blob: 713cfba71475c9cb4c757e6a38c5e1ee1a76ef5d [file] [log] [blame]
// SPDX-License-Identifier: MIT
/*
* Copyright © 2021 Intel Corporation
*/
#include "i915_reg.h"
#include "intel_de.h"
#include "intel_display_types.h"
#include "intel_panel.h"
#include "intel_pch_refclk.h"
#include "intel_sbi.h"
static void lpt_fdi_reset_mphy(struct drm_i915_private *dev_priv)
{
intel_de_rmw(dev_priv, SOUTH_CHICKEN2, 0, FDI_MPHY_IOSFSB_RESET_CTL);
if (wait_for_us(intel_de_read(dev_priv, SOUTH_CHICKEN2) &
FDI_MPHY_IOSFSB_RESET_STATUS, 100))
drm_err(&dev_priv->drm, "FDI mPHY reset assert timeout\n");
intel_de_rmw(dev_priv, SOUTH_CHICKEN2, FDI_MPHY_IOSFSB_RESET_CTL, 0);
if (wait_for_us((intel_de_read(dev_priv, SOUTH_CHICKEN2) &
FDI_MPHY_IOSFSB_RESET_STATUS) == 0, 100))
drm_err(&dev_priv->drm, "FDI mPHY reset de-assert timeout\n");
}
/* WaMPhyProgramming:hsw */
static void lpt_fdi_program_mphy(struct drm_i915_private *dev_priv)
{
u32 tmp;
lpt_fdi_reset_mphy(dev_priv);
tmp = intel_sbi_read(dev_priv, 0x8008, SBI_MPHY);
tmp &= ~(0xFF << 24);
tmp |= (0x12 << 24);
intel_sbi_write(dev_priv, 0x8008, tmp, SBI_MPHY);
tmp = intel_sbi_read(dev_priv, 0x2008, SBI_MPHY);
tmp |= (1 << 11);
intel_sbi_write(dev_priv, 0x2008, tmp, SBI_MPHY);
tmp = intel_sbi_read(dev_priv, 0x2108, SBI_MPHY);
tmp |= (1 << 11);
intel_sbi_write(dev_priv, 0x2108, tmp, SBI_MPHY);
tmp = intel_sbi_read(dev_priv, 0x206C, SBI_MPHY);
tmp |= (1 << 24) | (1 << 21) | (1 << 18);
intel_sbi_write(dev_priv, 0x206C, tmp, SBI_MPHY);
tmp = intel_sbi_read(dev_priv, 0x216C, SBI_MPHY);
tmp |= (1 << 24) | (1 << 21) | (1 << 18);
intel_sbi_write(dev_priv, 0x216C, tmp, SBI_MPHY);
tmp = intel_sbi_read(dev_priv, 0x2080, SBI_MPHY);
tmp &= ~(7 << 13);
tmp |= (5 << 13);
intel_sbi_write(dev_priv, 0x2080, tmp, SBI_MPHY);
tmp = intel_sbi_read(dev_priv, 0x2180, SBI_MPHY);
tmp &= ~(7 << 13);
tmp |= (5 << 13);
intel_sbi_write(dev_priv, 0x2180, tmp, SBI_MPHY);
tmp = intel_sbi_read(dev_priv, 0x208C, SBI_MPHY);
tmp &= ~0xFF;
tmp |= 0x1C;
intel_sbi_write(dev_priv, 0x208C, tmp, SBI_MPHY);
tmp = intel_sbi_read(dev_priv, 0x218C, SBI_MPHY);
tmp &= ~0xFF;
tmp |= 0x1C;
intel_sbi_write(dev_priv, 0x218C, tmp, SBI_MPHY);
tmp = intel_sbi_read(dev_priv, 0x2098, SBI_MPHY);
tmp &= ~(0xFF << 16);
tmp |= (0x1C << 16);
intel_sbi_write(dev_priv, 0x2098, tmp, SBI_MPHY);
tmp = intel_sbi_read(dev_priv, 0x2198, SBI_MPHY);
tmp &= ~(0xFF << 16);
tmp |= (0x1C << 16);
intel_sbi_write(dev_priv, 0x2198, tmp, SBI_MPHY);
