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* [PATCH V1 1/2] arm64: dts: tegra210: Add SDMMC Auto-cal settings
@ 2018-12-18 19:19 Sowjanya Komatineni
  2018-12-18 19:19 ` [PATCH V1 2/2] mmc: tegra: SDMMC pads auto-calibration Sowjanya Komatineni
  0 siblings, 1 reply; 3+ messages in thread
From: Sowjanya Komatineni @ 2018-12-18 19:19 UTC (permalink / raw)
  To: robh+dt, mark.rutland, mperttunen, thierry.reding, jonathanh,
	adrian.hunter, ulf.hansson
  Cc: devicetree, linux-tegra, linux-kernel, linux-mmc, Sowjanya Komatineni

Add SDMMC initial pad offsets used by auto calibration process.

Add SDMMC fixed drive strengths used when calibration timeouts.
Fixed drive strengths are based on Pre SI Analysis of the pads.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 arch/arm64/boot/dts/nvidia/tegra186.dtsi |  2 ++
 arch/arm64/boot/dts/nvidia/tegra194.dtsi | 34 +++++++++++++++++++
 arch/arm64/boot/dts/nvidia/tegra210.dtsi | 57 ++++++++++++++++++++++++++++++--
 3 files changed, 91 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/nvidia/tegra186.dtsi b/arch/arm64/boot/dts/nvidia/tegra186.dtsi
index 2f3c8e29520d..0631bb9bfcc3 100644
--- a/arch/arm64/boot/dts/nvidia/tegra186.dtsi
+++ b/arch/arm64/boot/dts/nvidia/tegra186.dtsi
@@ -311,6 +311,8 @@
 		nvidia,pad-autocal-pull-down-offset-hs400 = <0x05>;
 		nvidia,pad-autocal-pull-up-offset-1v8-timeout = <0x0a>;
 		nvidia,pad-autocal-pull-down-offset-1v8-timeout = <0x0a>;
+		nvidia,pad-autocal-pull-up-offset-3v3-timeout = <0x0a>;
+		nvidia,pad-autocal-pull-down-offset-3v3-timeout = <0x0a>;
 		nvidia,default-tap = <0x5>;
 		nvidia,default-trim = <0x9>;
 		nvidia,dqs-trim = <63>;
diff --git a/arch/arm64/boot/dts/nvidia/tegra194.dtsi b/arch/arm64/boot/dts/nvidia/tegra194.dtsi
index c2091bb16546..3fab6802c335 100644
--- a/arch/arm64/boot/dts/nvidia/tegra194.dtsi
+++ b/arch/arm64/boot/dts/nvidia/tegra194.dtsi
@@ -301,6 +301,17 @@
 			clock-names = "sdhci";
 			resets = <&bpmp TEGRA194_RESET_SDMMC1>;
 			reset-names = "sdhci";
+			nvidia,pad-autocal-pull-up-offset-3v3-timeout =
+									<0x07>;
+			nvidia,pad-autocal-pull-down-offset-3v3-timeout =
+									<0x07>;
+			nvidia,pad-autocal-pull-up-offset-1v8-timeout = <0x06>;
+			nvidia,pad-autocal-pull-down-offset-1v8-timeout =
+									<0x07>;
+			nvidia,pad-autocal-pull-up-offset-sdr104 = <0x00>;
+			nvidia,pad-autocal-pull-down-offset-sdr104 = <0x00>;
+			nvidia,default-tap = <0x9>;
+			nvidia,default-trim = <0x5>;
 			status = "disabled";
 		};
 
@@ -312,6 +323,18 @@
 			clock-names = "sdhci";
 			resets = <&bpmp TEGRA194_RESET_SDMMC3>;
 			reset-names = "sdhci";
+			nvidia,pad-autocal-pull-up-offset-1v8 = <0x00>;
+			nvidia,pad-autocal-pull-down-offset-1v8 = <0x7a>;
+			nvidia,pad-autocal-pull-up-offset-3v3-timeout = <0x07>;
+			nvidia,pad-autocal-pull-down-offset-3v3-timeout =
+									<0x07>;
+			nvidia,pad-autocal-pull-up-offset-1v8-timeout = <0x06>;
+			nvidia,pad-autocal-pull-down-offset-1v8-timeout =
+									<0x07>;
+			nvidia,pad-autocal-pull-up-offset-sdr104 = <0x00>;
+			nvidia,pad-autocal-pull-down-offset-sdr104 = <0x00>;
+			nvidia,default-tap = <0x9>;
+			nvidia,default-trim = <0x5>;
 			status = "disabled";
 		};
 
