[U-Boot] [PATCH v2 4/8] x86: slimbootloader: Add serial driver
Park, Aiden
aiden.park at intel.com
Mon Jul 8 16:37:00 UTC 2019
Hi Bin,
> -----Original Message-----
> From: Bin Meng [mailto:bmeng.cn at gmail.com]
> Sent: Tuesday, July 2, 2019 7:14 AM
> To: Park, Aiden <aiden.park at intel.com>
> Cc: U-Boot Mailing List <u-boot at lists.denx.de>; Simon Glass
> <sjg at chromium.org>
> Subject: Re: [PATCH v2 4/8] x86: slimbootloader: Add serial driver
>
> Hi Aiden,
>
> On Wed, Jun 26, 2019 at 7:19 AM Park, Aiden <aiden.park at intel.com> wrote:
> >
> > - Get serial port information from the serial port info hob
>
> Again, the same question: does this serial port info hob apply to FSP based
> board? (eg: newer FSP produces such hob for bootloader to use?) If yes, we
> probably need rename the driver to something more generic, like "intel,hob-
> uart"?
These HOB is provided from Slim Bootloader, not from FSP. Slim Bootloader consumes FSP HOB, but it's removed before loading a Payload. Instead of FSP HOB, Slim Bootloader generates some new HOBs for Payload usages only. This serial port info hob also is only generated from Slim Bootloader. Let me add a brief description in next patch.
>
>
> > - Leverage ns16550 driver with slimbootloader specific platform data
> >
> > Signed-off-by: Aiden Park <aiden.park at intel.com>
> > ---
> > arch/x86/cpu/slimbootloader/Makefile | 2 +-
> > arch/x86/cpu/slimbootloader/serial.c | 62 +++++++++++++++++++
> > .../asm/arch-slimbootloader/slimbootloader.h | 33 ++++++++++
> > 3 files changed, 96 insertions(+), 1 deletion(-) create mode 100644
> > arch/x86/cpu/slimbootloader/serial.c
> >
> > diff --git a/arch/x86/cpu/slimbootloader/Makefile
> > b/arch/x86/cpu/slimbootloader/Makefile
> > index 4b0b3e71c9..3e62f564cd 100644
> > --- a/arch/x86/cpu/slimbootloader/Makefile
> > +++ b/arch/x86/cpu/slimbootloader/Makefile
> > @@ -2,4 +2,4 @@
> > #
> > # Copyright (C) 2019 Intel Corporation <www.intel.com>
> >
> > -obj-y += car.o slimbootloader.o hob.o dram.o
> > +obj-y += car.o slimbootloader.o hob.o dram.o serial.o
> > diff --git a/arch/x86/cpu/slimbootloader/serial.c
> > b/arch/x86/cpu/slimbootloader/serial.c
> > new file mode 100644
> > index 0000000000..186c7a79ef
> > --- /dev/null
> > +++ b/arch/x86/cpu/slimbootloader/serial.c
> > @@ -0,0 +1,62 @@
> > +// SPDX-License-Identifier: GPL-2.0+
> > +/*
> > + * Copyright (C) 2019 Intel Corporation <www.intel.com> */
> > +
> > +#include <common.h>
> > +#include <dm.h>
> > +#include <ns16550.h>
> > +#include <serial.h>
> > +#include <asm/arch/slimbootloader.h>
> > +
> > +int slimbootloader_serial_ofdata_to_platdata(struct udevice *dev) {
> > + const struct efi_guid guid = LOADER_SERIAL_PORT_INFO_GUID;
> > + struct serial_port_info *serial_info = NULL;
> > + struct ns16550_platdata *plat = dev->platdata;
> > +
> > + serial_info = (struct serial_port_info *)
> > + get_next_guid_hob_data(&guid, gd->arch.hob_list);
> > +
> > + if (!serial_info) {
> > + debug("failed to get serial port information\n");
> > + return -ENOENT;
> > + }
> > + debug("type:%d base=0x%08x baudrate=%d stride=%d clk=%d\n",
> > + serial_info->type,
> > + serial_info->base,
> > + serial_info->baud,
> > + serial_info->stride,
> > + serial_info->clk);
> > +
> > + /*
> > + * The serial_info->type provides port io or mmio access type info,
> > + * but the access type will be controlled by
> > + * CONFIG_SYS_NS16550_PORT_MAPPED or
> CONFIG_SYS_NS16550_MEM32.
