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From: Ryder Lee <ryder.lee@mediatek.com>
To: u-boot@lists.denx.de
Subject: [U-Boot] [PATCH 3/4] pci: mediatek: Add pci-driver for mt2701
Date: Wed, 31 Jul 2019 23:23:08 +0800	[thread overview]
Message-ID: <1564586588.18587.14.camel@mtkswgap22> (raw)
In-Reply-To: <1564583732.16285.17.camel@mtkswgap22>

On Wed, 2019-07-31 at 22:35 +0800, Ryder Lee wrote:
> On Wed, 2019-07-31 at 17:13 +0300, Aleksandr Rybalko wrote:
> > Hello Ryder.
> > 
> > 
> > ср, 31 лип. 2019 о 15:45 Ryder Lee <ryder.lee@mediatek.com> пише:
> > 
> >         + GSS_MTK_Uboot_upstream <GSS_MTK_Uboot_upstream@mediatek.com>
> >         
> >         On Wed, 2019-07-31 at 13:51 +0200, Frank Wunderlich wrote:
> >         > From: Oleksandr Rybalko <ray@ddteam.net>
> >         > 
> >         > this chip is used in MT7623 and some other Mediatek SoCs for
> >         pcie
> >         > 
> >         > Tested-by: Frank Wunderlich <frank-w@public-files.de>
> >         > Signed-off-by: Frank Wunderlich <frank-w@public-files.de>
> >         > Signed-off-by: Oleksandr Rybalko <ray@ddteam.net>
> >         > ---
> >         >  drivers/pci/Kconfig      |   6 +
> >         >  drivers/pci/Makefile     |   1 +
> >         >  drivers/pci/pci-mt2701.c | 490
> >         +++++++++++++++++++++++++++++++++++++++
> >         >  3 files changed, 497 insertions(+)
> >         >  create mode 100644 drivers/pci/pci-mt2701.c
> >         
> >         Rename 'pci-mt2701.c' to 'pcie-mediatek.c' and then change the
> >         subject.
> > 
> > 
> > So you promise us, that Mediatek will never produce PCI-E controller
> > which will be totally different from that one? :)
> 
> imho we can use single driver for different IP generation and that is
> what we did in linux now.
> 
> MT7623/MT2701 - mtk_pcie_soc_v1
> MT7622/MT7629 - v2
> gen3 IP - TBD
> >  
> >         
> >         Obviously, this is an intermediate version of Linux patch, so
> >         I suggest
> >         to take a look at the latest version of vanilla Kernel:
> >         https://github.com/torvalds/linux/blob/master/drivers/pci/controller/pcie-mediatek.c
> >         
> >         Please see my comments inline: 
> >         
> >         > diff --git a/drivers/pci/Kconfig b/drivers/pci/Kconfig
> >         > index 3fe38f7315..cfe8ba5e52 100644
> >         > --- a/drivers/pci/Kconfig
> >         > +++ b/drivers/pci/Kconfig
> >         > @@ -145,4 +145,10 @@ config PCI_MVEBU
> >         >         Say Y here if you want to enable PCIe controller
> >         support on
> >         >         Armada XP/38x SoCs.
