MIPS: ranchu: Add Ranchu as a new generic-based board

Provide amendments to the MIPS generic platform framework so that
the new generic-based board Ranchu can be chosen to be built.

The Ranchu board is intended to be used by Android emulator. The name
"Ranchu" originates from Android development community. "Goldfish" and
"Ranchu" are terms used for two generations of virtual boards used by
Android emulator. The name "Ranchu" is a newer one among the two, and
this patch deals with Ranchu. However, for historical reasons, some
devices/drivers still contain the name "Goldfish".

MIPS Ranchu machine includes a number of Goldfish devices. The support
for Virtio devices is also included. Ranchu board supports up to 16
Virtio devices which can be attached using Virtio MMIO Bus. This is
summarized in the following picture:

       ABUS
        ||----MIPS CPU
        ||       |                    IRQs
        ||----Goldfish PIC------------(32)--------
        ||                     | | | | | | | | |
        ||----Goldfish TTY------ | | | | | | | |
        ||                       | | | | | | | |
        ||----Goldfish RTC-------- | | | | | | |
        ||                         | | | | | | |
        ||----Goldfish FB----------- | | | | | |
        ||                           | | | | | |
        ||----Goldfish Events--------- | | | | |
        ||                             | | | | |
        ||----Goldfish Audio------------ | | | |
        ||                               | | | |
        ||----Goldfish Battery------------ | | |
        ||                                 | | |
        ||----Android PIPE------------------ | |
        ||                                   | |
        ||----Virtio MMIO Bus                | |
        ||    |    |    |                    | |
        ||    |    |   (virtio-block)--------- |
        ||   (16)  |                           |
        ||    |   (virtio-net)------------------

Device Tree is created on the QEMU side based on the information about
devices IO map and IRQ numbers. Kernel will load this DTB using UHI
boot protocol DTB handover mode.

Signed-off-by: Miodrag Dinic <miodrag.dinic@mips.com>
Signed-off-by: Goran Ferenc <goran.ferenc@mips.com>
Signed-off-by: Aleksandar Markovic <aleksandar.markovic@mips.com>
Reviewed-by: James Hogan <jhogan@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/18138/
Signed-off-by: James Hogan <jhogan@kernel.org>

diff --git a/MAINTAINERS b/MAINTAINERS
index 5ce468fe20886f140fe5acab0014c87a81840857..0e7561d6c2d779e0898cb7993fe2cfb89bccf7a3 100644 (file)
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -11456,6 +11456,13 @@ S:     Maintained
 F:     Documentation/blockdev/ramdisk.txt
 F:     drivers/block/brd.c
 
+RANCHU VIRTUAL BOARD FOR MIPS
+M:     Miodrag Dinic <miodrag.dinic@mips.com>
+L:     linux-mips@linux-mips.org
+S:     Supported
+F:     arch/mips/generic/board-ranchu.c
+F:     arch/mips/configs/generic/board-ranchu.config
+
 RANDOM NUMBER DRIVER
 M:     "Theodore Ts'o" <tytso@mit.edu>
 S:     Maintained

diff --git a/arch/mips/configs/generic/board-ranchu.config b/arch/mips/configs/generic/board-ranchu.config
new file mode 100644 (file)
index 0000000..fee9ad4
--- /dev/null
+++ b/arch/mips/configs/generic/board-ranchu.config
@@ -0,0 +1,30 @@
+CONFIG_VIRT_BOARD_RANCHU=y
+
+CONFIG_BATTERY_GOLDFISH=y
+CONFIG_FB=y
+CONFIG_FB_GOLDFISH=y
+CONFIG_GOLDFISH=y
+CONFIG_STAGING=y
+CONFIG_GOLDFISH_AUDIO=y
+CONFIG_GOLDFISH_PIC=y
+CONFIG_GOLDFISH_PIPE=y
+CONFIG_GOLDFISH_TTY=y
+CONFIG_RTC_CLASS=y
+CONFIG_RTC_DRV_GOLDFISH=y
+
+CONFIG_INPUT_EVDEV=y
+CONFIG_INPUT_KEYBOARD=y
+CONFIG_KEYBOARD_GOLDFISH_EVENTS=y
+
+CONFIG_MAGIC_SYSRQ=y
+CONFIG_POWER_SUPPLY=y
+CONFIG_POWER_RESET=y
+CONFIG_POWER_RESET_SYSCON=y
+CONFIG_POWER_RESET_SYSCON_POWEROFF=y
+
+CONFIG_VIRTIO_BLK=y
+CONFIG_VIRTIO_CONSOLE=y
+CONFIG_VIRTIO_MMIO=y
+CONFIG_VIRTIO_MMIO_CMDLINE_DEVICES=y
+CONFIG_NETDEVICES=y
+CONFIG_VIRTIO_NET=y

diff --git a/arch/mips/generic/Kconfig b/arch/mips/generic/Kconfig
index 52e0286a161203d5904089c301bb2120a28cd77d..2ff3b17bfab18d829d74a1cb8c0e3fb790789d1b 100644 (file)
--- a/arch/mips/generic/Kconfig
+++ b/arch/mips/generic/Kconfig
@@ -49,4 +49,14 @@ config FIT_IMAGE_FDT_XILFPGA
          Enable this to include the FDT for the MIPSfpga platform
          from Imagination Technologies in the FIT kernel image.
 
