From: Tom Lendacky <thomas.lendacky@amd.com>
To: <netdev@vger.kernel.org>
Cc: Florian Fainelli <f.fainelli@gmail.com>,
David Miller <davem@davemloft.net>
Subject: [PATCH net-next v1 06/21] amd-xgbe: Add support for clause 37 auto-negotiation
Date: Thu, 3 Nov 2016 08:28:44 -0500 [thread overview]
Message-ID: <20161103132844.3437.70861.stgit@tlendack-t1.amdoffice.net> (raw)
In-Reply-To: <20161103132744.3437.27332.stgit@tlendack-t1.amdoffice.net>
Add support to be able to use clause 37 auto-negotiation.
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
---
drivers/net/ethernet/amd/xgbe/xgbe-common.h | 41 +++++
drivers/net/ethernet/amd/xgbe/xgbe-mdio.c | 242 ++++++++++++++++++++++++++-
drivers/net/ethernet/amd/xgbe/xgbe.h | 11 +
3 files changed, 286 insertions(+), 8 deletions(-)
diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-common.h b/drivers/net/ethernet/amd/xgbe/xgbe-common.h
index 695e982..8bcf4ef 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-common.h
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-common.h
@@ -1027,6 +1027,10 @@
#define MDIO_PMA_10GBR_FECCTRL 0x00ab
#endif
+#ifndef MDIO_PCS_DIG_CTRL
+#define MDIO_PCS_DIG_CTRL 0x8000
+#endif
+
#ifndef MDIO_AN_XNP
#define MDIO_AN_XNP 0x0016
#endif
@@ -1047,10 +1051,34 @@
#define MDIO_AN_INT 0x8002
#endif
+#ifndef MDIO_VEND2_AN_ADVERTISE
+#define MDIO_VEND2_AN_ADVERTISE 0x0004
+#endif
+
+#ifndef MDIO_VEND2_AN_LP_ABILITY
+#define MDIO_VEND2_AN_LP_ABILITY 0x0005
+#endif
+
+#ifndef MDIO_VEND2_AN_CTRL
+#define MDIO_VEND2_AN_CTRL 0x8001
+#endif
+
+#ifndef MDIO_VEND2_AN_STAT
+#define MDIO_VEND2_AN_STAT 0x8002
+#endif
+
#ifndef MDIO_CTRL1_SPEED1G
#define MDIO_CTRL1_SPEED1G (MDIO_CTRL1_SPEED10G & ~BMCR_SPEED100)
#endif
+#ifndef MDIO_VEND2_CTRL1_AN_ENABLE
+#define MDIO_VEND2_CTRL1_AN_ENABLE BIT(12)
+#endif
+
+#ifndef MDIO_VEND2_CTRL1_AN_RESTART
+#define MDIO_VEND2_CTRL1_AN_RESTART BIT(9)
+#endif
+
/* MDIO mask values */
#define XGBE_AN_CL73_INT_CMPLT BIT(0)
#define XGBE_AN_CL73_INC_LINK BIT(1)
@@ -1065,6 +1093,19 @@
#define XGBE_KR_TRAINING_START BIT(0)
#define XGBE_KR_TRAINING_ENABLE BIT(1)
+#define XGBE_PCS_CL37_BP BIT(12)
+
+#define XGBE_AN_CL37_INT_CMPLT BIT(0)
+#define XGBE_AN_CL37_INT_MASK 0x01
+
+#define XGBE_AN_CL37_HD_MASK 0x40
+#define XGBE_AN_CL37_FD_MASK 0x20
+
+#define XGBE_AN_CL37_PCS_MODE_MASK 0x06
+#define XGBE_AN_CL37_PCS_MODE_BASEX 0x00
+#define XGBE_AN_CL37_PCS_MODE_SGMII 0x04
+#define XGBE_AN_CL37_TX_CONFIG_MASK 0x08
+
/* Bit setting and getting macros
* The get macro will extract the current bit field value from within
* the variable
diff --git a/drivers/net/ethernet/amd/xgbe/xgbe-mdio.c b/drivers/net/ethernet/amd/xgbe/xgbe-mdio.c