tmp = intel_sbi_read(dev_priv, 0x20C4, SBI_MPHY);
tmp |= (1 << 27);
intel_sbi_write(dev_priv, 0x20C4, tmp, SBI_MPHY);
tmp = intel_sbi_read(dev_priv, 0x21C4, SBI_MPHY);
tmp |= (1 << 27);
intel_sbi_write(dev_priv, 0x21C4, tmp, SBI_MPHY);
tmp = intel_sbi_read(dev_priv, 0x20EC, SBI_MPHY);
tmp &= ~(0xF << 28);
tmp |= (4 << 28);
intel_sbi_write(dev_priv, 0x20EC, tmp, SBI_MPHY);
tmp = intel_sbi_read(dev_priv, 0x21EC, SBI_MPHY);
tmp &= ~(0xF << 28);
tmp |= (4 << 28);
intel_sbi_write(dev_priv, 0x21EC, tmp, SBI_MPHY);
}
void lpt_disable_iclkip(struct drm_i915_private *dev_priv)
{
u32 temp;
intel_de_write(dev_priv, PIXCLK_GATE, PIXCLK_GATE_GATE);
mutex_lock(&dev_priv->sb_lock);
temp = intel_sbi_read(dev_priv, SBI_SSCCTL6, SBI_ICLK);
temp |= SBI_SSCCTL_DISABLE;
intel_sbi_write(dev_priv, SBI_SSCCTL6, temp, SBI_ICLK);
mutex_unlock(&dev_priv->sb_lock);
}
struct iclkip_params {
u32 iclk_virtual_root_freq;
u32 iclk_pi_range;
u32 divsel, phaseinc, auxdiv, phasedir, desired_divisor;
};
static void iclkip_params_init(struct iclkip_params *p)
{
memset(p, 0, sizeof(*p));
p->iclk_virtual_root_freq = 172800 * 1000;
p->iclk_pi_range = 64;
}
static int lpt_iclkip_freq(struct iclkip_params *p)
{
return DIV_ROUND_CLOSEST(p->iclk_virtual_root_freq,
p->desired_divisor << p->auxdiv);
}
static void lpt_compute_iclkip(struct iclkip_params *p, int clock)
{
iclkip_params_init(p);
/* The iCLK virtual clock root frequency is in MHz,
* but the adjusted_mode->crtc_clock in KHz. To get the
* divisors, it is necessary to divide one by another, so we
* convert the virtual clock precision to KHz here for higher
* precision.
*/
for (p->auxdiv = 0; p->auxdiv < 2; p->auxdiv++) {
p->desired_divisor = DIV_ROUND_CLOSEST(p->iclk_virtual_root_freq,
clock << p->auxdiv);
p->divsel = (p->desired_divisor / p->iclk_pi_range) - 2;
p->phaseinc = p->desired_divisor % p->iclk_pi_range;
/*
* Near 20MHz is a corner case which is
* out of range for the 7-bit divisor
*/
if (p->divsel <= 0x7f)
break;
}
}
int lpt_iclkip(const struct intel_crtc_state *crtc_state)
{
struct iclkip_params p;
lpt_compute_iclkip(&p, crtc_state->hw.adjusted_mode.crtc_clock);
return lpt_iclkip_freq(&p);
}
/* Program iCLKIP clock to the desired frequency */
void lpt_program_iclkip(const struct intel_crtc_state *crtc_state)
{
struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
int clock = crtc_state->hw.adjusted_mode.crtc_clock;
struct iclkip_params p;
u32 temp;