@@ -323,6 +346,17 @@
 			clock-names = "sdhci";
 			resets = <&bpmp TEGRA194_RESET_SDMMC4>;
 			reset-names = "sdhci";
+			nvidia,pad-autocal-pull-up-offset-hs400 = <0x00>;
+			nvidia,pad-autocal-pull-down-offset-hs400 = <0x00>;
+			nvidia,pad-autocal-pull-up-offset-1v8-timeout = <0x0a>;
+			nvidia,pad-autocal-pull-down-offset-1v8-timeout =
+									<0x0a>;
+			nvidia,pad-autocal-pull-up-offset-3v3-timeout = <0x0a>;
+			nvidia,pad-autocal-pull-down-offset-3v3-timeout =
+									<0x0a>;
+			nvidia,default-tap = <0x8>;
+			nvidia,default-trim = <0x14>;
+			nvidia,dqs-trim = <40>;
 			status = "disabled";
 		};
 
diff --git a/arch/arm64/boot/dts/nvidia/tegra210.dtsi b/arch/arm64/boot/dts/nvidia/tegra210.dtsi
index 2205d66b0443..41408df9d4e9 100644
--- a/arch/arm64/boot/dts/nvidia/tegra210.dtsi
+++ b/arch/arm64/boot/dts/nvidia/tegra210.dtsi
@@ -476,6 +476,48 @@
 		compatible = "nvidia,tegra210-pinmux";
 		reg = <0x0 0x700008d4 0x0 0x29c>, /* Pad control registers */
 		      <0x0 0x70003000 0x0 0x294>; /* Mux registers */
+		sdmmc1_3v3_drv: sdmmc1-3v3-drv {
+			sdmmc1 {
+				nvidia,pins = "drive_sdmmc1";
+				nvidia,pull-down-strength = <0x8>;
+				nvidia,pull-up-strength = <0x8>;
+			};
+		};
+		sdmmc1_1v8_drv: sdmmc1-1v8-drv {
+			sdmmc1 {
+				nvidia,pins = "drive_sdmmc1";
+				nvidia,pull-down-strength = <0x4>;
+				nvidia,pull-up-strength = <0x3>;
+			};
+		};
+		sdmmc2_1v8_drv: sdmmc2-1v8-drv {
+			sdmmc2 {
+				nvidia,pins = "drive_sdmmc2";
+				nvidia,pull-down-strength = <0x10>;
+				nvidia,pull-up-strength = <0x10>;
+			};
+		};
+		sdmmc3_3v3_drv: sdmmc3-3v3-drv {
+			sdmmc3 {
+				nvidia,pins = "drive_sdmmc3";
+				nvidia,pull-down-strength = <0x8>;
+				nvidia,pull-up-strength = <0x8>;
+			};
+		};
+		sdmmc3_1v8_drv: sdmmc3-1v8-drv {
+			sdmmc3 {
+				nvidia,pins = "drive_sdmmc3";
+				nvidia,pull-down-strength = <0x4>;
+				nvidia,pull-up-strength = <0x3>;
+			};
+		};
+		sdmmc4_1v8_drv: sdmmc4-1v8-drv {
+			sdmmc4 {
+				nvidia,pins = "drive_sdmmc4";
+				nvidia,pull-down-strength = <0x10>;
+				nvidia,pull-up-strength = <0x10>;
+			};
+		};
 	};
 