index d5bfbe4..723eb90 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe-mdio.c
+++ b/drivers/net/ethernet/amd/xgbe/xgbe-mdio.c
@@ -125,6 +125,41 @@
#include "xgbe.h"
#include "xgbe-common.h"
+static void xgbe_an37_clear_interrupts(struct xgbe_prv_data *pdata)
+{
+ int reg;
+
+ reg = XMDIO_READ(pdata, MDIO_MMD_VEND2, MDIO_VEND2_AN_STAT);
+ reg &= ~XGBE_AN_CL37_INT_MASK;
+ XMDIO_WRITE(pdata, MDIO_MMD_VEND2, MDIO_VEND2_AN_STAT, reg);
+}
+
+static void xgbe_an37_disable_interrupts(struct xgbe_prv_data *pdata)
+{
+ int reg;
+
+ reg = XMDIO_READ(pdata, MDIO_MMD_VEND2, MDIO_VEND2_AN_CTRL);
+ reg &= ~XGBE_AN_CL37_INT_MASK;
+ XMDIO_WRITE(pdata, MDIO_MMD_VEND2, MDIO_VEND2_AN_CTRL, reg);
+
+ reg = XMDIO_READ(pdata, MDIO_MMD_PCS, MDIO_PCS_DIG_CTRL);
+ reg &= ~XGBE_PCS_CL37_BP;
+ XMDIO_WRITE(pdata, MDIO_MMD_PCS, MDIO_PCS_DIG_CTRL, reg);
+}
+
+static void xgbe_an37_enable_interrupts(struct xgbe_prv_data *pdata)
+{
+ int reg;
+
+ reg = XMDIO_READ(pdata, MDIO_MMD_PCS, MDIO_PCS_DIG_CTRL);
+ reg |= XGBE_PCS_CL37_BP;
+ XMDIO_WRITE(pdata, MDIO_MMD_PCS, MDIO_PCS_DIG_CTRL, reg);
+
+ reg = XMDIO_READ(pdata, MDIO_MMD_VEND2, MDIO_VEND2_AN_CTRL);
+ reg |= XGBE_AN_CL37_INT_MASK;
+ XMDIO_WRITE(pdata, MDIO_MMD_VEND2, MDIO_VEND2_AN_CTRL, reg);
+}
+
static void xgbe_an73_clear_interrupts(struct xgbe_prv_data *pdata)
{
XMDIO_WRITE(pdata, MDIO_MMD_AN, MDIO_AN_INT, 0);
@@ -146,11 +181,21 @@ static void xgbe_an_enable_interrupts(struct xgbe_prv_data *pdata)
case XGBE_AN_MODE_CL73:
xgbe_an73_enable_interrupts(pdata);
break;
+ case XGBE_AN_MODE_CL37:
+ case XGBE_AN_MODE_CL37_SGMII:
+ xgbe_an37_enable_interrupts(pdata);
+ break;
default:
break;
}
}
+static void xgbe_an_clear_interrupts_all(struct xgbe_prv_data *pdata)
+{
+ xgbe_an73_clear_interrupts(pdata);
+ xgbe_an37_clear_interrupts(pdata);
+}
+
static void xgbe_an73_enable_kr_training(struct xgbe_prv_data *pdata)
{
unsigned int reg;
@@ -258,6 +303,39 @@ static bool xgbe_use_mode(struct xgbe_prv_data *pdata,
return pdata->phy_if.phy_impl.use_mode(pdata, mode);
}
+static void xgbe_an37_set(struct xgbe_prv_data *pdata, bool enable,
+ bool restart)
+{
+ unsigned int reg;
+
+ reg = XMDIO_READ(pdata, MDIO_MMD_VEND2, MDIO_CTRL1);
+ reg &= ~MDIO_VEND2_CTRL1_AN_ENABLE;
+
+ if (enable)
+ reg |= MDIO_VEND2_CTRL1_AN_ENABLE;
+
+ if (restart)
+ reg |= MDIO_VEND2_CTRL1_AN_RESTART;
+
+ XMDIO_WRITE(pdata, MDIO_MMD_VEND2, MDIO_CTRL1, reg);
+}
+
+static void xgbe_an37_restart(struct xgbe_prv_data *pdata)
+{
+ xgbe_an37_enable_interrupts(pdata);
+ xgbe_an37_set(pdata, true, true);
+
+ netif_dbg(pdata, link, pdata->netdev, "CL37 AN enabled/restarted\n");