lpt_disable_iclkip(dev_priv);
lpt_compute_iclkip(&p, clock);
drm_WARN_ON(&dev_priv->drm, lpt_iclkip_freq(&p) != clock);
/* This should not happen with any sane values */
drm_WARN_ON(&dev_priv->drm, SBI_SSCDIVINTPHASE_DIVSEL(p.divsel) &
~SBI_SSCDIVINTPHASE_DIVSEL_MASK);
drm_WARN_ON(&dev_priv->drm, SBI_SSCDIVINTPHASE_DIR(p.phasedir) &
~SBI_SSCDIVINTPHASE_INCVAL_MASK);
drm_dbg_kms(&dev_priv->drm,
"iCLKIP clock: found settings for %dKHz refresh rate: auxdiv=%x, divsel=%x, phasedir=%x, phaseinc=%x\n",
clock, p.auxdiv, p.divsel, p.phasedir, p.phaseinc);
mutex_lock(&dev_priv->sb_lock);
/* Program SSCDIVINTPHASE6 */
temp = intel_sbi_read(dev_priv, SBI_SSCDIVINTPHASE6, SBI_ICLK);
temp &= ~SBI_SSCDIVINTPHASE_DIVSEL_MASK;
temp |= SBI_SSCDIVINTPHASE_DIVSEL(p.divsel);
temp &= ~SBI_SSCDIVINTPHASE_INCVAL_MASK;
temp |= SBI_SSCDIVINTPHASE_INCVAL(p.phaseinc);
temp |= SBI_SSCDIVINTPHASE_DIR(p.phasedir);
temp |= SBI_SSCDIVINTPHASE_PROPAGATE;
intel_sbi_write(dev_priv, SBI_SSCDIVINTPHASE6, temp, SBI_ICLK);
/* Program SSCAUXDIV */
temp = intel_sbi_read(dev_priv, SBI_SSCAUXDIV6, SBI_ICLK);
temp &= ~SBI_SSCAUXDIV_FINALDIV2SEL(1);
temp |= SBI_SSCAUXDIV_FINALDIV2SEL(p.auxdiv);
intel_sbi_write(dev_priv, SBI_SSCAUXDIV6, temp, SBI_ICLK);
/* Enable modulator and associated divider */
temp = intel_sbi_read(dev_priv, SBI_SSCCTL6, SBI_ICLK);
temp &= ~SBI_SSCCTL_DISABLE;
intel_sbi_write(dev_priv, SBI_SSCCTL6, temp, SBI_ICLK);
mutex_unlock(&dev_priv->sb_lock);
/* Wait for initialization time */
udelay(24);
intel_de_write(dev_priv, PIXCLK_GATE, PIXCLK_GATE_UNGATE);
}
int lpt_get_iclkip(struct drm_i915_private *dev_priv)
{
struct iclkip_params p;
u32 temp;
if ((intel_de_read(dev_priv, PIXCLK_GATE) & PIXCLK_GATE_UNGATE) == 0)
return 0;
iclkip_params_init(&p);
mutex_lock(&dev_priv->sb_lock);
temp = intel_sbi_read(dev_priv, SBI_SSCCTL6, SBI_ICLK);
if (temp & SBI_SSCCTL_DISABLE) {
mutex_unlock(&dev_priv->sb_lock);
return 0;
}
temp = intel_sbi_read(dev_priv, SBI_SSCDIVINTPHASE6, SBI_ICLK);
p.divsel = (temp & SBI_SSCDIVINTPHASE_DIVSEL_MASK) >>
SBI_SSCDIVINTPHASE_DIVSEL_SHIFT;
p.phaseinc = (temp & SBI_SSCDIVINTPHASE_INCVAL_MASK) >>
SBI_SSCDIVINTPHASE_INCVAL_SHIFT;
temp = intel_sbi_read(dev_priv, SBI_SSCAUXDIV6, SBI_ICLK);
p.auxdiv = (temp & SBI_SSCAUXDIV_FINALDIV2SEL_MASK) >>
SBI_SSCAUXDIV_FINALDIV2SEL_SHIFT;
mutex_unlock(&dev_priv->sb_lock);
p.desired_divisor = (p.divsel + 2) * p.iclk_pi_range + p.phaseinc;
return lpt_iclkip_freq(&p);