> >         > 
> >         > +config PCIE_MT2701
> >         > +     bool "Mediatek 2701 PCI-E"
> >         > +     help
> >         > +       Say Y here if you want to enable PCIe controller
> >         support on
> >         > +       Mediatek MT7623
> >         > +
> >         >  endif
> >         > diff --git a/drivers/pci/Makefile b/drivers/pci/Makefile
> >         > index b5ebd50c85..a4c4002b9c 100644
> >         > --- a/drivers/pci/Makefile
> >         > +++ b/drivers/pci/Makefile
> >         > @@ -38,3 +38,4 @@ obj-$(CONFIG_PCIE_LAYERSCAPE_GEN4) +=
> >         pcie_layerscape_gen4.o \
> >         >                               pcie_layerscape_gen4_fixup.o
> >         >  obj-$(CONFIG_PCI_XILINX) += pcie_xilinx.o
> >         >  obj-$(CONFIG_PCIE_INTEL_FPGA) += pcie_intel_fpga.o
> >         > +obj-$(CONFIG_PCIE_MT2701) += pci-mt2701.o
> >         > diff --git a/drivers/pci/pci-mt2701.c
> >         b/drivers/pci/pci-mt2701.c
> >         > new file mode 100644
> >         > index 0000000000..5904f15330
> >         > --- /dev/null
> >         > +++ b/drivers/pci/pci-mt2701.c
> >         > @@ -0,0 +1,490 @@
> >         > +// SPDX-License-Identifier: GPL-2.0+
> >         > +/*
> >         > + *  Mediatek MT7623 SoC PCIE support
> >         > + *
> >         > + *  Copyright (C) 2015 Mediatek
> >         > + *  Copyright (C) 2015 John Crispin <blogic@openwrt.org>
> >         > + *  Copyright (C) 2015 Ziv Huang <ziv.huang@mediatek.com>
> >         > + *  Copyright (C) 2019 Oleksandr Rybalko <ray@ddteam.net>
> >         > + */
> >         > +
> >         > +#include <common.h>
> >         > +#include <malloc.h>
> >         > +
> >         > +#include <pci.h>
> >         > +#include <asm/io.h>
> >         > +
> >         > +#include <dm.h>
> >         > +#include <fdtdec.h>
> >         > +#include <linux/libfdt.h>
> >         > +#include <dm/lists.h>
> >         > +
> >         > +#define iowrite32(v, a)      writel(v, a)
> >         > +#define iowrite16(v, a)      writew(v, a)
> >         > +#define iowrite8(v, a)       writeb(v, a)
> >         > +#define ioread32(a)  readl(a)
> >         > +#define ioread16(a)  readw(a)
> >         > +#define ioread8(a)   readb(a)
> >         
> >         Remove these defines.
> >         
> >         > +#define RT_HIFSYS_BASE               0x1a000000
> >         > +#define RT_PCIE_BASE         0x1a140000
> >         > +#define RT_PCIE_IOWIN_BASE   0x1a160000
> >         > +#define RT_PCIE_IOWIN_SIZE   0x00010000
> >         > +#define RT_PCIE_MEMWIN_BASE  0x60000000
> >         > +#define RT_PCIE_MEMWIN_SIZE  0x10000000
> >         
> >         Move these base to dts.
> > 
> > 
> > Already there (ranges), just not used yet.
> 
> so it's better remove unused parts, right?
> >         
> >         > +#define RD(x)                readl(RT_PCIE_BASE | (x))
> >         > +#define WR(x, v)     writel(v, RT_PCIE_BASE | (x))
> >         > +
> >         > +#define SYSCFG1                      0x14
> >         > +#define RSTCTL                       0x34
> >         > +#define RSTSTAT                      0x38
> >         > +#define PCICFG                       0x00
> >         > +#define PCIINT                       0x08
> >         > +#define PCIENA                       0x0c
> >         > +#define CFGADDR                      0x20
> >         > +#define CFGDATA                      0x24
> >         > +#define MEMBASE                      0x28
> >         > +#define IOBASE                       0x2c
> >         > +
> >         > +#define BAR0SETUP            0x10
> >         > +#define IMBASEBAR0           0x18
> >         > +#define PCIE_CLASS           0x34
> >         > +#define PCIE_SISTAT          0x50
> >         > +
> >         > +#define MTK_PCIE_HIGH_PERF   BIT(14)
> >         > +#define PCIEP0_BASE          0x2000
> >         > +#define PCIEP1_BASE          0x3000
> >         > +#define PCIEP2_BASE          0x4000
> >         > +
> >         > +#define PHY_P0_CTL           0x9000
> >         > +#define PHY_P1_CTL           0xa000
> >         > +#define PHY_P2_CTL           0x4000 /* in USB space */
> >         > +
> >         > +#define RSTCTL_PCIE0_RST     BIT(24)
> >         > +#define RSTCTL_PCIE1_RST     BIT(25)
> >         > +#define RSTCTL_PCIE2_RST     BIT(26)
> >         > +#define MAX_PORT_NUM         3
> >         > +
> >         > +struct resource {
> >         > +     char *name;
> >         > +     u32 start;
> >         > +     u32 end;
> >         > +};
> >         > +
> >         > +struct mt_pcie {
> >         > +     char name[16];
> >         > +};
> >         > +
> >         > +static struct mtk_pcie_port {
> >         > +     int id;
> >         > +     int enable;
> >         > +     u32 base;
> >         > +     u32 phy_base;
> >         > +     u32 perst_n;
> >         > +     u32 reset;
> >         > +     u32 interrupt_en;
> >         > +     int irq;
> >         > +     u32 link;
> >         > +} mtk_pcie_port[] = {
> >         > +     { 0, 1, PCIEP0_BASE, PHY_P0_CTL, BIT(1),
> >         RSTCTL_PCIE0_RST, BIT(20) },
> >         > +     { 1, 1, PCIEP1_BASE, PHY_P1_CTL, BIT(2),
> >         RSTCTL_PCIE1_RST, BIT(21) },
> >         > +     { 2, 0, PCIEP2_BASE, PHY_P2_CTL, BIT(3),
> >         RSTCTL_PCIE2_RST, BIT(22) },
> >         > +};
> >         
> >         move some of mtk_pcie_port[] to dts.