+}
+
+static void xgbe_an37_disable(struct xgbe_prv_data *pdata)
+{
+ xgbe_an37_set(pdata, false, false);
+ xgbe_an37_disable_interrupts(pdata);
+
+ netif_dbg(pdata, link, pdata->netdev, "CL37 AN disabled\n");
+}
+
static void xgbe_an73_set(struct xgbe_prv_data *pdata, bool enable,
bool restart)
{
@@ -297,6 +375,10 @@ static void xgbe_an_restart(struct xgbe_prv_data *pdata)
case XGBE_AN_MODE_CL73:
xgbe_an73_restart(pdata);
break;
+ case XGBE_AN_MODE_CL37:
+ case XGBE_AN_MODE_CL37_SGMII:
+ xgbe_an37_restart(pdata);
+ break;
default:
break;
}
@@ -308,11 +390,21 @@ static void xgbe_an_disable(struct xgbe_prv_data *pdata)
case XGBE_AN_MODE_CL73:
xgbe_an73_disable(pdata);
break;
+ case XGBE_AN_MODE_CL37:
+ case XGBE_AN_MODE_CL37_SGMII:
+ xgbe_an37_disable(pdata);
+ break;
default:
break;
}
}
+static void xgbe_an_disable_all(struct xgbe_prv_data *pdata)
+{
+ xgbe_an73_disable(pdata);
+ xgbe_an37_disable(pdata);
+}
+
static enum xgbe_an xgbe_an73_tx_training(struct xgbe_prv_data *pdata,
enum xgbe_rx *state)
{
@@ -484,6 +576,30 @@ static enum xgbe_an xgbe_an73_incompat_link(struct xgbe_prv_data *pdata)
return XGBE_AN_INCOMPAT_LINK;
}
+static void xgbe_an37_isr(struct xgbe_prv_data *pdata)
+{
+ unsigned int reg;
+
+ /* Disable AN interrupts */
+ xgbe_an37_disable_interrupts(pdata);
+
+ /* Save the interrupt(s) that fired */
+ reg = XMDIO_READ(pdata, MDIO_MMD_VEND2, MDIO_VEND2_AN_STAT);
+ pdata->an_int = reg & XGBE_AN_CL37_INT_MASK;
+ pdata->an_status = reg & ~XGBE_AN_CL37_INT_MASK;
+
+ if (pdata->an_int) {
+ /* Clear the interrupt(s) that fired and process them */
+ reg &= ~XGBE_AN_CL37_INT_MASK;
+ XMDIO_WRITE(pdata, MDIO_MMD_VEND2, MDIO_VEND2_AN_STAT, reg);
+
+ queue_work(pdata->an_workqueue, &pdata->an_irq_work);
+ } else {
+ /* Enable AN interrupts */
+ xgbe_an37_enable_interrupts(pdata);
+ }
+}
+
static void xgbe_an73_isr(struct xgbe_prv_data *pdata)
{
/* Disable AN interrupts */
@@ -513,6 +629,10 @@ static irqreturn_t xgbe_an_isr(int irq, void *data)
case XGBE_AN_MODE_CL73:
xgbe_an73_isr(pdata);
break;
+ case XGBE_AN_MODE_CL37:
+ case XGBE_AN_MODE_CL37_SGMII:
+ xgbe_an37_isr(pdata);
+ break;
default:
break;
}
@@ -553,6 +673,64 @@ static const char *xgbe_state_as_string(enum xgbe_an state)
}
}
+static void xgbe_an37_state_machine(struct xgbe_prv_data *pdata)
+{
+ enum xgbe_an cur_state = pdata->an_state;
+
+ if (!pdata->an_int)
+ return;
+
+ if (pdata->an_int & XGBE_AN_CL37_INT_CMPLT) {
+ pdata->an_state = XGBE_AN_COMPLETE;
+ pdata->an_int &= ~XGBE_AN_CL37_INT_CMPLT;
+
+ /* If SGMII is enabled, check the link status */
+ if ((pdata->an_mode == XGBE_AN_MODE_CL37_SGMII) &&