 	/*
@@ -1050,9 +1092,12 @@
 		clock-names = "sdhci";
 		resets = <&tegra_car 14>;
 		reset-names = "sdhci";
-		pinctrl-names = "sdmmc-3v3", "sdmmc-1v8";
+		pinctrl-names = "sdmmc-3v3", "sdmmc-1v8",
+				"sdmmc-3v3-drv", "sdmmc-1v8-drv";
 		pinctrl-0 = <&sdmmc1_3v3>;
 		pinctrl-1 = <&sdmmc1_1v8>;
+		pinctrl-2 = <&sdmmc1_3v3_drv>;
+		pinctrl-3 = <&sdmmc1_1v8_drv>;
 		nvidia,pad-autocal-pull-up-offset-3v3 = <0x00>;
 		nvidia,pad-autocal-pull-down-offset-3v3 = <0x7d>;
 		nvidia,pad-autocal-pull-up-offset-1v8 = <0x7b>;
@@ -1075,6 +1120,8 @@
 		clock-names = "sdhci";
 		resets = <&tegra_car 9>;
 		reset-names = "sdhci";
+		pinctrl-names = "sdmmc-1v8-drv";
+		pinctrl-0 = <&sdmmc2_1v8_drv>;
 		nvidia,pad-autocal-pull-up-offset-1v8 = <0x05>;
 		nvidia,pad-autocal-pull-down-offset-1v8 = <0x05>;
 		nvidia,default-tap = <0x8>;
@@ -1090,9 +1137,12 @@
 		clock-names = "sdhci";
 		resets = <&tegra_car 69>;
 		reset-names = "sdhci";
-		pinctrl-names = "sdmmc-3v3", "sdmmc-1v8";
+		pinctrl-names = "sdmmc-3v3", "sdmmc-1v8",
+				"sdmmc-3v3-drv", "sdmmc-1v8-drv";
 		pinctrl-0 = <&sdmmc3_3v3>;
 		pinctrl-1 = <&sdmmc3_1v8>;
+		pinctrl-2 = <&sdmmc3_3v3_drv>;
+		pinctrl-3 = <&sdmmc3_1v8_drv>;
 		nvidia,pad-autocal-pull-up-offset-3v3 = <0x00>;
 		nvidia,pad-autocal-pull-down-offset-3v3 = <0x7d>;
 		nvidia,pad-autocal-pull-up-offset-1v8 = <0x7b>;
@@ -1110,6 +1160,9 @@
 		clock-names = "sdhci";
 		resets = <&tegra_car 15>;
 		reset-names = "sdhci";
+		pinctrl-names = "sdmmc-3v3-drv", "sdmmc-1v8-drv";
+		pinctrl-0 = <&sdmmc4_1v8_drv>;
+		pinctrl-1 = <&sdmmc4_1v8_drv>;
 		nvidia,pad-autocal-pull-up-offset-1v8 = <0x05>;
 		nvidia,pad-autocal-pull-down-offset-1v8 = <0x05>;
 		nvidia,default-tap = <0x8>;
-- 
2.7.4


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* [PATCH V1 2/2] mmc: tegra: SDMMC pads auto-calibration
  2018-12-18 19:19 [PATCH V1 1/2] arm64: dts: tegra210: Add SDMMC Auto-cal settings Sowjanya Komatineni
@ 2018-12-18 19:19 ` Sowjanya Komatineni
  2018-12-19 11:39   ` Ulf Hansson
  0 siblings, 1 reply; 3+ messages in thread
From: Sowjanya Komatineni @ 2018-12-18 19:19 UTC (permalink / raw)
  To: robh+dt, mark.rutland, mperttunen, thierry.reding, jonathanh,
	adrian.hunter, ulf.hansson
  Cc: devicetree, linux-tegra, linux-kernel, linux-mmc, Sowjanya Komatineni

Programs initial drive code offsets which will be used by auto
calibration process.

Programs fixed drive strengths for SDMMC pads when auto cal
timeouts. Fixed settings are based on Pre-SI analysis of the
pad design.