> > 
> > 
> > Main point, at the end use orginal linux kernel DTS files. So it can
> > be passed into kernel, instead of hardcode it inside kernel.
> > 
> > Just like we have ACPI blob on PC.
> > 
> From what I see "[PATCH 4/4] arm: dts: Add PCI-E controller for mt7623"
> has enough information about "base/offset/port/phy" (that dts is same as
> linux one), but this driver does not use them.
> >         
> >         > +struct mtk_pcie {
> >         > +     struct device *dev;
> >         > +     void __iomem *sys_base;         /* HIF SYSCTL
> >         registers */
> >         > +     void __iomem *pcie_base;        /* PCIE registers */
> >         > +     void __iomem *usb_base;         /* USB registers */
> >         > +
> >         > +     struct resource io;
> >         > +     struct resource pio;
> >         > +     struct resource mem;
> >         > +     struct resource prefetch;
> >         > +     struct resource busn;
> >         > +
> >         > +     u32 io_bus_addr;
> >         > +     u32 mem_bus_addr;
> >         > +
> >         > +     struct clk *clk;
> >         > +     int pcie_card_link;
> >         > +};
> >         > +
> >         > +static const struct mtk_phy_init {
> >         > +     u32 reg;
> >         > +     u32 mask;
> >         > +     u32 val;
> >         > +} mtk_phy_init[] = {
> >         > +     { 0xc00, 0x33000, 0x22000 },
> >         > +     { 0xb04, 0xe0000000, 0x40000000 },
> >         > +     { 0xb00, 0xe, 0x4 },
> >         > +     { 0xc3C, 0xffff0000, 0x3c0000 },
> >         > +     { 0xc48, 0xffff, 0x36 },
> >         > +     { 0xc0c, 0x30000000, 0x10000000 },
> >         > +     { 0xc08, 0x3800c0, 0xc0 },
> >         > +     { 0xc10, 0xf0000, 0x20000 },
> >         > +     { 0xc0c, 0xf000, 0x1000 },
> >         > +     { 0xc14, 0xf0000, 0xa0000 },
> >         > +     { 0xa28, 0x3fe00, 0x2000 },
> >         > +     { 0xa2c, 0x1ff, 0x10 },
> >         > +};
> >         
> >         We should add another PHY driver (drivers/phy/) for these
> >         settings.
> >         Like what we did for Linux:
> >         https://github.com/torvalds/linux/blob/master/drivers/phy/mediatek/phy-mtk-tphy.c
> >         
> > 
> > 
> > Yes, but it more complex way for future releases.
> > 
> phy driver is used for configuring basic settings, there is no complex
> logic in it. we can even copy and paste the entire block from that
> driver.
> 
> .version = MTK_PHY_V1
> case PHY_TYPE_PCIE:
> 	pcie_phy_instance_init(tphy, instance);
> 
> 
> >         > +/*
> >         > + * Globals.
