summaryrefslogtreecommitdiffstats
path: root/drivers/gpu/drm/i915/vlv_sideband.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/gpu/drm/i915/vlv_sideband.c')
-rw-r--r--drivers/gpu/drm/i915/vlv_sideband.c266
1 files changed, 266 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/vlv_sideband.c b/drivers/gpu/drm/i915/vlv_sideband.c
new file mode 100644
index 000000000..c26001300
--- /dev/null
+++ b/drivers/gpu/drm/i915/vlv_sideband.c
@@ -0,0 +1,266 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2013-2021 Intel Corporation
+ */
+
+#include "i915_drv.h"
+#include "i915_iosf_mbi.h"
+#include "i915_reg.h"
+#include "vlv_sideband.h"
+
+/*
+ * IOSF sideband, see VLV2_SidebandMsg_HAS.docx and
+ * VLV_VLV2_PUNIT_HAS_0.8.docx
+ */
+
+/* Standard MMIO read, non-posted */
+#define SB_MRD_NP 0x00
+/* Standard MMIO write, non-posted */
+#define SB_MWR_NP 0x01
+/* Private register read, double-word addressing, non-posted */
+#define SB_CRRDDA_NP 0x06
+/* Private register write, double-word addressing, non-posted */
+#define SB_CRWRDA_NP 0x07
+
+static void ping(void *info)
+{
+}
+
+static void __vlv_punit_get(struct drm_i915_private *i915)
+{
+ iosf_mbi_punit_acquire();
+
+ /*
+ * Prevent the cpu from sleeping while we use this sideband, otherwise
+ * the punit may cause a machine hang. The issue appears to be isolated
+ * with changing the power state of the CPU package while changing
+ * the power state via the punit, and we have only observed it
+ * reliably on 4-core Baytail systems suggesting the issue is in the
+ * power delivery mechanism and likely to be board/function
+ * specific. Hence we presume the workaround needs only be applied
+ * to the Valleyview P-unit and not all sideband communications.
+ */
+ if (IS_VALLEYVIEW(i915)) {
+ cpu_latency_qos_update_request(&i915->sb_qos, 0);
+ on_each_cpu(ping, NULL, 1);
+ }
+}
+
+static void __vlv_punit_put(struct drm_i915_private *i915)
+{
+ if (IS_VALLEYVIEW(i915))
+ cpu_latency_qos_update_request(&i915->sb_qos,
+ PM_QOS_DEFAULT_VALUE);
+
+ iosf_mbi_punit_release();
+}
+
+void vlv_iosf_sb_get(struct drm_i915_private *i915, unsigned long ports)
+{
+ if (ports & BIT(VLV_IOSF_SB_PUNIT))
+ __vlv_punit_get(i915);
+
+ mutex_lock(&i915->sb_lock);
+}
+
+void vlv_iosf_sb_put(struct drm_i915_private *i915, unsigned long ports)
+{
+ mutex_unlock(&i915->sb_lock);
+
+ if (ports & BIT(VLV_IOSF_SB_PUNIT))
+ __vlv_punit_put(i915);
+}
+
+static int vlv_sideband_rw(struct drm_i915_private *i915,
+ u32 devfn, u32 port, u32 opcode,
+ u32 addr, u32 *val)
+{
+ struct intel_uncore *uncore = &i915->uncore;
+ const bool is_read = (opcode == SB_MRD_NP || opcode == SB_CRRDDA_NP);
+ int err;
+
+ lockdep_assert_held(&i915->sb_lock);
+ if (port == IOSF_PORT_PUNIT)
+ iosf_mbi_assert_punit_acquired();
+
+ /* Flush the previous comms, just in case it failed last time. */
+ if (intel_wait_for_register(uncore,
+ VLV_IOSF_DOORBELL_REQ, IOSF_SB_BUSY, 0,
+ 5)) {
+ drm_dbg(&i915->drm, "IOSF sideband idle wait (%s) timed out\n",
+ is_read ? "read" : "write");
+ return -EAGAIN;
+ }
+
+ preempt_disable();
+
+ intel_uncore_write_fw(uncore, VLV_IOSF_ADDR, addr);
+ intel_uncore_write_fw(uncore, VLV_IOSF_DATA, is_read ? 0 : *val);
+ intel_uncore_write_fw(uncore, VLV_IOSF_DOORBELL_REQ,
+ (devfn << IOSF_DEVFN_SHIFT) |
+ (opcode << IOSF_OPCODE_SHIFT) |
+ (port << IOSF_PORT_SHIFT) |
+ (0xf << IOSF_BYTE_ENABLES_SHIFT) |
+ (0 << IOSF_BAR_SHIFT) |
+ IOSF_SB_BUSY);
+
+ if (__intel_wait_for_register_fw(uncore,
+ VLV_IOSF_DOORBELL_REQ, IOSF_SB_BUSY, 0,
+ 10000, 0, NULL) == 0) {
+ if (is_read)
