Commit 41d9830c authored by Linus Walleij's avatar Linus Walleij
Browse files

ARM: gemini: DT for the Cortina Gemini SoC platforms 



This adds initial and compulsory device tree support to the
Gemini ARMv4 platform.

We are selecting a bunch of "absolute minimals" for getting a working
system up with just device tree:

- We select USE_OF for natural reasons or nothing works.

- We select CLKSRC_OF and GEMINI_TIMER so we get timekeeping from
  the clocksource.

- We select GPIO_GEMINI because these are used as irqchips, and
  for a generic driver it is not reasonable for those to have to
  select every possible irqchip in the world to work, the platform
  should simply provide the available irqchips.

- We select a UART that can be exprected to work with
  SERIAL_OF_PLATFORM which is the name for an 8250 OF-probed
  serial port.

- We select the syscon-based reset controller: it's not fun when
  "reboot" doesn't work because of Kconfig, so we just select
  POWER_RESET and POWER_RESET_SYSCON.

- We perhaps a bit controversiallt select ARM_APPENDED_DTB, because
  this platform is using the ancient RedBoot, and can *NOT* be
  expected to upgrade its bootloaders. Appended device tree is
  simply how these devices have to work with device tree.

Cc: Janos Laube <janos.dev@gmail.com>
Cc: Paulius Zaleckas <paulius.zaleckas@gmail.com>
Cc: Hans Ulli Kroll <ulli.kroll@googlemail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
parent c12ddfe1

arch/arm/Kconfig

+8 −2
Original line number Diff line number Diff line
@@ -361,11 +361,17 @@ config ARM_SINGLE_ARMV7M 


config ARCH_GEMINI

	bool "Cortina Systems Gemini"

	select CLKSRC_MMIO

	select ARM_APPENDED_DTB # Old Redboot bootloaders deployed

	select CPU_FA526

	select GENERIC_CLOCKEVENTS

	select FARADAY_FTINTC010

	select FTTMR010_TIMER

	select GPIO_GEMINI

	select GPIOLIB

	select MULTI_IRQ_HANDLER

	select POWER_RESET

	select POWER_RESET_SYSCON

	select SERIAL_OF_PLATFORM

	select USE_OF

	help

	  Support for the Cortina Systems Gemini family SoCs

arch/arm/mach-gemini/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -4,7 +4,7 @@ 


# Object file lists.



obj-y			:= irq.o mm.o time.o devices.o gpio.o idle.o reset.o

obj-y			:= irq.o mm.o time.o devices.o gpio.o idle.o reset.o board-dt.o



# Board-specific support

obj-$(CONFIG_MACH_NAS4220B)	+= board-nas4220b.o

arch/arm/mach-gemini/board-dt.c

0 → 100644
+38 −0
Original line number Diff line number Diff line 
/*

 * Gemini Device Tree boot support

 */

#include <linux/kernel.h>

#include <linux/init.h>

#include <linux/io.h>



#include <asm/mach/arch.h>

#include <asm/mach/map.h>



#ifdef CONFIG_DEBUG_GEMINI

/* This is needed for LL-debug/earlyprintk/debug-macro.S */

static struct map_desc gemini_io_desc[] __initdata = {

	{

		.virtual = CONFIG_DEBUG_UART_VIRT,

		.pfn = __phys_to_pfn(CONFIG_DEBUG_UART_PHYS),

		.length = SZ_4K,

		.type = MT_DEVICE,

	},

};



static void __init gemini_map_io(void)

{

	iotable_init(gemini_io_desc, ARRAY_SIZE(gemini_io_desc));

}

#else

#define gemini_map_io NULL

#endif



static const char *gemini_board_compat[] = {

	"cortina,gemini",

	NULL,

};



DT_MACHINE_START(GEMINI_DT, "Gemini (Device Tree)")

	.map_io		= gemini_map_io,

	.dt_compat	= gemini_board_compat,

MACHINE_END

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