> >         > + */
> >         > +
> >         > +struct mtk_pcie pcie;
> >         > +struct mtk_pcie *pcie0;
> >         > +
> >         > +static int mtk_pcie_probe(void);
> >         > +static int mt_pcie_read_config(struct udevice *, pci_dev_t,
> >         uint, ulong *,
> >         > +                            enum pci_size_t);
> >         > +static int mt_pcie_write_config(struct udevice *,
> >         pci_dev_t, uint, ulong,
> >         > +                             enum pci_size_t);
> >         > +
> >         > +#define mtk_foreach_port(p)          \
> >         > +             for ((p) = mtk_pcie_port;       \
> >         > +             (p) !=
> >         &mtk_pcie_port[ARRAY_SIZE(mtk_pcie_port)]; (p)++)
> >         
> >         Use dts for each port.
> >         
> >         > +#define BITS(m, n)   (~(BIT(m) - 1) & ((BIT(n) - 1) |
> >         BIT(n)))
> >         > +
> >         > +static void
> >         > +mt7623_pcie_pinmux_set(void)
> >         > +{
> >         > +     u32 regValue;
> >         > +
> >         > +     /* Pin208: PCIE0_PERST_N (3) */
> >         > +     regValue = le32_to_cpu(ioread32(0x100059f0));
> >         > +     regValue &= ~(BITS(9, 11));
> >         > +     regValue |= 3 << 9;
> >         > +     iowrite32(regValue, 0x100059f0);
> >         > +
> >         > +     /* Pin208: PCIE1_PERST_N (3) */
> >         > +     regValue = le32_to_cpu(ioread32(0x100059f0));
> >         > +     regValue &= ~(BITS(12, 14));
> >         > +     regValue |= 3 << 12;
> >         > +     iowrite32(regValue, 0x100059f0);
> >         > +}
> >         
> >         Configure pinmux in dts.
> > Will be, when we reach point of full tree.
> 
> now we have mt7623 pinctrl driver that should be enough.
> 
> >         > +static void
> >         > +sys_w32(struct mtk_pcie *pcie, u32 val, unsigned int reg)
> >         > +{
> >         > +     iowrite32(val, pcie->sys_base + reg);
> >         > +}
> >         > +
> >         > +static u32
> >         > +sys_r32(struct mtk_pcie *pcie, unsigned int reg)
> >         > +{
> >         > +     return ioread32(pcie->sys_base + reg);
> >         > +}
> >         > +
> >         > +static void
> >         > +pcie_w32(struct mtk_pcie *pcie, u32 val, unsigned int reg)
> >         > +{
> >         > +     iowrite32(val, pcie->pcie_base + reg);
> >         > +}
> >         > +
> >         > +static void
> >         > +pcie_w16(struct mtk_pcie *pcie, u16 val, unsigned int reg)
> >         > +{
> >         > +     iowrite16(val, pcie->pcie_base + reg);
> >         > +}
> >         > +
> >         > +static void
> >         > +pcie_w8(struct mtk_pcie *pcie, u8 val, unsigned int reg)
> >         > +{
> >         > +     iowrite8(val, pcie->pcie_base + reg);
> >         > +}
> >         > +
> >         > +static u32
> >         > +pcie_r32(struct mtk_pcie *pcie, unsigned int reg)
> >         > +{
> >         > +     return ioread32(pcie->pcie_base + reg);
> >         > +}
> >         > +
> >         > +static u32
> >         > +pcie_r16(struct mtk_pcie *pcie, unsigned int reg)
> >         > +{
> >         > +     return ioread16(pcie->pcie_base + reg);
> >         > +}
> >         > +
> >         > +static u32
> >         > +pcie_r8(struct mtk_pcie *pcie, unsigned int reg)
> >         > +{
> >         > +     return ioread8(pcie->pcie_base + reg);
> >         > +}

More specifically, we should use pci_generic_mmap_write/read_config()
for standard set of confi read/write operations so that we can get rid
of the helpers here.

I think the uboot driver end up dealing with nothing but just doing some
initial parts (< 300 lines I guess), or you can take pcie_xilinx or
pci_tegra as examples.