Signed-off-by: Sowjanya Komatineni <skomatineni@nvidia.com>
---
 drivers/mmc/host/sdhci-tegra.c | 112 ++++++++++++++++++++++++++++++-----------
 1 file changed, 84 insertions(+), 28 deletions(-)

diff --git a/drivers/mmc/host/sdhci-tegra.c b/drivers/mmc/host/sdhci-tegra.c
index 7b95d088fdef..2524654282d1 100644
--- a/drivers/mmc/host/sdhci-tegra.c
+++ b/drivers/mmc/host/sdhci-tegra.c
@@ -75,6 +75,7 @@
 #define SDHCI_TEGRA_SDMEM_COMP_PADCTRL_VREF_SEL_MASK	0x0000000f
 #define SDHCI_TEGRA_SDMEM_COMP_PADCTRL_VREF_SEL_VAL	0x7
 #define SDHCI_TEGRA_SDMEM_COMP_PADCTRL_E_INPUT_E_PWRD	BIT(31)
+#define SDHCI_COMP_PADCTRL_DRVUPDN_OFFSET_MASK		0x07FFF000
 
 #define SDHCI_TEGRA_AUTO_CAL_STATUS			0x1ec
 #define SDHCI_TEGRA_AUTO_CAL_ACTIVE			BIT(31)
@@ -121,6 +122,8 @@ struct sdhci_tegra {
 	struct pinctrl *pinctrl_sdmmc;
 	struct pinctrl_state *pinctrl_state_3v3;
 	struct pinctrl_state *pinctrl_state_1v8;
+	struct pinctrl_state *pinctrl_state_3v3_drv;
+	struct pinctrl_state *pinctrl_state_1v8_drv;
 
 	struct sdhci_tegra_autocal_offsets autocal_offsets;
 	ktime_t last_calib;
@@ -130,6 +133,9 @@ struct sdhci_tegra {
 	u32 dqs_trim;
 };
 
+static int tegra_sdhci_set_padctrl(struct sdhci_host *host, int voltage,
+							bool state_drvupdn);
+
 static u16 tegra_sdhci_readw(struct sdhci_host *host, int reg)
 {
 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
@@ -437,6 +443,7 @@ static void tegra_sdhci_pad_autocalib(struct sdhci_host *host)
 			pdpu = offsets.pull_down_3v3 << 8 | offsets.pull_up_3v3;
 	}
 
+	/* Set initial offset before auto-calibration */
 	tegra_sdhci_set_pad_autocal_offset(host, pdpu);
 
 	card_clk_enabled = tegra_sdhci_configure_card_clk(host, false);
@@ -460,19 +467,15 @@ static void tegra_sdhci_pad_autocalib(struct sdhci_host *host)
 	if (ret) {
 		dev_err(mmc_dev(host->mmc), "Pad autocal timed out\n");
 
-		if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_180)
-			pdpu = offsets.pull_down_1v8_timeout << 8 |
-			       offsets.pull_up_1v8_timeout;
-		else
-			pdpu = offsets.pull_down_3v3_timeout << 8 |
-			       offsets.pull_up_3v3_timeout;
-
-		/* Disable automatic calibration and use fixed offsets */
+		/* Disable automatic cal and use fixed Drive Strengths */
 		reg = sdhci_readl(host, SDHCI_TEGRA_AUTO_CAL_CONFIG);
 		reg &= ~SDHCI_AUTO_CAL_ENABLE;
 		sdhci_writel(host, reg, SDHCI_TEGRA_AUTO_CAL_CONFIG);
 
-		tegra_sdhci_set_pad_autocal_offset(host, pdpu);
+		ret = tegra_sdhci_set_padctrl(host, ios->signal_voltage, false);
+		if (ret < 0)
+			dev_err(mmc_dev(host->mmc),
+			"Setting drive strengths failed %d\n", PTR_ERR(ret));
 	}
 }
 
@@ -743,27 +746,73 @@ static int tegra_sdhci_execute_tuning(struct sdhci_host *host, u32 opcode)
 	return mmc_send_tuning(host->mmc, opcode, NULL);
 }
 
-static int tegra_sdhci_set_padctrl(struct sdhci_host *host, int voltage)
+static int tegra_sdhci_set_padctrl(struct sdhci_host *host, int voltage,
+							bool state_drvupdn)
 {
 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 	struct sdhci_tegra *tegra_host = sdhci_pltfm_priv(pltfm_host);
-	int ret;
+	struct sdhci_tegra_autocal_offsets offsets =
+					tegra_host->autocal_offsets;
+	struct pinctrl_state *pinctrl_drvupdn = NULL;
+	int ret = 0;
+	u8 drvup = 0, drvdn = 0;
+	u32 reg;
 
