drm/imagination: Implement context creation/destruction ioctls

Implement ioctls for the creation and destruction of contexts. Contexts are
used for job submission and each is associated with a particular job type.

Changes since v8:
- Fixed one error path in pvr_stream_process_1()
- Corrected license identifiers

Changes since v5:
- Fix context release in final error path in pvr_context_create()

Changes since v3:
- Use drm_dev_{enter,exit}

Co-developed-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Signed-off-by: Sarah Walker <sarah.walker@imgtec.com>
Signed-off-by: Donald Robson <donald.robson@imgtec.com>
Link: https://lore.kernel.org/r/ac474a1f7dda2582d290798e4837140a2989aa2a.1700668843.git.donald.robson@imgtec.com
Signed-off-by: Maxime Ripard <mripard@kernel.org>

drivers/gpu/drm/imagination/Makefile

@@ -5,6 +5,8 @@ subdir-ccflags-y := -I$(srctree)/$(src)
 
 powervr-y := \
 	pvr_ccb.o \
+	pvr_cccb.o \
+	pvr_context.o \
 	pvr_device.o \
 	pvr_device_info.o \
 	pvr_drv.o \
@@ -18,6 +20,8 @@ powervr-y := \
 	pvr_hwrt.o \
 	pvr_mmu.o \
 	pvr_power.o \
+	pvr_stream.o \
+	pvr_stream_defs.o \
 	pvr_vm.o \
 	pvr_vm_mips.o
 