+ !(pdata->an_status & XGBE_SGMII_AN_LINK_STATUS))
+ pdata->an_state = XGBE_AN_NO_LINK;
+ }
+
+ netif_dbg(pdata, link, pdata->netdev, "CL37 AN %s\n",
+ xgbe_state_as_string(pdata->an_state));
+
+ cur_state = pdata->an_state;
+
+ switch (pdata->an_state) {
+ case XGBE_AN_READY:
+ break;
+
+ case XGBE_AN_COMPLETE:
+ netif_dbg(pdata, link, pdata->netdev,
+ "Auto negotiation successful\n");
+ break;
+
+ case XGBE_AN_NO_LINK:
+ break;
+
+ default:
+ pdata->an_state = XGBE_AN_ERROR;
+ }
+
+ if (pdata->an_state == XGBE_AN_ERROR) {
+ netdev_err(pdata->netdev,
+ "error during auto-negotiation, state=%u\n",
+ cur_state);
+
+ pdata->an_int = 0;
+ xgbe_an37_clear_interrupts(pdata);
+ }
+
+ if (pdata->an_state >= XGBE_AN_COMPLETE) {
+ pdata->an_result = pdata->an_state;
+ pdata->an_state = XGBE_AN_READY;
+
+ netif_dbg(pdata, link, pdata->netdev, "CL37 AN result: %s\n",
+ xgbe_state_as_string(pdata->an_result));
+ }
+
+ xgbe_an37_enable_interrupts(pdata);
+}
+
static void xgbe_an73_state_machine(struct xgbe_prv_data *pdata)
{
enum xgbe_an cur_state = pdata->an_state;
@@ -574,8 +752,6 @@ static void xgbe_an73_state_machine(struct xgbe_prv_data *pdata)
pdata->an_state = XGBE_AN_ERROR;
}
- pdata->an_result = pdata->an_state;
-
again:
netif_dbg(pdata, link, pdata->netdev, "CL73 AN %s\n",
xgbe_state_as_string(pdata->an_state));
@@ -656,6 +832,10 @@ static void xgbe_an_state_machine(struct work_struct *work)
case XGBE_AN_MODE_CL73:
xgbe_an73_state_machine(pdata);
break;
+ case XGBE_AN_MODE_CL37:
+ case XGBE_AN_MODE_CL37_SGMII:
+ xgbe_an37_state_machine(pdata);
+ break;
default:
break;
}
@@ -663,6 +843,50 @@ static void xgbe_an_state_machine(struct work_struct *work)
mutex_unlock(&pdata->an_mutex);
}
+static void xgbe_an37_init(struct xgbe_prv_data *pdata)
+{
+ unsigned int reg;
+
+ /* Set up Advertisement register */
+ reg = XMDIO_READ(pdata, MDIO_MMD_VEND2, MDIO_VEND2_AN_ADVERTISE);
+ if (pdata->phy.advertising & ADVERTISED_Pause)
+ reg |= 0x100;
+ else
+ reg &= ~0x100;
+
+ if (pdata->phy.advertising & ADVERTISED_Asym_Pause)
+ reg |= 0x80;
+ else
+ reg &= ~0x80;
+
+ /* Full duplex, but not half */
+ reg |= XGBE_AN_CL37_FD_MASK;
+ reg &= ~XGBE_AN_CL37_HD_MASK;
+
+ XMDIO_WRITE(pdata, MDIO_MMD_VEND2, MDIO_VEND2_AN_ADVERTISE, reg);
+
+ /* Set up the Control register */
+ reg = XMDIO_READ(pdata, MDIO_MMD_VEND2, MDIO_VEND2_AN_CTRL);
+ reg &= XGBE_AN_CL37_TX_CONFIG_MASK;
+ reg &= XGBE_AN_CL37_PCS_MODE_MASK;
+
+ switch (pdata->an_mode) {
+ case XGBE_AN_MODE_CL37:
+ reg |= XGBE_AN_CL37_PCS_MODE_BASEX;
+ break;
+ case XGBE_AN_MODE_CL37_SGMII:
+ reg |= XGBE_AN_CL37_PCS_MODE_SGMII;
+ break;
+ default:
+ break;
+ }
+