> >         > +static void
> >         > +pcie_m32(struct mtk_pcie *pcie, u32 mask, u32 val, unsigned
> >         int reg)
> >         > +{
> >         > +     u32 v;
> >         > +
> >         > +     v = pcie_r32(pcie, reg);
> >         > +     v &= mask;
> >         > +     v |= val;
> >         > +     pcie_w32(pcie, v, reg);
> >         > +}
> >         > +
> >         > +static void
> >         > +mtk_pcie_configure_phy(struct mtk_pcie_port *port)
> >         > +{
> >         > +     int i;
> >         > +
> >         > +     for (i = 0; i < ARRAY_SIZE(mtk_phy_init); i++) {
> >         > +             void __iomem *phy_addr = (void __iomem
> >         *)port->phy_base +
> >         > +                 mtk_phy_init[i].reg;
> >         > +             u32 val = ioread32(phy_addr);
> >         > +
> >         > +             val &= ~mtk_phy_init[i].mask;
> >         > +             val |= mtk_phy_init[i].val;
> >         > +             iowrite32(val, phy_addr);
> >         > +             udelay(100);
> >         > +     }
> >         > +     mdelay(16);
> >         > +}
> >         
> >         Use PHY driver.
> >         
> >         > +static void
> >         > +mtk_pcie_configure_rc(struct mtk_pcie *pcie, struct
> >         mtk_pcie_port *port)
> >         > +{
> >         > +     ulong val = 0;
> >         > +
> >         > +     mt_pcie_write_config(NULL, (port->id) << 3,
> >         PCI_BASE_ADDRESS_0,
> >         > +                          0x80000000, PCI_SIZE_32);
> >         > +     mt_pcie_read_config(NULL, (port->id) << 3,
> >         PCI_BASE_ADDRESS_0, &val,
> >         > +                         PCI_SIZE_32);
> >         > +
> >         > +     /* Configre RC Credit */
> >         > +     val = 0;
> >         > +     mt_pcie_read_config(NULL, (port->id) << 3, 0x73c,
> >         &val, PCI_SIZE_32);
> >         > +     val &= ~(0x9fffUL) << 16;
> >         > +     val |= 0x806c << 16;
> >         > +     mt_pcie_write_config(NULL, (port->id) << 3, 0x73c,
> >         val, PCI_SIZE_32);
> >         > +     mt_pcie_read_config(NULL, (port->id) << 3, 0x73c,
> >         &val, PCI_SIZE_32);
> >         > +
> >         > +     /* Configre RC FTS number */
> >         > +     mt_pcie_read_config(NULL, (port->id) << 3, 0x70c,
> >         &val, PCI_SIZE_32);
> >         > +     val &= ~(0xff3) << 8;
> >         > +     val |= 0x50 << 8;
> >         > +     mt_pcie_write_config(NULL, (port->id) << 3, 0x70c,
> >         val, PCI_SIZE_32);
> >         > +     mt_pcie_read_config(NULL, (port->id) << 3, 0x70c,
> >         &val, PCI_SIZE_32);
> >         > +}
> >         > +
> >         > +static void
> >         > +mtk_pcie_preinit(struct mtk_pcie *pcie)
> >         > +{
> >         > +     struct mtk_pcie_port *port;
> >         > +     u32 val = 0;
> >         > +     int i;
> >         > +
> >         > +     mt7623_pcie_pinmux_set();
> >         > +
> >         > +     /* PCIe RC Reset */
> >         > +     val = 0;
> >         > +     mtk_foreach_port(port)
> >         > +             if (port->enable)
> >         > +                     val |= port->reset;
> >         > +     sys_w32(pcie, sys_r32(pcie, RSTCTL) | val, RSTCTL);
> >         > +     mdelay(12);
> >         > +     sys_w32(pcie, sys_r32(pcie, RSTCTL) & ~val, RSTCTL);
> >         > +     mdelay(12);
> >         > +
> >         > +     i = 100000;
> >         > +     while (i--) {
> >         > +             if (sys_r32(pcie, RSTSTAT) == 0)
> >         > +                     break;
> >         > +             udelay(10);
> >         > +     }
> >         
> >         We should avoid this while loop.