> > + *
> > + * TBD: ns16550 access type configuration in runtime.
> > + * ex) plat->access_type = serial_info->type
> > + */
> > + plat->base = serial_info->base;
> > + /* ns16550 uses reg_shift, then covert stride to shift */
> > + plat->reg_shift = (serial_info->stride >> 1);
> > + plat->clock = serial_info->clk;
> > +
> > + return 0;
> > +}
> > +
> > +static const struct udevice_id slimbootloader_serial_ids[] = {
> > + { .compatible = "intel,slimbootloader-uart" },
> > + {}
> > +};
> > +
> > +U_BOOT_DRIVER(serial_slimbootloader) = {
> > + .name = "serial_slimbootloader",
> > + .id = UCLASS_SERIAL,
> > + .of_match = slimbootloader_serial_ids,
> > + .ofdata_to_platdata = slimbootloader_serial_ofdata_to_platdata,
> > + .platdata_auto_alloc_size = sizeof(struct ns16550_platdata),
> > + .priv_auto_alloc_size = sizeof(struct NS16550),
> > + .probe = ns16550_serial_probe,
> > + .ops = &ns16550_serial_ops,
> > +};
> > diff --git a/arch/x86/include/asm/arch-slimbootloader/slimbootloader.h
> > b/arch/x86/include/asm/arch-slimbootloader/slimbootloader.h
> > index c85201e711..b05e527148 100644
> > --- a/arch/x86/include/asm/arch-slimbootloader/slimbootloader.h
> > +++ b/arch/x86/include/asm/arch-slimbootloader/slimbootloader.h
> > @@ -16,6 +16,12 @@
> > { 0xa9, 0xe4, 0x92, 0xf3, 0x57, 0xd1, 0x28, 0x32 } \
> > }
> >
> > +#define LOADER_SERIAL_PORT_INFO_GUID \
> > + { \
> > + 0x6c6872fe, 0x56a9, 0x4403, \
> > + { 0xbb, 0x98, 0x95, 0x8d, 0x62, 0xde, 0x87, 0xf1 } \
> > + }
> > +
> > /**
> > * A single entry of memory map information
> > *
> > @@ -48,6 +54,33 @@ struct memory_map_info {
> > struct memory_map_entry entry[0]; } __packed;
> >
> > +/**
> > + * This includes serial port info which has already been initialized
> > +in previous
> > + * Slim Bootloader stage.
> > + * The Slim Bootloader initializes serial port regardless of
> > +debug/release build
> > + * modes, and it passes the information to a payload thru hob. So, a
> > +payload can
> > + * re-use the serial information without re-initializing serial port.
> > + *
> > + * @rev : revision of serial_port_info structure. currently 1.
> > + * @rsvd : padding for alignment
> > + * @type : port io: 1, mmio: 2
> > + * @base : io base address. ex) 0x3f8, 0x80001000
> > + * @baud : uart baud rate
> > + * @stride: register stride in Bytes
> > + * @clk : uart frequency in Hz
> > + * @rsvd1 : reserved
> > + */
> > +struct serial_port_info {
> > + u8 rev;
> > + u8 rsvd[3];
> > + u32 type;
> > + u32 base;
> > + u32 baud;
> > + u32 stride;
> > + u32 clk;
> > + u32 rsvd1;
> > +} __packed;
> > +
> > /**
> > * This returns a pointer to hob data buffer if the given guid hob is found.
> > *
> > --
> > 2.20.1
> >
Best Regards,
Aiden
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