+ XMDIO_WRITE(pdata, MDIO_MMD_VEND2, MDIO_VEND2_AN_CTRL, reg);
+
+ netif_dbg(pdata, link, pdata->netdev, "CL37 AN (%s) initialized\n",
+ (pdata->an_mode == XGBE_AN_MODE_CL37) ? "BaseX" : "SGMII");
+}
+
static void xgbe_an73_init(struct xgbe_prv_data *pdata)
{
unsigned int reg;
@@ -719,6 +943,10 @@ static void xgbe_an_init(struct xgbe_prv_data *pdata)
case XGBE_AN_MODE_CL73:
xgbe_an73_init(pdata);
break;
+ case XGBE_AN_MODE_CL37:
+ case XGBE_AN_MODE_CL37_SGMII:
+ xgbe_an37_init(pdata);
+ break;
default:
break;
}
@@ -865,10 +1093,10 @@ static int __xgbe_phy_config_aneg(struct xgbe_prv_data *pdata)
}
/* Disable and stop any in progress auto-negotiation */
- xgbe_an_disable(pdata);
+ xgbe_an_disable_all(pdata);
/* Clear any auto-negotitation interrupts */
- xgbe_an73_clear_interrupts(pdata);
+ xgbe_an_clear_interrupts_all(pdata);
pdata->an_result = XGBE_AN_READY;
pdata->an_state = XGBE_AN_READY;
@@ -1007,7 +1235,7 @@ static void xgbe_phy_stop(struct xgbe_prv_data *pdata)
pdata->phy_started = 0;
/* Disable auto-negotiation */
- xgbe_an_disable(pdata);
+ xgbe_an_disable_all(pdata);
devm_free_irq(pdata->dev, pdata->an_irq, pdata);
@@ -1078,10 +1306,10 @@ static int xgbe_phy_reset(struct xgbe_prv_data *pdata)
return ret;
/* Disable auto-negotiation for now */
- xgbe_an_disable(pdata);
+ xgbe_an_disable_all(pdata);
/* Clear auto-negotiation interrupts */
- xgbe_an73_clear_interrupts(pdata);
+ xgbe_an_clear_interrupts_all(pdata);
return 0;
}
diff --git a/drivers/net/ethernet/amd/xgbe/xgbe.h b/drivers/net/ethernet/amd/xgbe/xgbe.h
index d90ecbc..8cb4f20 100644
--- a/drivers/net/ethernet/amd/xgbe/xgbe.h
+++ b/drivers/net/ethernet/amd/xgbe/xgbe.h
@@ -261,7 +261,13 @@
/* Auto-negotiation */
#define XGBE_AN_MS_TIMEOUT 500
-#define XGBE_LINK_TIMEOUT 10
+#define XGBE_LINK_TIMEOUT 5
+
+#define XGBE_SGMII_AN_LINK_STATUS BIT(1)
+#define XGBE_SGMII_AN_LINK_SPEED (BIT(2) | BIT(3))
+#define XGBE_SGMII_AN_LINK_SPEED_100 0x04
+#define XGBE_SGMII_AN_LINK_SPEED_1000 0x08
+#define XGBE_SGMII_AN_LINK_DUPLEX BIT(4)
struct xgbe_prv_data;
@@ -467,6 +473,8 @@ enum xgbe_speed {
enum xgbe_an_mode {
XGBE_AN_MODE_CL73 = 0,
+ XGBE_AN_MODE_CL37,
+ XGBE_AN_MODE_CL37_SGMII,
XGBE_AN_MODE_NONE,
};
@@ -961,6 +969,7 @@ struct xgbe_prv_data {
/* Auto-negotiation state machine support */
unsigned int an_int;
+ unsigned int an_status;
struct mutex an_mutex;
enum xgbe_an an_result;
enum xgbe_an an_state;
next prev parent reply other threads:[~2016-11-03 13:43 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-11-03 13:27 [PATCH net-next v1 00/21] amd-xgbe: AMD XGBE driver updates 2016-11-01 Tom Lendacky
2016-11-03 13:27 ` [PATCH net-next v1 01/21] amd-xgbe: Fix formatting of PCS register dump Tom Lendacky