+config VIRT_BOARD_RANCHU
+       bool "Support Ranchu platform for Android emulator"
+       help
+         This enables support for the platform used by Android emulator.
+
+         Ranchu platform consists of a set of virtual devices. This platform
+         enables emulation of variety of virtual configurations while using
+         Android emulator. Android emulator is based on Qemu, and contains
+         the support for the same set of virtual devices.
+
 endif

diff --git a/arch/mips/generic/Makefile b/arch/mips/generic/Makefile
index 874967363dbb20a0c61d6f21b3cbc4d211c7a77d..5fb60c86537b8edeaf5210289ea26eb324e55aa5 100644 (file)
--- a/arch/mips/generic/Makefile
+++ b/arch/mips/generic/Makefile
@@ -15,3 +15,4 @@ obj-y += proc.o
 obj-$(CONFIG_YAMON_DT_SHIM)            += yamon-dt.o
 obj-$(CONFIG_LEGACY_BOARD_SEAD3)       += board-sead3.o
 obj-$(CONFIG_KEXEC)                    += kexec.o
+obj-$(CONFIG_VIRT_BOARD_RANCHU)        += board-ranchu.o

diff --git a/arch/mips/generic/board-ranchu.c b/arch/mips/generic/board-ranchu.c
new file mode 100644 (file)
index 0000000..ea451b8
--- /dev/null
+++ b/arch/mips/generic/board-ranchu.c
@@ -0,0 +1,92 @@
+/*
+ * Support code for virtual Ranchu board for MIPS.
+ *
+ * Author: Miodrag Dinic <miodrag.dinic@mips.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/of_address.h>
+#include <linux/types.h>
+
+#include <asm/machine.h>
+#include <asm/mipsregs.h>
+#include <asm/time.h>
+
+#define GOLDFISH_TIMER_LOW             0x00
+#define GOLDFISH_TIMER_HIGH            0x04
+
+static __init u64 read_rtc_time(void __iomem *base)
+{
+       u32 time_low;
+       u32 time_high;
+
+       /*
+        * Reading the low address latches the high value
+        * as well so there is no fear that we may read
+        * inaccurate high value.
+        */
+       time_low = readl(base + GOLDFISH_TIMER_LOW);
+       time_high = readl(base + GOLDFISH_TIMER_HIGH);
+
+       return ((u64)time_high << 32) | time_low;
+}
+
+static __init unsigned int ranchu_measure_hpt_freq(void)
+{
+       u64 rtc_start, rtc_current, rtc_delta;
+       unsigned int start, count;
+       struct device_node *np;
+       void __iomem *rtc_base;
+
+       np = of_find_compatible_node(NULL, NULL, "google,goldfish-rtc");
+       if (!np)
+               panic("%s(): Failed to find 'google,goldfish-rtc' dt node!",
+                     __func__);
+
+       rtc_base = of_iomap(np, 0);
+       if (!rtc_base)
+               panic("%s(): Failed to ioremap Goldfish RTC base!", __func__);
+
+       /*
+        * Poll the nanosecond resolution RTC for one
+        * second to calibrate the CPU frequency.
+        */
+       rtc_start = read_rtc_time(rtc_base);
+       start = read_c0_count();
+
+       do {
+               rtc_current = read_rtc_time(rtc_base);
+               rtc_delta = rtc_current - rtc_start;
+       } while (rtc_delta < NSEC_PER_SEC);
+
+       count = read_c0_count() - start;
+
+       /*
+        * Make sure the frequency will be a round number.
+        * Without this correction, the returned value may vary
+        * between subsequent emulation executions.
+        *
+        * TODO: Set this value using device tree.
+        */
+       count += 5000;
+       count -= count % 10000;
+
+       iounmap(rtc_base);
+
+       return count;
+}
+
+static const struct of_device_id ranchu_of_match[] __initconst = {
+       {
+               .compatible = "mti,ranchu",
+       },
+};
+
+MIPS_MACHINE(ranchu) = {
+       .matches = ranchu_of_match,
+       .measure_hpt_freq = ranchu_measure_hpt_freq,
+};