escc: emulate dip switch language layout settings on SUN keyboard

SUN Type 4, 5 and 5c keyboards have dip switches to choose the language layout
of the keyboard. Solaris makes an ioctl to query the value of the dipswitches
and uses that value to select keyboard layout.  Also the SUN bios like the one
in the file ss5.bin uses this value to support at least some keyboard layouts.
However, the OpenBIOS provided with qemu is hardcoded to always use an US
keyboard layout.

Before this patch, qemu allways gave dip switch value 0x21 (US keyboard),
this patch uses a command line switch like
"-global escc.chnA-sunkbd-layout=de" to select dip switch value. A table is
used to lookup values from arguments like:

-global escc.chnA-sunkbd-layout=fr
-global escc.chnA-sunkbd-layout=es

But the patch also accepts numeric dip switch values directly:

-global escc.chnA-sunkbd-layout=0x2b
-global escc.chnA-sunkbd-layout=43

Both values above are the same and select swedish keyboard as explained in
table 3-15 at
https://docs.oracle.com/cd/E19683-01/806-6642/new-43/index.html

Unless you want to do a full Solaris installation but happen to have
access to a Sun bios file, the easiest way to test that the patch works
is to:

qemu-system-sparc -global escc.chnA-sunkbd-layout=sv -bios /path/to/ss5.bin

If you already happen to have a Solaris installation in a qemu disk image
file you can easily try different keyboard layouts after this patch is
applied.

Signed-off-by: Henrik Carlqvist <hc1245@poolhem.se>
Message-Id: <20230623203007.56d3d182.hc981@poolhem.se>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
[MCA edit: update unsigned char to uint8_t, fix spacing issues]
Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>

3 files changed, 131 insertions, 1 deletions

diff --git a/docs/system/device-emulation.rst b/docs/system/device-emulation.rst
index 8d4a182..4491c4c 100644
--- a/docs/system/device-emulation.rst
+++ b/docs/system/device-emulation.rst
@@ -86,6 +86,7 @@ Emulated Devices
    devices/ccid.rst
    devices/cxl.rst
    devices/ivshmem.rst
+   devices/keyboard.rst
    devices/net.rst
    devices/nvme.rst
    devices/usb.rst
diff --git a/docs/system/devices/keyboard.rst b/docs/system/devices/keyboard.rst
new file mode 100644
index 0000000..a8f9fbe
--- /dev/null
+++ b/docs/system/devices/keyboard.rst
@@ -0,0 +1,129 @@
+.. _keyboard:
+
+Sparc32 keyboard
+----------------
+SUN Type 4, 5 and 5c keyboards have dip switches to choose the language layout
+of the keyboard. Solaris makes an ioctl to query the value of the dipswitches
+and uses that value to select keyboard layout. Also the SUN bios like the one
+in the file ss5.bin uses this value to support at least some keyboard layouts.
+However, the OpenBIOS provided with qemu is hardcoded to always use an
+US keyboard layout.
+
+With the escc.chnA-sunkbd-layout driver property it is possible to select
+keyboard layout. Example:
+
+-global escc.chnA-sunkbd-layout=de
+
+Depending on type of keyboard, the keyboard can have 6 or 5 dip-switches to
+select keyboard layout, giving up to 64 different layouts. Not all
+combinations are supported by Solaris and even less by Sun OpenBoot BIOS.
+
+The dip switch settings can be given as hexadecimal number, decimal number
+or in some cases as a language string. Examples:
+
+-global escc.chnA-sunkbd-layout=0x2b
+
+-global escc.chnA-sunkbd-layout=43
+
+-global escc.chnA-sunkbd-layout=sv
+
+The above 3 examples all select a swedish keyboard layout. Table 3-15 at
+https://docs.oracle.com/cd/E19683-01/806-6642/new-43/index.html explains which
+keytable file is used for different dip switch settings. The information
+in that table can be summarized in this table:
+
+.. list-table:: Language selection values for escc.chnA-sunkbd-layout
+   :widths: 10 10 10
+   :header-rows: 1
+
+   * - Hexadecimal value
+     - Decimal value
+     - Language code
+   * - 0x21
+     - 33
+     - en-us
+   * - 0x23
+     - 35
+     - fr
+   * - 0x24
+     - 36
+     - da
+   * - 0x25
+     - 37
+     - de
+   * - 0x26
+     - 38
+     - it
+   * - 0x27
+     - 39
+     - nl
+   * - 0x28
+     - 40
+     - no
+   * - 0x29
+     - 41
+     - pt
+   * - 0x2a
+     - 42
+     - es
+   * - 0x2b
+     - 43
+     - sv
+   * - 0x2c
+     - 44
+     - fr-ch
+   * - 0x2d
+     - 45
+     - de-ch
+   * - 0x2e
+     - 46
+     - en-gb
+   * - 0x2f
+     - 47
+     - ko
+   * - 0x30
+     - 48
+     - tw
+   * - 0x31
+     - 49
+     - ja
+   * - 0x32
+     - 50
+     - fr-ca
+   * - 0x33
+     - 51
+     - hu
+   * - 0x34
+     - 52
+     - pl
+   * - 0x35
+     - 53
+     - cz
+   * - 0x36
+     - 54
+     - ru
+   * - 0x37
+     - 55
+     - lv
+   * - 0x38
+     - 56
+     - tr
+   * - 0x39
+     - 57
+     - gr
+   * - 0x3a
+     - 58
+     - ar
+   * - 0x3b
+     - 59
+     - lt
+   * - 0x3c
+     - 60
+     - nl-be
+   * - 0x3c
+     - 60
+     - be
+
+Not all dip switch values have a corresponding language code and both "be" and
+"nl-be" correspond to the same dip switch value. By default, if no value is
+given to escc.chnA-sunkbd-layout 0x21 (en-us) will be used.
diff --git a/docs/system/target-sparc.rst b/docs/system/target-sparc.rst
index b55f8d0..9ec8c90 100644
--- a/docs/system/target-sparc.rst
+++ b/docs/system/target-sparc.rst
@@ -38,7 +38,7 @@ QEMU emulates the following sun4m peripherals:
 -  Non Volatile RAM M48T02/M48T08
 
 -  Slave I/O: timers, interrupt controllers, Zilog serial ports,
-   keyboard and power/reset logic
+   :ref:`keyboard` and power/reset logic
 
 -  ESP SCSI controller with hard disk and CD-ROM support