}
/* Implements 3 different sequences from BSpec chapter "Display iCLK
* Programming" based on the parameters passed:
* - Sequence to enable CLKOUT_DP
* - Sequence to enable CLKOUT_DP without spread
* - Sequence to enable CLKOUT_DP for FDI usage and configure PCH FDI I/O
*/
static void lpt_enable_clkout_dp(struct drm_i915_private *dev_priv,
bool with_spread, bool with_fdi)
{
u32 reg, tmp;
if (drm_WARN(&dev_priv->drm, with_fdi && !with_spread,
"FDI requires downspread\n"))
with_spread = true;
if (drm_WARN(&dev_priv->drm, HAS_PCH_LPT_LP(dev_priv) &&
with_fdi, "LP PCH doesn't have FDI\n"))
with_fdi = false;
mutex_lock(&dev_priv->sb_lock);
tmp = intel_sbi_read(dev_priv, SBI_SSCCTL, SBI_ICLK);
tmp &= ~SBI_SSCCTL_DISABLE;
tmp |= SBI_SSCCTL_PATHALT;
intel_sbi_write(dev_priv, SBI_SSCCTL, tmp, SBI_ICLK);
udelay(24);
if (with_spread) {
tmp = intel_sbi_read(dev_priv, SBI_SSCCTL, SBI_ICLK);
tmp &= ~SBI_SSCCTL_PATHALT;
intel_sbi_write(dev_priv, SBI_SSCCTL, tmp, SBI_ICLK);
if (with_fdi)
lpt_fdi_program_mphy(dev_priv);
}
reg = HAS_PCH_LPT_LP(dev_priv) ? SBI_GEN0 : SBI_DBUFF0;
tmp = intel_sbi_read(dev_priv, reg, SBI_ICLK);
tmp |= SBI_GEN0_CFG_BUFFENABLE_DISABLE;
intel_sbi_write(dev_priv, reg, tmp, SBI_ICLK);
mutex_unlock(&dev_priv->sb_lock);
}
/* Sequence to disable CLKOUT_DP */
void lpt_disable_clkout_dp(struct drm_i915_private *dev_priv)
{
u32 reg, tmp;
mutex_lock(&dev_priv->sb_lock);
reg = HAS_PCH_LPT_LP(dev_priv) ? SBI_GEN0 : SBI_DBUFF0;
tmp = intel_sbi_read(dev_priv, reg, SBI_ICLK);
tmp &= ~SBI_GEN0_CFG_BUFFENABLE_DISABLE;
intel_sbi_write(dev_priv, reg, tmp, SBI_ICLK);
tmp = intel_sbi_read(dev_priv, SBI_SSCCTL, SBI_ICLK);
if (!(tmp & SBI_SSCCTL_DISABLE)) {
if (!(tmp & SBI_SSCCTL_PATHALT)) {
tmp |= SBI_SSCCTL_PATHALT;
intel_sbi_write(dev_priv, SBI_SSCCTL, tmp, SBI_ICLK);
udelay(32);
}
tmp |= SBI_SSCCTL_DISABLE;
intel_sbi_write(dev_priv, SBI_SSCCTL, tmp, SBI_ICLK);
}
mutex_unlock(&dev_priv->sb_lock);
}
#define BEND_IDX(steps) ((50 + (steps)) / 5)
static const u16 sscdivintphase[] = {
[BEND_IDX( 50)] = 0x3B23,
[BEND_IDX( 45)] = 0x3B23,
[BEND_IDX( 40)] = 0x3C23,
[BEND_IDX( 35)] = 0x3C23,
[BEND_IDX( 30)] = 0x3D23,
[BEND_IDX( 25)] = 0x3D23,
[BEND_IDX( 20)] = 0x3E23,
[BEND_IDX( 15)] = 0x3E23,
[BEND_IDX( 10)] = 0x3F23,
[BEND_IDX( 5)] = 0x3F23,
[BEND_IDX( 0)] = 0x0025,
[BEND_IDX( -5)] = 0x0025,
[BEND_IDX(-10)] = 0x0125,
[BEND_IDX(-15)] = 0x0125,
[BEND_IDX(-20)] = 0x0225,
[BEND_IDX(-25)] = 0x0225,
