Commit 715eb05b authored by Gerd Hoffmann's avatar Gerd Hoffmann
Browse files

i2c: switch ddc to use the new edid generator 



This also makes the default display resolution configurable,
via xres and yres properties.  The default is 1024x768.

The old code had a hard-coded resolution of 1600x1200.

Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: BALATON Zoltan <balaton@eik.bme.hu>
Signed-off-by: default avatarGerd Hoffmann <kraxel@redhat.com>
Message-id: 20181005110837.28209-1-kraxel@redhat.com
parent 2f99f80c

hw/i2c/i2c-ddc.c

+8 −192
Original line number Diff line number Diff line
@@ -32,197 +32,6 @@ 
    }                                                                          \

} while (0)



/* Structure defining a monitor's characteristics in a

 * readable format: this should be passed to build_edid_blob()

 * to convert it into the 128 byte binary EDID blob.

 * Not all bits of the EDID are customisable here.

 */

struct EDIDData {

    char manuf_id[3]; /* three upper case letters */

    uint16_t product_id;

    uint32_t serial_no;

    uint8_t manuf_week;

    int manuf_year;

    uint8_t h_cm;

    uint8_t v_cm;

    uint8_t gamma;

    char monitor_name[14];

    char serial_no_string[14];

    /* Range limits */

    uint8_t vmin; /* Hz */

    uint8_t vmax; /* Hz */

    uint8_t hmin; /* kHz */

    uint8_t hmax; /* kHz */

    uint8_t pixclock; /* MHz / 10 */

    uint8_t timing_data[18];

};



typedef struct EDIDData EDIDData;



/* EDID data for a simple LCD monitor */

static const EDIDData lcd_edid = {

    /* The manuf_id ought really to be an assigned EISA ID */

    .manuf_id = "QMU",

    .product_id = 0,

    .serial_no = 1,

    .manuf_week = 1,

    .manuf_year = 2011,

    .h_cm = 40,

    .v_cm = 30,

    .gamma = 0x78,

    .monitor_name = "QEMU monitor",

    .serial_no_string = "1",

    .vmin = 40,

    .vmax = 120,

    .hmin = 30,

    .hmax = 100,

    .pixclock = 18,

    .timing_data = {

        /* Borrowed from a 21" LCD */

        0x48, 0x3f, 0x40, 0x30, 0x62, 0xb0, 0x32, 0x40, 0x40,

        0xc0, 0x13, 0x00, 0x98, 0x32, 0x11, 0x00, 0x00, 0x1e

    }

};



static uint8_t manuf_char_to_int(char c)

{

    return (c - 'A') & 0x1f;

}



static void write_ascii_descriptor_block(uint8_t *descblob, uint8_t blocktype,

                                         const char *string)

{

    /* Write an EDID Descriptor Block of the "ascii string" type */

    int i;

    descblob[0] = descblob[1] = descblob[2] = descblob[4] = 0;

    descblob[3] = blocktype;

    /* The rest is 13 bytes of ASCII; if less then the rest must

     * be filled with newline then spaces

     */

    for (i = 5; i < 19; i++) {

        descblob[i] = string[i - 5];

        if (!descblob[i]) {

            break;

        }

    }

    if (i < 19) {

        descblob[i++] = '\n';

    }

    for ( ; i < 19; i++) {

        descblob[i] = ' ';

    }

}



static void write_range_limits_descriptor(const EDIDData *edid,

                                          uint8_t *descblob)

{

    int i;

    descblob[0] = descblob[1] = descblob[2] = descblob[4] = 0;

    descblob[3] = 0xfd;

    descblob[5] = edid->vmin;

    descblob[6] = edid->vmax;

    descblob[7] = edid->hmin;

    descblob[8] = edid->hmax;

    descblob[9] = edid->pixclock;

    descblob[10] = 0;

    descblob[11] = 0xa;

    for (i = 12; i < 19; i++) {

        descblob[i] = 0x20;

    }

}



static void build_edid_blob(const EDIDData *edid, uint8_t *blob)

{

    /* Write an EDID 1.3 format blob (128 bytes) based

     * on the EDIDData structure.