+ *val = intel_uncore_read_fw(uncore, VLV_IOSF_DATA);
+ err = 0;
+ } else {
+ drm_dbg(&i915->drm, "IOSF sideband finish wait (%s) timed out\n",
+ is_read ? "read" : "write");
+ err = -ETIMEDOUT;
+ }
+
+ preempt_enable();
+
+ return err;
+}
+
+u32 vlv_punit_read(struct drm_i915_private *i915, u32 addr)
+{
+ u32 val = 0;
+
+ vlv_sideband_rw(i915, PCI_DEVFN(0, 0), IOSF_PORT_PUNIT,
+ SB_CRRDDA_NP, addr, &val);
+
+ return val;
+}
+
+int vlv_punit_write(struct drm_i915_private *i915, u32 addr, u32 val)
+{
+ return vlv_sideband_rw(i915, PCI_DEVFN(0, 0), IOSF_PORT_PUNIT,
+ SB_CRWRDA_NP, addr, &val);
+}
+
+u32 vlv_bunit_read(struct drm_i915_private *i915, u32 reg)
+{
+ u32 val = 0;
+
+ vlv_sideband_rw(i915, PCI_DEVFN(0, 0), IOSF_PORT_BUNIT,
+ SB_CRRDDA_NP, reg, &val);
+
+ return val;
+}
+
+void vlv_bunit_write(struct drm_i915_private *i915, u32 reg, u32 val)
+{
+ vlv_sideband_rw(i915, PCI_DEVFN(0, 0), IOSF_PORT_BUNIT,
+ SB_CRWRDA_NP, reg, &val);
+}
+
+u32 vlv_nc_read(struct drm_i915_private *i915, u8 addr)
+{
+ u32 val = 0;
+
+ vlv_sideband_rw(i915, PCI_DEVFN(0, 0), IOSF_PORT_NC,
+ SB_CRRDDA_NP, addr, &val);
+
+ return val;
+}
+
+u32 vlv_iosf_sb_read(struct drm_i915_private *i915, u8 port, u32 reg)
+{
+ u32 val = 0;
+
+ vlv_sideband_rw(i915, PCI_DEVFN(0, 0), port,
+ SB_CRRDDA_NP, reg, &val);
+
+ return val;
+}
+
+void vlv_iosf_sb_write(struct drm_i915_private *i915,
+ u8 port, u32 reg, u32 val)
+{
+ vlv_sideband_rw(i915, PCI_DEVFN(0, 0), port,
+ SB_CRWRDA_NP, reg, &val);
+}
+
+u32 vlv_cck_read(struct drm_i915_private *i915, u32 reg)
+{
+ u32 val = 0;
+
+ vlv_sideband_rw(i915, PCI_DEVFN(0, 0), IOSF_PORT_CCK,
+ SB_CRRDDA_NP, reg, &val);
+
+ return val;
+}
+
+void vlv_cck_write(struct drm_i915_private *i915, u32 reg, u32 val)
+{
+ vlv_sideband_rw(i915, PCI_DEVFN(0, 0), IOSF_PORT_CCK,
+ SB_CRWRDA_NP, reg, &val);
+}
+
+u32 vlv_ccu_read(struct drm_i915_private *i915, u32 reg)
+{
+ u32 val = 0;
+
+ vlv_sideband_rw(i915, PCI_DEVFN(0, 0), IOSF_PORT_CCU,
+ SB_CRRDDA_NP, reg, &val);
+
+ return val;
+}
+
+void vlv_ccu_write(struct drm_i915_private *i915, u32 reg, u32 val)
+{
+ vlv_sideband_rw(i915, PCI_DEVFN(0, 0), IOSF_PORT_CCU,
+ SB_CRWRDA_NP, reg, &val);
+}
+
+static u32 vlv_dpio_phy_iosf_port(struct drm_i915_private *i915, enum dpio_phy phy)
+{
+ /*
+ * IOSF_PORT_DPIO: VLV x2 PHY (DP/HDMI B and C), CHV x1 PHY (DP/HDMI D)
+ * IOSF_PORT_DPIO_2: CHV x2 PHY (DP/HDMI B and C)
+ */
+ if (IS_CHERRYVIEW(i915))
+ return phy == DPIO_PHY0 ? IOSF_PORT_DPIO_2 : IOSF_PORT_DPIO;
+ else
+ return IOSF_PORT_DPIO;
+}
+
+u32 vlv_dpio_read(struct drm_i915_private *i915, enum pipe pipe, int reg)
+{
+ u32 port = vlv_dpio_phy_iosf_port(i915, DPIO_PHY(pipe));
+ u32 val = 0;
+
+ vlv_sideband_rw(i915, DPIO_DEVFN, port, SB_MRD_NP, reg, &val);
+
+ /*
+ * FIXME: There might be some registers where all 1's is a valid value,
+ * so ideally we should check the register offset instead...
+ */
+ drm_WARN(&i915->drm, val == 0xffffffff,
+ "DPIO read pipe %c reg 0x%x == 0x%x\n",
+ pipe_name(pipe), reg, val);
+
+ return val;
+}
+
+void vlv_dpio_write(struct drm_i915_private *i915,
+ enum pipe pipe, int reg, u32 val)
+{
+ u32 port = vlv_dpio_phy_iosf_port(i915, DPIO_PHY(pipe));
+
+ vlv_sideband_rw(i915, DPIO_DEVFN, port, SB_MWR_NP, reg, &val);
+}
+
+u32 vlv_flisdsi_read(struct drm_i915_private *i915, u32 reg)
+{
+ u32 val = 0;
+
+ vlv_sideband_rw(i915, DPIO_DEVFN, IOSF_PORT_FLISDSI, SB_CRRDDA_NP,
+ reg, &val);
+ return val;
+}
+
+void vlv_flisdsi_write(struct drm_i915_private *i915, u32 reg, u32 val)
+{
+ vlv_sideband_rw(i915, DPIO_DEVFN, IOSF_PORT_FLISDSI, SB_CRWRDA_NP,
+ reg, &val);
+}