[BEND_IDX(-30)] = 0x0325,
[BEND_IDX(-35)] = 0x0325,
[BEND_IDX(-40)] = 0x0425,
[BEND_IDX(-45)] = 0x0425,
[BEND_IDX(-50)] = 0x0525,
};
/*
* Bend CLKOUT_DP
* steps -50 to 50 inclusive, in steps of 5
* < 0 slow down the clock, > 0 speed up the clock, 0 == no bend (135MHz)
* change in clock period = -(steps / 10) * 5.787 ps
*/
static void lpt_bend_clkout_dp(struct drm_i915_private *dev_priv, int steps)
{
u32 tmp;
int idx = BEND_IDX(steps);
if (drm_WARN_ON(&dev_priv->drm, steps % 5 != 0))
return;
if (drm_WARN_ON(&dev_priv->drm, idx >= ARRAY_SIZE(sscdivintphase)))
return;
mutex_lock(&dev_priv->sb_lock);
if (steps % 10 != 0)
tmp = 0xAAAAAAAB;
else
tmp = 0x00000000;
intel_sbi_write(dev_priv, SBI_SSCDITHPHASE, tmp, SBI_ICLK);
tmp = intel_sbi_read(dev_priv, SBI_SSCDIVINTPHASE, SBI_ICLK);
tmp &= 0xffff0000;
tmp |= sscdivintphase[idx];
intel_sbi_write(dev_priv, SBI_SSCDIVINTPHASE, tmp, SBI_ICLK);
mutex_unlock(&dev_priv->sb_lock);
}
#undef BEND_IDX
static bool spll_uses_pch_ssc(struct drm_i915_private *dev_priv)
{
u32 fuse_strap = intel_de_read(dev_priv, FUSE_STRAP);
u32 ctl = intel_de_read(dev_priv, SPLL_CTL);
if ((ctl & SPLL_PLL_ENABLE) == 0)
return false;
if ((ctl & SPLL_REF_MASK) == SPLL_REF_MUXED_SSC &&
(fuse_strap & HSW_CPU_SSC_ENABLE) == 0)
return true;
if (IS_BROADWELL(dev_priv) &&
(ctl & SPLL_REF_MASK) == SPLL_REF_PCH_SSC_BDW)
return true;
return false;
}
static bool wrpll_uses_pch_ssc(struct drm_i915_private *dev_priv,
enum intel_dpll_id id)
{
u32 fuse_strap = intel_de_read(dev_priv, FUSE_STRAP);
u32 ctl = intel_de_read(dev_priv, WRPLL_CTL(id));
if ((ctl & WRPLL_PLL_ENABLE) == 0)
return false;
if ((ctl & WRPLL_REF_MASK) == WRPLL_REF_PCH_SSC)
return true;
if ((IS_BROADWELL(dev_priv) || IS_HASWELL_ULT(dev_priv)) &&
(ctl & WRPLL_REF_MASK) == WRPLL_REF_MUXED_SSC_BDW &&
(fuse_strap & HSW_CPU_SSC_ENABLE) == 0)
return true;
return false;
}
static void lpt_init_pch_refclk(struct drm_i915_private *dev_priv)
{
struct intel_encoder *encoder;
bool has_fdi = false;
for_each_intel_encoder(&dev_priv->drm, encoder) {
switch (encoder->type) {
case INTEL_OUTPUT_ANALOG:
has_fdi = true;
break;
default:
break;
}
}
/*
* The BIOS may have decided to use the PCH SSC
* reference so we must not disable it until the
* relevant PLLs have stopped relying on it. We'll
* just leave the PCH SSC reference enabled in case
* any active PLL is using it. It will get disabled
* after runtime suspend if we don't have FDI.
