@@ -200,6 +200,14 @@
#define XELPDP_SSC_ENABLE_PLLA REG_BIT(1)
#define XELPDP_SSC_ENABLE_PLLB REG_BIT(0)
+#define TCSS_DISP_MAILBOX_IN_CMD _MMIO(0x161300)
+#define TCSS_DISP_MAILBOX_IN_CMD_RUN_BUSY REG_BIT(31)
+#define TCSS_DISP_MAILBOX_IN_CMD_CMD_MASK REG_GENMASK(7, 0)
+#define TCSS_DISP_MAILBOX_IN_CMD_DATA(val) (TCSS_DISP_MAILBOX_IN_CMD_RUN_BUSY | \
+ REG_FIELD_PREP(TCSS_DISP_MAILBOX_IN_CMD_CMD_MASK, val))
+
+#define TCSS_DISP_MAILBOX_IN_DATA _MMIO(0x161304)
+
/* C10 Vendor Registers */
#define PHY_C10_VDR_PLL(idx) (0xC00 + (idx))
#define C10_PLL0_FRACEN REG_BIT8(4)
@@ -1013,6 +1013,30 @@ xelpdp_tc_phy_wait_for_tcss_power(struct intel_tc_port *tc, bool enabled)
return true;
}
+static void wa_14020908590(struct intel_display *display, bool enable)
+{
+ /* check if mailbox is running busy */
+ if (intel_de_wait_for_clear(display, TCSS_DISP_MAILBOX_IN_CMD,
+ TCSS_DISP_MAILBOX_IN_CMD_RUN_BUSY, 10)) {
+ drm_dbg_kms(display->drm,
+ "Timeout waiting for TCSS mailbox run/busy bit to clear\n");
+ return;
+ }
+
+ intel_de_write(display, TCSS_DISP_MAILBOX_IN_DATA, enable);
+ intel_de_write(display, TCSS_DISP_MAILBOX_IN_CMD,
+ TCSS_DISP_MAILBOX_IN_CMD_RUN_BUSY |
+ TCSS_DISP_MAILBOX_IN_CMD_DATA(0x1));
+
+ /* wait to clear mailbox running busy bit before continuing */
+ if (intel_de_wait_for_clear(display, TCSS_DISP_MAILBOX_IN_CMD,
+ TCSS_DISP_MAILBOX_IN_CMD_RUN_BUSY, 10)) {
+ drm_dbg_kms(display->drm,
+ "Timeout after writing data to mailbox. Mailbox run/busy bit did not clear\n");
+ return;
+ }
+}
+
static void __xelpdp_tc_phy_enable_tcss_power(struct intel_tc_port *tc, bool enable)
{
struct drm_i915_private *i915 = tc_to_i915(tc);
@@ -1022,6 +1046,13 @@ static void __xelpdp_tc_phy_enable_tcss_power(struct intel_tc_port *tc, bool ena
assert_tc_cold_blocked(tc);
+ /*
+ * Gfx driver WA 14020908590 for PTL tcss_rxdetect_clkswb_req/ack
+ * handshake violation when pwwreq= 0->1 during TC7/10 entry
+ */
+ if (DISPLAY_VER(i915) == 30)
+ wa_14020908590(&i915->display, enable);
+
val = intel_de_read(i915, reg);
if (enable)
val |= XELPDP_TCSS_POWER_REQUEST;
There is a HW issue that arises when there are race conditions between TCSS entering/exiting TC7 or TC10 states while the driver is asserting/deasserting TCSS power request. As a workaround, Display driver will implement a mailbox sequence to ensure that the TCSS is in TC0 when TCSS power request is asserted/deasserted. The sequence is the following 1. Read mailbox command status and wait until run/busy bit is clear 2. Write mailbox data value '1' for power request asserting and '0' for power request deasserting 3. Write mailbox command run/busy bit and command value with 0x1 4. Read mailbox command and wait until run/busy bit is clear before continuing power request. v2: Rename WA function (Gustavo) Limit WA only for PTL platform with a TODO note (Gustavo) Add TCSS_DISP_MAILBOX_IN_CMD_RUN_BUSY for clarity when writing register data (Gustavo) Move register defs from i915_reg.h to intel_cx0_phy_regs.h (Gustavo) v3: Use "struct intel_display" instead of "struct drm_i915_private" (Jani) Move defs above C10 definitions in the intel_cx0_phy_regs.h file (Gustavo) Move drm_WARN_ON() inside WA function (Gustavo) Rename workaround function as wa_14020908590() (Gustvo) Use boolean enable instead of if-else structure (Raag) v4: Drop drm_WARN_ON() (Raag) Fix function definition to fit into a single line (Raag) Reviewed-by: Raag Jadav <raag.jadav@intel.com> Signed-off-by: Mika Kahola <mika.kahola@intel.com> --- .../gpu/drm/i915/display/intel_cx0_phy_regs.h | 8 +++++ drivers/gpu/drm/i915/display/intel_tc.c | 31 +++++++++++++++++++ 2 files changed, 39 insertions(+)