docs/system/arm: Document the various raspi boards

Document the following Raspberry Pi models:

 - raspi0               Raspberry Pi Zero (revision 1.2)
 - raspi1ap             Raspberry Pi A+ (revision 1.1)
 - raspi2b              Raspberry Pi 2B (revision 1.1)
 - raspi3ap             Raspberry Pi 3A+ (revision 1.0)
 - raspi3b              Raspberry Pi 3B (revision 1.2)

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-id: 20201120173953.2539469-3-f4bug@amsat.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

MAINTAINERS

@@ -803,6 +803,7 @@ F: hw/arm/raspi_platform.h
 F: hw/*/bcm283*
 F: include/hw/arm/raspi*
 F: include/hw/*/bcm283*
+F: docs/system/arm/raspi.rst
 
 Real View
 M: Peter Maydell <peter.maydell@linaro.org>

docs/system/arm/raspi.rst

@@ -0,0 +1,43 @@
+Raspberry Pi boards (``raspi0``, ``raspi1ap``, ``raspi2b``, ``raspi3ap``, ``raspi3b``)
+======================================================================================
+
+
+QEMU provides models of the following Raspberry Pi boards:
+
+``raspi0`` and ``raspi1ap``
+  ARM1176JZF-S core, 512 MiB of RAM
+``raspi2b``
+  Cortex-A7 (4 cores), 1 GiB of RAM
+``raspi3ap``
+  Cortex-A53 (4 cores), 512 MiB of RAM
+``raspi3b``
+  Cortex-A53 (4 cores), 1 GiB of RAM
+
+
+Implemented devices
+-------------------
+
+ * ARM1176JZF-S, Cortex-A7 or Cortex-A53 CPU
+ * Interrupt controller
+ * DMA controller
+ * Clock and reset controller (CPRMAN)
+ * System Timer
+ * GPIO controller
+ * Serial ports (BCM2835 AUX - 16550 based - and PL011)
+ * Random Number Generator (RNG)
+ * Frame Buffer
+ * USB host (USBH)
+ * GPIO controller
+ * SD/MMC host controller
+ * SoC thermal sensor
+ * USB2 host controller (DWC2 and MPHI)
+ * MailBox controller (MBOX)
+ * VideoCore firmware (property)
+
+
+Missing devices
+---------------
+
+ * Peripheral SPI controller (SPI)
+ * Analog to Digital Converter (ADC)
+ * Pulse Width Modulation (PWM)

docs/system/target-arm.rst

@@ -90,6 +90,7 @@ undocumented; you can get a complete list by running
    arm/nuvoton
    arm/orangepi
    arm/palm
+   arm/raspi
    arm/xscale
    arm/collie
    arm/sx1