2016-11-03 13:28 ` [PATCH net-next v1 02/21] amd-xgbe: Prepare for priority-based FIFO allocation Tom Lendacky
2016-11-03 13:51 ` Mintz, Yuval
2016-11-03 14:50 ` Tom Lendacky
2016-11-03 13:28 ` [PATCH net-next v1 03/21] amd-xgbe: Perform priority-based hardware " Tom Lendacky
2016-11-03 13:28 ` [PATCH net-next v1 04/21] amd-xgbe: Prepare for working with more than one type of phy Tom Lendacky
2016-11-03 13:28 ` [PATCH net-next v1 05/21] amd-xgbe: Prepare for introduction of clause 37 autoneg Tom Lendacky
2016-11-03 13:28 ` Tom Lendacky [this message]
2016-11-03 13:28 ` [PATCH net-next v1 07/21] amd-xgbe: Prepare for a new PCS register access method Tom Lendacky
2016-11-03 13:29 ` [PATCH net-next v1 08/21] amd-xgbe: Support for 64-bit management counter registers Tom Lendacky
2016-11-03 13:29 ` [PATCH net-next v1 09/21] amd-xgbe: Update how to determine DMA channel status Tom Lendacky
2016-11-03 13:29 ` [PATCH net-next v1 10/21] amd-xgbe: Prepare for supporting PCI devices Tom Lendacky
2016-11-03 13:29 ` [PATCH net-next v1 11/21] amd-xgbe: Guard against incorrectly generated interrupts Tom Lendacky
2016-11-03 13:29 ` [PATCH net-next v1 12/21] amd-xgbe: Add a workaround for Tx timestamp issue Tom Lendacky
2016-11-03 13:29 ` [PATCH net-next v1 13/21] amd-xgbe: Add PCI device support Tom Lendacky
2016-11-03 13:30 ` [PATCH net-next v1 14/21] amd-xgbe: Allow for a greater number of Rx queues Tom Lendacky
2016-11-03 13:30 ` [PATCH net-next v1 15/21] amd-xgbe: Add support for new DMA interrupt mode Tom Lendacky
2016-11-03 13:30 ` [PATCH net-next v1 16/21] amd-xgbe: Add ECC status support for the device memory Tom Lendacky
2016-11-03 13:30 ` [PATCH net-next v1 17/21] amd-xgbe: Add I2C support for determining SFP media types Tom Lendacky
2016-11-03 14:28 ` Andrew Lunn
2016-11-03 15:01 ` Tom Lendacky
2016-11-03 15:18 ` Andrew Lunn
2016-11-09 15:35 ` Tom Lendacky
2016-11-03 13:30 ` [PATCH net-next v1 18/21] net: phy: expose phy_aneg_done API for use by drivers Tom Lendacky
2016-11-04 2:13 ` kbuild test robot
2016-11-07 15:01 ` Tom Lendacky
2016-11-08 10:17 ` Andreas Larsson
2016-11-03 13:30 ` [PATCH net-next v1 19/21] amd-xgbe: Add support for SFP+ modules Tom Lendacky
2016-11-03 13:31 ` [PATCH net-next v1 20/21] amd-xgbe: Add support for MDIO attached PHYs Tom Lendacky
2016-11-03 13:31 ` [PATCH net-next v1 21/21] amd-xgbe: Add support for a KR redriver Tom Lendacky
2016-11-03 17:14 ` [PATCH net-next v1 00/21] amd-xgbe: AMD XGBE driver updates 2016-11-01 David Miller
2016-11-03 17:23 ` Tom Lendacky
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