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>

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

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.

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
 

hw/char/escc.c

@@ -31,6 +31,8 @@
 #include "qemu/module.h"
 #include "hw/char/escc.h"
 #include "ui/console.h"
+
+#include "qemu/cutils.h"
 #include "trace.h"
 
 /*
@@ -190,6 +192,7 @@
 #define R_MISC1I 14
 #define R_EXTINT 15
 
+static uint8_t sunkbd_layout_dip_switch(const char *sunkbd_layout);
 static void handle_kbd_command(ESCCChannelState *s, int val);
 static int serial_can_receive(void *opaque);
 static void serial_receive_byte(ESCCChannelState *s, int ch);
@@ -846,6 +849,79 @@ static QemuInputHandler sunkbd_handler = {
     .event = sunkbd_handle_event,
 };
 
+static uint8_t sunkbd_layout_dip_switch(const char *kbd_layout)
+{
+    /* Return the value of the dip-switches in a SUN Type 5 keyboard */
+    static uint8_t ret = 0xff;
+
+    if ((ret == 0xff) && kbd_layout) {
+        int i;
+        struct layout_values {
+            const char *lang;
+            uint8_t dip;
+        } languages[] =
+            /*
+             * Dip values from table 3-16 Layouts for Type 4, 5 and 5c Keyboards
+             */
+            {
+                {"en-us", 0x21}, /* U.S.A. (US5.kt) */
+                                 /* 0x22 is some other US (US_UNIX5.kt) */
+                {"fr",    0x23}, /* France (France5.kt) */
+                {"da",    0x24}, /* Denmark (Denmark5.kt) */
+                {"de",    0x25}, /* Germany (Germany5.kt) */
+                {"it",    0x26}, /* Italy (Italy5.kt) */
+                {"nl",    0x27}, /* The Netherlands (Netherland5.kt) */
+                {"no",    0x28}, /* Norway (Norway.kt) */
+                {"pt",    0x29}, /* Portugal (Portugal5.kt) */
+                {"es",    0x2a}, /* Spain (Spain5.kt) */
+                {"sv",    0x2b}, /* Sweden (Sweden5.kt) */
+                {"fr-ch", 0x2c}, /* Switzerland/French (Switzer_Fr5.kt) */
+                {"de-ch", 0x2d}, /* Switzerland/German (Switzer_Ge5.kt) */
+                {"en-gb", 0x2e}, /* Great Britain (UK5.kt) */
+                {"ko",    0x2f}, /* Korea (Korea5.kt) */
+                {"tw",    0x30}, /* Taiwan (Taiwan5.kt) */
+                {"ja",    0x31}, /* Japan (Japan5.kt) */
+                {"fr-ca", 0x32}, /* Canada/French (Canada_Fr5.kt) */
+                {"hu",    0x33}, /* Hungary (Hungary5.kt) */
+                {"pl",    0x34}, /* Poland (Poland5.kt) */
+                {"cz",    0x35}, /* Czech (Czech5.kt) */
+                {"ru",    0x36}, /* Russia (Russia5.kt) */
+                {"lv",    0x37}, /* Latvia (Latvia5.kt) */
+                {"tr",    0x38}, /* Turkey-Q5 (TurkeyQ5.kt) */
+                {"gr",    0x39}, /* Greece (Greece5.kt) */
+                {"ar",    0x3a}, /* Arabic (Arabic5.kt) */
+                {"lt",    0x3b}, /* Lithuania (Lithuania5.kt) */
+                {"nl-be", 0x3c}, /* Belgium (Belgian5.kt) */
+                {"be",    0x3c}, /* Belgium (Belgian5.kt) */
+            };
+
+        for (i = 0;
+             i < sizeof(languages) / sizeof(struct layout_values);
+             i++) {
+            if (!strcmp(kbd_layout, languages[i].lang)) {
+                ret = languages[i].dip;
+                return ret;
+            }
+        }
+
+        /* Found no known language code */
+        if ((kbd_layout[0] >= '0') && (kbd_layout[0] <= '9')) {
+            unsigned int tmp;
+
+            /* As a fallback we also accept numeric dip switch value */
+            if (!qemu_strtoui(kbd_layout, NULL, 0, &tmp)) {
+                ret = tmp;
+            }
+        }
+    }
+
+    if (ret == 0xff) {
+        /* Final fallback if keyboard_layout was not set or recognized */
+        ret = 0x21; /* en-us layout */
+    }
+    return ret;
+}
+
 static void handle_kbd_command(ESCCChannelState *s, int val)
 {
     trace_escc_kbd_command(val);
@@ -867,7 +943,7 @@ static void handle_kbd_command(ESCCChannelState *s, int val)
     case 0xf:
         clear_queue(s);
         put_queue(s, 0xfe);
-        put_queue(s, 0x21); /*  en-us layout */
+        put_queue(s, sunkbd_layout_dip_switch(s->sunkbd_layout));
         break;
     default:
         break;
@@ -976,6 +1052,7 @@ static Property escc_properties[] = {
     DEFINE_PROP_UINT32("chnAtype",  ESCCState, chn[1].type, 0),
     DEFINE_PROP_CHR("chrB", ESCCState, chn[0].chr),
     DEFINE_PROP_CHR("chrA", ESCCState, chn[1].chr),
+    DEFINE_PROP_STRING("chnA-sunkbd-layout", ESCCState, chn[1].sunkbd_layout),
     DEFINE_PROP_END_OF_LIST(),
 };
 

include/hw/char/escc.h

@@ -45,6 +45,7 @@ typedef struct ESCCChannelState {
     ESCCChnType type;
     uint8_t rx, tx;
     QemuInputHandlerState *hs;
+    char *sunkbd_layout;
 } ESCCChannelState;
 
 struct ESCCState {