     */

    int i;

    uint8_t cksum;



    /* 00-07 : header */

    blob[0] = blob[7] = 0;

    for (i = 1 ; i < 7; i++) {

        blob[i] = 0xff;

    }

    /* 08-09 : manufacturer ID */

    blob[8] = (manuf_char_to_int(edid->manuf_id[0]) << 2)

        | (manuf_char_to_int(edid->manuf_id[1]) >> 3);

    blob[9] = (manuf_char_to_int(edid->manuf_id[1]) << 5)

        | manuf_char_to_int(edid->manuf_id[2]);

    /* 10-11 : product ID code */

    blob[10] = edid->product_id;

    blob[11] = edid->product_id >> 8;

    blob[12] = edid->serial_no;

    blob[13] = edid->serial_no >> 8;

    blob[14] = edid->serial_no >> 16;

    blob[15] = edid->serial_no >> 24;

    /* 16 : week of manufacture */

    blob[16] = edid->manuf_week;

    /* 17 : year of manufacture - 1990 */

    blob[17] = edid->manuf_year - 1990;

    /* 18, 19 : EDID version and revision */

    blob[18] = 1;

    blob[19] = 3;

    /* 20 - 24 : basic display parameters */

    /* We are always a digital display */

    blob[20] = 0x80;

    /* 21, 22 : max h/v size in cm */

    blob[21] = edid->h_cm;

    blob[22] = edid->v_cm;

    /* 23 : gamma (divide by 100 then add 1 for actual value) */

    blob[23] = edid->gamma;

    /* 24 feature support: no power management, RGB, preferred timing mode,

     * standard colour space

     */

    blob[24] = 0x0e;

    /* 25 - 34 : chromaticity coordinates. These are the

     * standard sRGB chromaticity values

     */

    blob[25] = 0xee;

    blob[26] = 0x91;

    blob[27] = 0xa3;

    blob[28] = 0x54;

    blob[29] = 0x4c;

    blob[30] = 0x99;

    blob[31] = 0x26;

    blob[32] = 0x0f;

    blob[33] = 0x50;

    blob[34] = 0x54;

    /* 35, 36 : Established timings: claim to support everything */

    blob[35] = blob[36] = 0xff;

    /* 37 : manufacturer's reserved timing: none */

    blob[37] = 0;

    /* 38 - 53 : standard timing identification

     * don't claim anything beyond what the 'established timings'

     * already provide. Unused slots must be (0x1, 0x1)

     */

    for (i = 38; i < 54; i++) {

        blob[i] = 0x1;

    }

    /* 54 - 71 : descriptor block 1 : must be preferred timing data */

    memcpy(blob + 54, edid->timing_data, 18);

    /* 72 - 89, 90 - 107, 108 - 125 : descriptor block 2, 3, 4

     * Order not important, but we must have a monitor name and a

     * range limits descriptor.

     */

    write_range_limits_descriptor(edid, blob + 72);

    write_ascii_descriptor_block(blob + 90, 0xfc, edid->monitor_name);

    write_ascii_descriptor_block(blob + 108, 0xff, edid->serial_no_string);



    /* 126 : extension flag */

    blob[126] = 0;



    cksum = 0;

    for (i = 0; i < 127; i++) {

        cksum += blob[i];

    }

    /* 127 : checksum */

    blob[127] = -cksum;

    if (DEBUG_I2CDDC) {

        qemu_hexdump((char *)blob, stdout, "", 128);

    }

}



static void i2c_ddc_reset(DeviceState *ds)

{

    I2CDDCState *s = I2CDDC(ds);
@@ -270,7 +79,8 @@ static int i2c_ddc_tx(I2CSlave *i2c, uint8_t data) 
static void i2c_ddc_init(Object *obj)

{

    I2CDDCState *s = I2CDDC(obj);

    build_edid_blob(&lcd_edid, s->edid_blob);



    qemu_edid_generate(s->edid_blob, sizeof(s->edid_blob), &s->edid_info);

}



static const VMStateDescription vmstate_i2c_ddc = {
@@ -283,6 +93,11 @@ static const VMStateDescription vmstate_i2c_ddc = { 
    }

};



static Property i2c_ddc_properties[] = {

    DEFINE_EDID_PROPERTIES(I2CDDCState, edid_info),

    DEFINE_PROP_END_OF_LIST(),

};



static void i2c_ddc_class_init(ObjectClass *oc, void *data)

{

    DeviceClass *dc = DEVICE_CLASS(oc);
@@ -290,6 +105,7 @@ static void i2c_ddc_class_init(ObjectClass *oc, void *data) 


    dc->reset = i2c_ddc_reset;

    dc->vmsd = &vmstate_i2c_ddc;

    dc->props = i2c_ddc_properties;

    isc->event = i2c_ddc_event;

    isc->recv = i2c_ddc_rx;

    isc->send = i2c_ddc_tx;

include/hw/i2c/i2c-ddc.h

+3 −1
Original line number Diff line number Diff line
@@ -19,14 +19,16 @@ 
#ifndef I2C_DDC_H

#define I2C_DDC_H



/* A simple I2C slave which just returns the contents of its EDID blob. */

#include "hw/display/edid.h"



/* A simple I2C slave which just returns the contents of its EDID blob. */

struct I2CDDCState {

    /*< private >*/

    I2CSlave i2c;

    /*< public >*/

    bool firstbyte;

    uint8_t reg;

    qemu_edid_info edid_info;

    uint8_t edid_blob[128];

};