*
* TODO: Move the whole reference clock handling
* to the modeset sequence proper so that we can
* actually enable/disable/reconfigure these things
* safely. To do that we need to introduce a real
* clock hierarchy. That would also allow us to do
* clock bending finally.
*/
dev_priv->display.dpll.pch_ssc_use = 0;
if (spll_uses_pch_ssc(dev_priv)) {
drm_dbg_kms(&dev_priv->drm, "SPLL using PCH SSC\n");
dev_priv->display.dpll.pch_ssc_use |= BIT(DPLL_ID_SPLL);
}
if (wrpll_uses_pch_ssc(dev_priv, DPLL_ID_WRPLL1)) {
drm_dbg_kms(&dev_priv->drm, "WRPLL1 using PCH SSC\n");
dev_priv->display.dpll.pch_ssc_use |= BIT(DPLL_ID_WRPLL1);
}
if (wrpll_uses_pch_ssc(dev_priv, DPLL_ID_WRPLL2)) {
drm_dbg_kms(&dev_priv->drm, "WRPLL2 using PCH SSC\n");
dev_priv->display.dpll.pch_ssc_use |= BIT(DPLL_ID_WRPLL2);
}
if (dev_priv->display.dpll.pch_ssc_use)
return;
if (has_fdi) {
lpt_bend_clkout_dp(dev_priv, 0);
lpt_enable_clkout_dp(dev_priv, true, true);
} else {
lpt_disable_clkout_dp(dev_priv);
}
}
static void ilk_init_pch_refclk(struct drm_i915_private *dev_priv)
{
struct intel_encoder *encoder;
struct intel_shared_dpll *pll;
int i;
u32 val, final;
bool has_lvds = false;
bool has_cpu_edp = false;
bool has_panel = false;
bool has_ck505 = false;
bool can_ssc = false;
bool using_ssc_source = false;
/* We need to take the global config into account */
for_each_intel_encoder(&dev_priv->drm, encoder) {
switch (encoder->type) {
case INTEL_OUTPUT_LVDS:
has_panel = true;
has_lvds = true;
break;
case INTEL_OUTPUT_EDP:
has_panel = true;
if (encoder->port == PORT_A)
has_cpu_edp = true;
break;
default:
break;
}
}
if (HAS_PCH_IBX(dev_priv)) {
has_ck505 = dev_priv->display.vbt.display_clock_mode;
can_ssc = has_ck505;
} else {
has_ck505 = false;
can_ssc = true;
}
/* Check if any DPLLs are using the SSC source */
for_each_shared_dpll(dev_priv, pll, i) {
u32 temp;
temp = intel_de_read(dev_priv, PCH_DPLL(pll->info->id));
if (!(temp & DPLL_VCO_ENABLE))
continue;
if ((temp & PLL_REF_INPUT_MASK) ==
PLLB_REF_INPUT_SPREADSPECTRUMIN) {
using_ssc_source = true;
break;
}
}
drm_dbg_kms(&dev_priv->drm,
"has_panel %d has_lvds %d has_ck505 %d using_ssc_source %d\n",
has_panel, has_lvds, has_ck505, using_ssc_source);
/* Ironlake: try to setup display ref clock before DPLL
* enabling. This is only under driver's control after
* PCH B stepping, previous chipset stepping should be
* ignoring this setting.
*/
val = intel_de_read(dev_priv, PCH_DREF_CONTROL);
/* As we must carefully and slowly disable/enable each source in turn,
* compute the final state we want first and check if we need to
* make any changes at all.
