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219b45d023
Mgag200's BMC connector tracks the status of an underlying physical connector and updates the BMC status accordingly. This functionality works around GNOME's settings app, which cannot handle multiple outputs on the same CRTC. The workaround is now obsolete as the VGA-BMC connector handles BMC support internally. Hence, remove the driver's code and the BMC output entirely. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Jocelyn Falempe <jfalempe@redhat.com> Link: https://patchwork.freedesktop.org/patch/msgid/20240805130622.63458-6-tzimmermann@suse.de
99 lines
2.1 KiB
C
99 lines
2.1 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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#include <linux/delay.h>
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#include <drm/drm_atomic_helper.h>
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#include <drm/drm_edid.h>
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#include <drm/drm_managed.h>
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#include <drm/drm_probe_helper.h>
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#include "mgag200_drv.h"
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void mgag200_bmc_stop_scanout(struct mga_device *mdev)
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{
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u8 tmp;
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int iter_max;
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/*
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* 1 - The first step is to inform the BMC of an upcoming mode
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* change. We are putting the misc<0> to output.
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*/
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WREG8(DAC_INDEX, MGA1064_GEN_IO_CTL);
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tmp = RREG8(DAC_DATA);
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tmp |= 0x10;
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WREG_DAC(MGA1064_GEN_IO_CTL, tmp);
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/* we are putting a 1 on the misc<0> line */
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WREG8(DAC_INDEX, MGA1064_GEN_IO_DATA);
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tmp = RREG8(DAC_DATA);
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tmp |= 0x10;
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WREG_DAC(MGA1064_GEN_IO_DATA, tmp);
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/*
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* 2- Second step to mask any further scan request. This is
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* done by asserting the remfreqmsk bit (XSPAREREG<7>)
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*/
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WREG8(DAC_INDEX, MGA1064_SPAREREG);
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tmp = RREG8(DAC_DATA);
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tmp |= 0x80;
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WREG_DAC(MGA1064_SPAREREG, tmp);
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/*
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* 3a- The third step is to verify if there is an active scan.
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* We are waiting for a 0 on remhsyncsts <XSPAREREG<0>).
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*/
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iter_max = 300;
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while (!(tmp & 0x1) && iter_max) {
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WREG8(DAC_INDEX, MGA1064_SPAREREG);
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tmp = RREG8(DAC_DATA);
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udelay(1000);
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iter_max--;
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}
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/*
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* 3b- This step occurs only if the remove is actually
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* scanning. We are waiting for the end of the frame which is
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* a 1 on remvsyncsts (XSPAREREG<1>)
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*/
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if (iter_max) {
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iter_max = 300;
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while ((tmp & 0x2) && iter_max) {
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WREG8(DAC_INDEX, MGA1064_SPAREREG);
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tmp = RREG8(DAC_DATA);
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udelay(1000);
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iter_max--;
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}
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}
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}
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void mgag200_bmc_start_scanout(struct mga_device *mdev)
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{
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u8 tmp;
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/* Assert rstlvl2 */
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WREG8(DAC_INDEX, MGA1064_REMHEADCTL2);
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tmp = RREG8(DAC_DATA);
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tmp |= 0x8;
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WREG8(DAC_DATA, tmp);
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udelay(10);
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/* Deassert rstlvl2 */
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tmp &= ~0x08;
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WREG8(DAC_INDEX, MGA1064_REMHEADCTL2);
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WREG8(DAC_DATA, tmp);
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/* Remove mask of scan request */
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WREG8(DAC_INDEX, MGA1064_SPAREREG);
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tmp = RREG8(DAC_DATA);
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tmp &= ~0x80;
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WREG8(DAC_DATA, tmp);
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/* Put back a 0 on the misc<0> line */
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WREG8(DAC_INDEX, MGA1064_GEN_IO_DATA);
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tmp = RREG8(DAC_DATA);
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tmp &= ~0x10;
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WREG_DAC(MGA1064_GEN_IO_DATA, tmp);
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}
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