> >         
> >         > +     /* Configure PCIe PHY */
> >         > +
> >         > +     mtk_foreach_port(port)
> >         > +             if (port->enable)
> >         > +                     mtk_pcie_configure_phy(port);
> >         > +
> >         > +     /* PCIe EP reset */
> >         > +     val = 0;
> >         > +     mtk_foreach_port(port)
> >         > +             if (port->enable)
> >         > +                     val |= port->perst_n;
> >         > +     pcie_w32(pcie, pcie_r32(pcie, PCICFG) | val, PCICFG);
> >         > +     mdelay(12);
> >         > +     pcie_w32(pcie, pcie_r32(pcie, PCICFG) & ~val, PCICFG);
> >         > +     mdelay(200);
> >         > +
> >         > +     /* check the link status */
> >         > +     val = 0;
> >         > +     mtk_foreach_port(port) {
> >         > +             if (port->enable) {
> >         > +                     if ((pcie_r32(pcie, port->base +
> >         PCIE_SISTAT) & 0x1))
> >         > +                             port->link = 1;
> >         > +                     else
> >         > +                             val |= port->reset;
> >         > +             }
> >         > +     }
> >         > +     sys_w32(pcie, sys_r32(pcie, RSTCTL) | val, RSTCTL);
> >         > +     mdelay(200);
> >         > +
> >         > +     i = 100000;
> >         > +     while (i--) {
> >         > +             if (sys_r32(pcie, RSTSTAT) == 0)
> >         > +                     break;
> >         > +             udelay(10);
> >         > +     }
> >         > +
> >         > +     mtk_foreach_port(port) {
> >         > +             if (port->link)
> >         > +                     pcie->pcie_card_link++;
> >         > +     }
> >         > +     printf("%s: PCIe Link count=%d\n", __func__,
> >         pcie->pcie_card_link);
> >         > +     if (!pcie->pcie_card_link)
> >         > +             return;
> >         > +
> >         > +     pcie_w32(pcie, pcie->mem_bus_addr, MEMBASE);
> >         > +     pcie_w32(pcie, pcie->io_bus_addr, IOBASE);
> >         > +
> >         > +     mtk_foreach_port(port) {
> >         > +             if (port->link) {
> >         > +                     pcie_m32(pcie, 0xffffffff,
> >         port->interrupt_en, PCIENA);
> >         > +                     pcie_w32(pcie, 0x7fff0001, port->base
> >         + BAR0SETUP);
> >         > +                     pcie_w32(pcie, 0x80000000, port->base
> >         + IMBASEBAR0);
> >         > +                     pcie_w32(pcie, 0x06040001, port->base
> >         + PCIE_CLASS);
> >         magic number.
> > Descriptive by reg names.
> 
> we can directly replace these chunks with mtk_pcie_startup_port()
> (pcie-mediatek.c) and there are many defines for the registers/bit
> field.
> 
> >         
> 
> > 
> > 
> > 
> 
> 

  reply	other threads:[~2019-07-31 15:23 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-07-31 11:51 [U-Boot] [PATCH 0/4] add pcie/ahci for mt7623/bpi-r2 Frank Wunderlich
2019-07-31 11:51 ` [U-Boot] [PATCH 1/4] ahci-pci: ASM1061 report wrong class, but support AHCI Frank Wunderlich
2019-07-31 11:51 ` [U-Boot] [PATCH 2/4] ata: ahci: Don't forget to clear upper address regs Frank Wunderlich
2019-07-31 11:51 ` [U-Boot] [PATCH 3/4] pci: mediatek: Add pci-driver for mt2701 Frank Wunderlich
2019-07-31 12:45   ` Ryder Lee
2019-07-31 14:13     ` Aleksandr Rybalko
2019-07-31 14:35       ` Ryder Lee
2019-07-31 15:23         ` Ryder Lee [this message]
2019-07-31 16:09           ` Frank Wunderlich
2019-08-01  7:32             ` Ryder Lee
2019-08-04 14:35   ` Frank Wunderlich
2019-07-31 11:51 ` [U-Boot] [PATCH 4/4] arm: dts: Add PCI-E controller for mt7623 Frank Wunderlich
2019-08-04 14:53 ` [U-Boot] [PATCH 0/4] add pcie/ahci for mt7623/bpi-r2 Frank Wunderlich

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