*/
final = val;
final &= ~DREF_NONSPREAD_SOURCE_MASK;
if (has_ck505)
final |= DREF_NONSPREAD_CK505_ENABLE;
else
final |= DREF_NONSPREAD_SOURCE_ENABLE;
final &= ~DREF_SSC_SOURCE_MASK;
final &= ~DREF_CPU_SOURCE_OUTPUT_MASK;
final &= ~DREF_SSC1_ENABLE;
if (has_panel) {
final |= DREF_SSC_SOURCE_ENABLE;
if (intel_panel_use_ssc(dev_priv) && can_ssc)
final |= DREF_SSC1_ENABLE;
if (has_cpu_edp) {
if (intel_panel_use_ssc(dev_priv) && can_ssc)
final |= DREF_CPU_SOURCE_OUTPUT_DOWNSPREAD;
else
final |= DREF_CPU_SOURCE_OUTPUT_NONSPREAD;
} else {
final |= DREF_CPU_SOURCE_OUTPUT_DISABLE;
}
} else if (using_ssc_source) {
final |= DREF_SSC_SOURCE_ENABLE;
final |= DREF_SSC1_ENABLE;
}
if (final == val)
return;
/* Always enable nonspread source */
val &= ~DREF_NONSPREAD_SOURCE_MASK;
if (has_ck505)
val |= DREF_NONSPREAD_CK505_ENABLE;
else
val |= DREF_NONSPREAD_SOURCE_ENABLE;
if (has_panel) {
val &= ~DREF_SSC_SOURCE_MASK;
val |= DREF_SSC_SOURCE_ENABLE;
/* SSC must be turned on before enabling the CPU output */
if (intel_panel_use_ssc(dev_priv) && can_ssc) {
drm_dbg_kms(&dev_priv->drm, "Using SSC on panel\n");
val |= DREF_SSC1_ENABLE;
} else {
val &= ~DREF_SSC1_ENABLE;
}
/* Get SSC going before enabling the outputs */
intel_de_write(dev_priv, PCH_DREF_CONTROL, val);
intel_de_posting_read(dev_priv, PCH_DREF_CONTROL);
udelay(200);
val &= ~DREF_CPU_SOURCE_OUTPUT_MASK;
/* Enable CPU source on CPU attached eDP */
if (has_cpu_edp) {
if (intel_panel_use_ssc(dev_priv) && can_ssc) {
drm_dbg_kms(&dev_priv->drm,
"Using SSC on eDP\n");
val |= DREF_CPU_SOURCE_OUTPUT_DOWNSPREAD;
} else {
val |= DREF_CPU_SOURCE_OUTPUT_NONSPREAD;
}
} else {
val |= DREF_CPU_SOURCE_OUTPUT_DISABLE;
}
intel_de_write(dev_priv, PCH_DREF_CONTROL, val);
intel_de_posting_read(dev_priv, PCH_DREF_CONTROL);
udelay(200);
} else {
drm_dbg_kms(&dev_priv->drm, "Disabling CPU source output\n");
val &= ~DREF_CPU_SOURCE_OUTPUT_MASK;
/* Turn off CPU output */
val |= DREF_CPU_SOURCE_OUTPUT_DISABLE;
intel_de_write(dev_priv, PCH_DREF_CONTROL, val);
intel_de_posting_read(dev_priv, PCH_DREF_CONTROL);
udelay(200);
if (!using_ssc_source) {
drm_dbg_kms(&dev_priv->drm, "Disabling SSC source\n");
/* Turn off the SSC source */
val &= ~DREF_SSC_SOURCE_MASK;
val |= DREF_SSC_SOURCE_DISABLE;
/* Turn off SSC1 */
val &= ~DREF_SSC1_ENABLE;
intel_de_write(dev_priv, PCH_DREF_CONTROL, val);
intel_de_posting_read(dev_priv, PCH_DREF_CONTROL);
udelay(200);
}
}
drm_WARN_ON(&dev_priv->drm, val != final);
}
/*
* Initialize reference clocks when the driver loads
*/
void intel_init_pch_refclk(struct drm_i915_private *dev_priv)
{
if (HAS_PCH_IBX(dev_priv) || HAS_PCH_CPT(dev_priv))
ilk_init_pch_refclk(dev_priv);
else if (HAS_PCH_LPT(dev_priv))
lpt_init_pch_refclk(dev_priv);
}