-	if (!tegra_host->pad_control_available)
-		return 0;
+	if (!state_drvupdn) {
+		/* PADS Drive Strength */
+		if (voltage == MMC_SIGNAL_VOLTAGE_180) {
+			if (!IS_ERR(tegra_host->pinctrl_state_1v8_drv) &&
+				(tegra_host->pinctrl_state_1v8_drv != NULL)) {
+				pinctrl_drvupdn =
+					tegra_host->pinctrl_state_1v8_drv;
+			} else {
+				drvup = offsets.pull_up_1v8_timeout;
+				drvdn = offsets.pull_down_1v8_timeout;
+			}
+		} else {
+			if (!IS_ERR(tegra_host->pinctrl_state_3v3_drv) &&
+				(tegra_host->pinctrl_state_3v3_drv != NULL)) {
+				pinctrl_drvupdn =
+					tegra_host->pinctrl_state_3v3_drv;
+			} else {
+				drvup = offsets.pull_up_3v3_timeout;
+				drvdn = offsets.pull_down_3v3_timeout;
+			}
+		}
+
+		if (pinctrl_drvupdn != NULL) {
+			ret = pinctrl_select_state(tegra_host->pinctrl_sdmmc,
+							pinctrl_drvupdn);
+			if (ret < 0)
+				dev_err(mmc_dev(host->mmc),
+					"failed pads drvupdn, ret: %d\n", ret);
+		} else if ((drvup) || (drvdn)) {
+			reg = sdhci_readl(host,
+					SDHCI_TEGRA_SDMEM_COMP_PADCTRL);
+			reg &= ~SDHCI_COMP_PADCTRL_DRVUPDN_OFFSET_MASK;
+			reg |= (drvup << 20) | (drvdn << 12);
+			sdhci_writel(host, reg,
+					SDHCI_TEGRA_SDMEM_COMP_PADCTRL);
+		}
 
-	if (voltage == MMC_SIGNAL_VOLTAGE_180) {
-		ret = pinctrl_select_state(tegra_host->pinctrl_sdmmc,
-					   tegra_host->pinctrl_state_1v8);
-		if (ret < 0)
-			dev_err(mmc_dev(host->mmc),
-				"setting 1.8V failed, ret: %d\n", ret);
 	} else {
-		ret = pinctrl_select_state(tegra_host->pinctrl_sdmmc,
-					   tegra_host->pinctrl_state_3v3);
-		if (ret < 0)
-			dev_err(mmc_dev(host->mmc),
-				"setting 3.3V failed, ret: %d\n", ret);
+		/* Dual Voltage PADS Voltage selection */
+		if (!tegra_host->pad_control_available)
+			return 0;
+
+		if (voltage == MMC_SIGNAL_VOLTAGE_180) {
+			ret = pinctrl_select_state(tegra_host->pinctrl_sdmmc,
+						tegra_host->pinctrl_state_1v8);
+			if (ret < 0)
+				dev_err(mmc_dev(host->mmc),
+					"setting 1.8V failed, ret: %d\n", ret);
+		} else {
+			ret = pinctrl_select_state(tegra_host->pinctrl_sdmmc,
+						tegra_host->pinctrl_state_3v3);
+			if (ret < 0)
+				dev_err(mmc_dev(host->mmc),
+					"setting 3.3V failed, ret: %d\n", ret);
+		}
 	}
 
 	return ret;
@@ -778,7 +827,7 @@ static int sdhci_tegra_start_signal_voltage_switch(struct mmc_host *mmc,
 	int ret = 0;
 
 	if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_330) {
-		ret = tegra_sdhci_set_padctrl(host, ios->signal_voltage);
+		ret = tegra_sdhci_set_padctrl(host, ios->signal_voltage, true);
 		if (ret < 0)
 			return ret;
 		ret = sdhci_start_signal_voltage_switch(mmc, ios);
@@ -786,7 +835,7 @@ static int sdhci_tegra_start_signal_voltage_switch(struct mmc_host *mmc,
 		ret = sdhci_start_signal_voltage_switch(mmc, ios);
 		if (ret < 0)
 			return ret;
-		ret = tegra_sdhci_set_padctrl(host, ios->signal_voltage);
+		ret = tegra_sdhci_set_padctrl(host, ios->signal_voltage, true);
 	}
 
 	if (tegra_host->pad_calib_required)
@@ -805,8 +854,15 @@ static int tegra_sdhci_init_pinctrl_info(struct device *dev,
 		return -1;
 	}
 
