] = PHY_RW,	[PHY_1000T_CTRL] = PHY_RW,
     [PHY_LP_ABILITY] = PHY_R,	[PHY_1000T_STATUS] = PHY_R,
     [PHY_AUTONEG_ADV] = PHY_RW,	[M88E1000_RX_ERR_CNTR] = PHY_R,
-    [PHY_ID2] = PHY_R,		[M88E1000_PHY_SPEC_STATUS] = PHY_R
+    [PHY_ID2] = PHY_R,		[M88E1000_PHY_SPEC_STATUS] = PHY_R,
+    [PHY_AUTONEG_EXP] = PHY_R,
 };
 
 /* PHY_ID2 documented in 8254x_GBe_SDM.pdf, pp. 250 */
diff --git a/hw/net/e1000_regs.h b/hw/net/e1000_regs.h
index 13ac671..60b96aa 100644
--- a/hw/net/e1000_regs.h
+++ b/hw/net/e1000_regs.h
@@ -384,6 +384,9 @@
 #define MII_SR_100X_FD_CAPS      0x4000	/* 100X  Full Duplex Capable */
 #define MII_SR_100T4_CAPS        0x8000	/* 100T4 Capable */
 
+/* PHY Link Partner Ability Register */
+#define MII_LPAR_LPACK           0x4000 /* Acked by link partner */
+
 /* Interrupt Cause Read */
 #define E1000_ICR_TXDW          0x00000001 /* Transmit desc written back */
 #define E1000_ICR_TXQE          0x00000002 /* Transmit Queue empty */
-- 
1.9.3

[Qemu-devel] [PATCH v2 3/4] e1000: move e1000_autoneg_timer() to after set_ics()

[Gabriel L. Somlo]

Enable calling set_ics() from within e1000_autoneg_timer() without
the need for a forward declaration.

This patch contains no functional changes.

Signed-off-by: Gabriel Somlo <somlo@cmu.edu>
---
 hw/net/e1000.c | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/hw/net/e1000.c b/hw/net/e1000.c
index d6ef802..fd9b9be 100644
--- a/hw/net/e1000.c
+++ b/hw/net/e1000.c
@@ -204,18 +204,6 @@ set_phy_ctrl(E1000State *s, int index, uint16_t val)
     }
 }
 
-static void
-e1000_autoneg_timer(void *opaque)
-{
-    E1000State *s = opaque;
-    if (!qemu_get_queue(s->nic)->link_down) {
-        e1000_link_up(s);
-        s->phy_reg[PHY_LP_ABILITY] |= MII_LPAR_LPACK;
-        s->phy_reg[PHY_STATUS] |= MII_SR_AUTONEG_COMPLETE;
-        DBGOUT(PHY, "Auto negotiation is completed\n");
-    }
-}
-
 static void (*phyreg_writeops[])(E1000State *, int, uint16_t) = {
     [PHY_CTRL] = set_phy_ctrl,
 };
@@ -347,6 +335,18 @@ set_ics(E1000State *s, int index, uint32_t val)
     set_interrupt_cause(s, 0, val | s->mac_reg[ICR]);
 }
 
+static void
+e1000_autoneg_timer(void *opaque)
+{
+    E1000State *s = opaque;
+    if (!qemu_get_queue(s->nic)->link_down) {
+        e1000_link_up(s);
+        s->phy_reg[PHY_LP_ABILITY] |= MII_LPAR_LPACK;
+        s->phy_reg[PHY_STATUS] |= MII_SR_AUTONEG_COMPLETE;
+        DBGOUT(PHY, "Auto negotiation is completed\n");
+    }
+}
+
 static int
 rxbufsize(uint32_t v)
 {
-- 
1.9.3

[Qemu-devel] [PATCH v2 4/4] e1000: signal guest on successful link auto-negotiation

[Gabriel L. Somlo]

Generate a link status change interrupt once link auto-netotiation
is successfully completed. This does not affect Linux and Windows
(XP and 7 tested) in any way, but is needed by the stock OS X driver
(AppleIntel8254XEthernet.kext), which would otherwise fail to notice
the link status change event.

Signed-off-by: Gabriel Somlo <somlo@cmu.edu>
Reviewed-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 hw/net/e1000.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/hw/net/e1000.c b/hw/net/e1000.c
index fd9b9be..8ee5225 100644
--- a/hw/net/e1000.c
+++ b/hw/net/e1000.c
@@ -344,6 +344,7 @@ e1000_autoneg_timer(void *opaque)
         s->phy_reg[PHY_LP_ABILITY] |= MII_LPAR_LPACK;
         s->phy_reg[PHY_STATUS] |= MII_SR_AUTONEG_COMPLETE;
         DBGOUT(PHY, "Auto negotiation is completed\n");
+        set_ics(s, 0, E1000_ICS_LSC); /* signal link status change to guest */
     }
 }
 
-- 
1.9.3

Re: [Qemu-devel] [PATCH v2 0/4] e1000: link auto-negotiation fixes

[Michael S. Tsirkin]

On Thu, Jun 19, 2014 at 11:55:32AM -0400, Gabriel L. Somlo wrote:
> New in v2:
> 
>   - checking for E1000_FLAG_AUTONEG in s->compat_flags when deciding
>     whether to run the auto-negotiation timer vs. simply forcing the
>     link up during e1000_set_link_status()
> 
>   - grouped E1000_FLAG_AUTONEG check in s->compat_flags tighter with
>     the rest of the auto-negotiation checks in the two other locations
>     they appear in the source code (hopefully improving clarity).
> 
>   - added patch to move the auto-negotiation timer function past set_ics()
>     to avoid the need for a forward declaration.
> 


Applied, thanks everyone.

> This series contains a few fixes and improvements in the emulation
> of link auto-negotiation:
> 
>   - use auto-negotiation when the link is bounced externally (e.g. via
>     set_link <foo> down/up on the qemu monitor command line).
> 
>   - allow mii_tool on linux access to all the phy registers and flags
>     it requires in order to report a successfully auto-negotiated link.
> 
>   - inject LSC interrupt upon successful link auto-negotiation (required
>     by stock OS X e1000 driver).
> 
> Gabriel L. Somlo (4):
>   e1000: emulate auto-negotiation during external link status change
>   e1000: improve auto-negotiation reporting via mii-tool
>   e1000: move e1000_autoneg_timer() to after set_ics()
>   e1000: signal guest on successful link auto-negotiation
> 
>  hw/net/e1000.c      | 59 ++++++++++++++++++++++++++++++-----------------------
>  hw/net/e1000_regs.h |  3 +++
>  2 files changed, 36 insertions(+), 26 deletions(-)
> 
> -- 
> 1.9.3