Greg Kroah-Hartman
598cf27219
Link: https://lore.kernel.org/r/20260217200002.683975158@linuxfoundation.org Tested-by: Florian Fainelli <florian.fainelli@broadcom.com> Tested-by: Takeshi Ogasawara <takeshi.ogasawara@futuring-girl.com> Tested-by: Peter Schneider <pschneider1968@googlemail.com> Tested-by: Jon Hunter <jonathanh@nvidia.com> Tested-by: Salvatore Bonaccorso <carnil@debian.org> Tested-by: Brett A C Sheffield <bacs@librecast.net> Tested-by: Mark Brown <broonie@kernel.org> Tested-by: Luna Jernberg <droidbittin@gmail.com> Tested-by: Ronald Warsow <rwarsow@gmx.de> Tested-by: Justin M. Forbes <jforbes@fedoraproject.org> Tested-by: Ron Economos <re@w6rz.net> Tested-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
93 lines
2.1 KiB
C
93 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 <linux/iopoll.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 ret;
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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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ret = read_poll_timeout(RREG_DAC, tmp, !(tmp & 0x1),
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1000, 300000, false,
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MGA1064_SPAREREG);
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if (ret == -ETIMEDOUT)
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return;
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/*
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* 3b- This step occurs only if the remote BMC 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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(void)read_poll_timeout(RREG_DAC, tmp, (tmp & 0x2),
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1000, 300000, false,
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MGA1064_SPAREREG);
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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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