-	tegra_host->pinctrl_state_3v3 =
-		pinctrl_lookup_state(tegra_host->pinctrl_sdmmc, "sdmmc-3v3");
+	tegra_host->pinctrl_state_1v8_drv = pinctrl_lookup_state(
+				tegra_host->pinctrl_sdmmc, "sdmmc-1v8-drv");
+
+	tegra_host->pinctrl_state_3v3_drv = pinctrl_lookup_state(
+				tegra_host->pinctrl_sdmmc, "sdmmc-3v3-drv");
+
+	tegra_host->pinctrl_state_3v3 = pinctrl_lookup_state(
+				tegra_host->pinctrl_sdmmc, "sdmmc-3v3");
+
 	if (IS_ERR(tegra_host->pinctrl_state_3v3)) {
 		dev_warn(dev, "Missing 3.3V pad state, err: %ld\n",
 			 PTR_ERR(tegra_host->pinctrl_state_3v3));
-- 
2.7.4


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH V1 2/2] mmc: tegra: SDMMC pads auto-calibration
  2018-12-18 19:19 ` [PATCH V1 2/2] mmc: tegra: SDMMC pads auto-calibration Sowjanya Komatineni
@ 2018-12-19 11:39   ` Ulf Hansson
  0 siblings, 0 replies; 3+ messages in thread
From: Ulf Hansson @ 2018-12-19 11:39 UTC (permalink / raw)
  To: Sowjanya Komatineni
  Cc: Rob Herring, Mark Rutland, Mikko Perttunen, Thierry Reding,
	Jon Hunter, Adrian Hunter, DTML, linux-tegra,
	Linux Kernel Mailing List, linux-mmc

[...]

>         if (tegra_host->pad_calib_required)
> @@ -805,8 +854,15 @@ static int tegra_sdhci_init_pinctrl_info(struct device *dev,
>                 return -1;
>         }
>
> -       tegra_host->pinctrl_state_3v3 =
> -               pinctrl_lookup_state(tegra_host->pinctrl_sdmmc, "sdmmc-3v3");
> +       tegra_host->pinctrl_state_1v8_drv = pinctrl_lookup_state(
> +                               tegra_host->pinctrl_sdmmc, "sdmmc-1v8-drv");

This requires and updated DT doc for tegra sdhci. Please make that a
separate patch and put it first in the series. Also don't forget to
include the DT maintainers in the to field for that patch.

> +
> +       tegra_host->pinctrl_state_3v3_drv = pinctrl_lookup_state(
> +                               tegra_host->pinctrl_sdmmc, "sdmmc-3v3-drv");

Ditto.

> +
> +       tegra_host->pinctrl_state_3v3 = pinctrl_lookup_state(
> +                               tegra_host->pinctrl_sdmmc, "sdmmc-3v3");
> +

The above looks like an unnecessary line change. Please just stick to
the existing format and avoid changing code that doesn't need to be
changed.

>         if (IS_ERR(tegra_host->pinctrl_state_3v3)) {
>                 dev_warn(dev, "Missing 3.3V pad state, err: %ld\n",
>                          PTR_ERR(tegra_host->pinctrl_state_3v3));
> --
> 2.7.4
>

Kind regards
Uffe

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2018-12-19 11:39 UTC | newest]

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2018-12-18 19:19 [PATCH V1 1/2] arm64: dts: tegra210: Add SDMMC Auto-cal settings Sowjanya Komatineni
2018-12-18 19:19 ` [PATCH V1 2/2] mmc: tegra: SDMMC pads auto-calibration Sowjanya Komatineni
2018-12-19 11:39   ` Ulf Hansson

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