Files
cubelinux-kernel/drivers/gpu/drm/i915/display/intel_sbi.c
T
Greg Kroah-Hartman 598cf27219 Linux 6.19.3
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>
2026-02-19 16:33:27 +01:00

93 lines
2.1 KiB
C

// SPDX-License-Identifier: MIT
/*
* Copyright © 2013-2021 Intel Corporation
*
* LPT/WPT IOSF sideband.
*/
#include <drm/drm_print.h>
#include "intel_de.h"
#include "intel_display_core.h"
#include "intel_sbi.h"
#include "intel_sbi_regs.h"
/* SBI access */
static int intel_sbi_rw(struct intel_display *display, u16 reg,
enum intel_sbi_destination destination,
u32 *val, bool is_read)
{
u32 cmd;
lockdep_assert_held(&display->sbi.lock);
if (intel_de_wait_fw_ms(display, SBI_CTL_STAT,
SBI_STATUS_MASK, SBI_STATUS_READY, 100, NULL)) {
drm_err(display->drm, "timeout waiting for SBI to become ready\n");
return -EBUSY;
}
intel_de_write_fw(display, SBI_ADDR, SBI_ADDR_VALUE(reg));
intel_de_write_fw(display, SBI_DATA, is_read ? 0 : *val);
if (destination == SBI_ICLK)
cmd = SBI_CTL_DEST_ICLK | SBI_CTL_OP_CRRD;
else
cmd = SBI_CTL_DEST_MPHY | SBI_CTL_OP_IORD;
if (!is_read)
cmd |= SBI_CTL_OP_WR;
intel_de_write_fw(display, SBI_CTL_STAT, cmd | SBI_STATUS_BUSY);
if (intel_de_wait_fw_ms(display, SBI_CTL_STAT,
SBI_STATUS_MASK, SBI_STATUS_READY, 100, &cmd)) {
drm_err(display->drm, "timeout waiting for SBI to complete read\n");
return -ETIMEDOUT;
}
if (cmd & SBI_RESPONSE_FAIL) {
drm_err(display->drm, "error during SBI read of reg %x\n", reg);
return -ENXIO;
}
if (is_read)
*val = intel_de_read_fw(display, SBI_DATA);
return 0;
}
void intel_sbi_lock(struct intel_display *display)
{
mutex_lock(&display->sbi.lock);
}
void intel_sbi_unlock(struct intel_display *display)
{
mutex_unlock(&display->sbi.lock);
}
u32 intel_sbi_read(struct intel_display *display, u16 reg,
enum intel_sbi_destination destination)
{
u32 result = 0;
intel_sbi_rw(display, reg, destination, &result, true);
return result;
}
void intel_sbi_write(struct intel_display *display, u16 reg, u32 value,
enum intel_sbi_destination destination)
{
intel_sbi_rw(display, reg, destination, &value, false);
}
void intel_sbi_init(struct intel_display *display)
{
mutex_init(&display->sbi.lock);
}
void intel_sbi_fini(struct intel_display *display)
{
mutex_destroy(&display->sbi.lock);
}