drivers/gpu/drm/imagination/pvr_cccb.c

@@ -0,0 +1,267 @@
+// SPDX-License-Identifier: GPL-2.0-only OR MIT
+/* Copyright (c) 2023 Imagination Technologies Ltd. */
+
+#include "pvr_ccb.h"
+#include "pvr_cccb.h"
+#include "pvr_device.h"
+#include "pvr_gem.h"
+#include "pvr_hwrt.h"
+
+#include <linux/compiler.h>
+#include <linux/delay.h>
+#include <linux/jiffies.h>
+#include <linux/mutex.h>
+#include <linux/types.h>
+
+static __always_inline u32
+get_ccb_space(u32 w_off, u32 r_off, u32 ccb_size)
+{
+	return (((r_off) - (w_off)) + ((ccb_size) - 1)) & ((ccb_size) - 1);
+}
+
+static void
+cccb_ctrl_init(void *cpu_ptr, void *priv)
+{
+	struct rogue_fwif_cccb_ctl *ctrl = cpu_ptr;
+	struct pvr_cccb *pvr_cccb = priv;
+
+	WRITE_ONCE(ctrl->write_offset, 0);
+	WRITE_ONCE(ctrl->read_offset, 0);
+	WRITE_ONCE(ctrl->dep_offset, 0);
+	WRITE_ONCE(ctrl->wrap_mask, pvr_cccb->wrap_mask);
+}
+
+/**
+ * pvr_cccb_init() - Initialise a Client CCB
+ * @pvr_dev: Device pointer.
+ * @pvr_cccb: Pointer to Client CCB structure to initialise.
+ * @size_log2: Log2 size of Client CCB in bytes.
+ * @name: Name of owner of Client CCB. Used for fence context.
+ *
+ * Return:
+ *  * Zero on success, or
+ *  * Any error code returned by pvr_fw_object_create_and_map().
+ */
+int
+pvr_cccb_init(struct pvr_device *pvr_dev, struct pvr_cccb *pvr_cccb,
+	      u32 size_log2, const char *name)
+{
+	size_t size = 1 << size_log2;
+	int err;
+
+	pvr_cccb->size = size;
+	pvr_cccb->write_offset = 0;
+	pvr_cccb->wrap_mask = size - 1;
+
+	/*
+	 * Map CCCB and control structure as uncached, so we don't have to flush
+	 * CPU cache repeatedly when polling for space.
+	 */
+	pvr_cccb->ctrl = pvr_fw_object_create_and_map(pvr_dev, sizeof(*pvr_cccb->ctrl),
+						      PVR_BO_FW_FLAGS_DEVICE_UNCACHED,
+						      cccb_ctrl_init, pvr_cccb,
+						      &pvr_cccb->ctrl_obj);
+	if (IS_ERR(pvr_cccb->ctrl))
+		return PTR_ERR(pvr_cccb->ctrl);
+
+	pvr_cccb->cccb = pvr_fw_object_create_and_map(pvr_dev, size,
+						      PVR_BO_FW_FLAGS_DEVICE_UNCACHED,
+						      NULL, NULL, &pvr_cccb->cccb_obj);
+	if (IS_ERR(pvr_cccb->cccb)) {
+		err = PTR_ERR(pvr_cccb->cccb);
+		goto err_free_ctrl;
+	}
+
+	pvr_fw_object_get_fw_addr(pvr_cccb->ctrl_obj, &pvr_cccb->ctrl_fw_addr);
+	pvr_fw_object_get_fw_addr(pvr_cccb->cccb_obj, &pvr_cccb->cccb_fw_addr);
+
+	return 0;
+
+err_free_ctrl:
+	pvr_fw_object_unmap_and_destroy(pvr_cccb->ctrl_obj);
+
+	return err;
+}
+
+/**
+ * pvr_cccb_fini() - Release Client CCB structure
+ * @pvr_cccb: Client CCB to release.
+ */
+void
+pvr_cccb_fini(struct pvr_cccb *pvr_cccb)
+{
+	pvr_fw_object_unmap_and_destroy(pvr_cccb->cccb_obj);
+	pvr_fw_object_unmap_and_destroy(pvr_cccb->ctrl_obj);
+}
+
+/**
+ * pvr_cccb_cmdseq_fits() - Check if a command sequence fits in the CCCB
+ * @pvr_cccb: Target Client CCB.
+ * @size: Size of the command sequence.
+ *
+ * Check if a command sequence fits in the CCCB we have at hand.
+ *
+ * Return:
+ *  * true if the command sequence fits in the CCCB, or
+ *  * false otherwise.
+ */
+bool pvr_cccb_cmdseq_fits(struct pvr_cccb *pvr_cccb, size_t size)
+{
+	struct rogue_fwif_cccb_ctl *ctrl = pvr_cccb->ctrl;
+	u32 read_offset, remaining;
+	bool fits = false;
+
+	read_offset = READ_ONCE(ctrl->read_offset);
+	remaining = pvr_cccb->size - pvr_cccb->write_offset;
+
+	/* Always ensure we have enough room for a padding command at the end of the CCCB.
+	 * If our command sequence does not fit, reserve the remaining space for a padding
+	 * command.
+	 */
+	if (size + PADDING_COMMAND_SIZE > remaining)
+		size += remaining;
+
+	if (get_ccb_space(pvr_cccb->write_offset, read_offset, pvr_cccb->size) >= size)
+		fits = true;
+
+	return fits;
+}
+
+/**
+ * pvr_cccb_write_command_with_header() - Write a command + command header to a
+ *                                        Client CCB
+ * @pvr_cccb: Target Client CCB.
+ * @cmd_type: Client CCB command type. Must be one of %ROGUE_FWIF_CCB_CMD_TYPE_*.
+ * @cmd_size: Size of command in bytes.
+ * @cmd_data: Pointer to command to write.
+ * @ext_job_ref: External job reference.
+ * @int_job_ref: Internal job reference.
+ *
+ * Caller must make sure there's enough space in CCCB to queue this command. This
+ * can be done by calling pvr_cccb_cmdseq_fits().
+ *
+ * This function is not protected by any lock. The caller must ensure there's
+ * no concurrent caller, which should be guaranteed by the drm_sched model (job
+ * submission is serialized in drm_sched_main()).
+ */
+void
+pvr_cccb_write_command_with_header(struct pvr_cccb *pvr_cccb, u32 cmd_type, u32 cmd_size,
+				   void *cmd_data, u32 ext_job_ref, u32 int_job_ref)
+{
+	u32 sz_with_hdr = pvr_cccb_get_size_of_cmd_with_hdr(cmd_size);
+	struct rogue_fwif_ccb_cmd_header cmd_header = {
+		.cmd_type = cmd_type,
+		.cmd_size = ALIGN(cmd_size, 8),
+		.ext_job_ref = ext_job_ref,
+		.int_job_ref = int_job_ref,
+	};
+	struct rogue_fwif_cccb_ctl *ctrl = pvr_cccb->ctrl;
+	u32 remaining = pvr_cccb->size - pvr_cccb->write_offset;
+	u32 required_size, cccb_space, read_offset;
+
+	/*
+	 * Always ensure we have enough room for a padding command at the end of
+	 * the CCCB.
+	 */
+	if (remaining < sz_with_hdr + PADDING_COMMAND_SIZE) {
+		/*
+		 * Command would need to wrap, so we need to pad the remainder
+		 * of the CCCB.
+		 */
+		required_size = sz_with_hdr + remaining;
+	} else {
+		required_size = sz_with_hdr;
+	}
+
+	read_offset = READ_ONCE(ctrl->read_offset);
+	cccb_space = get_ccb_space(pvr_cccb->write_offset, read_offset, pvr_cccb->size);
+	if (WARN_ON(cccb_space < required_size))
+		return;
+
+	if (required_size != sz_with_hdr) {
+		/* Add padding command */
+		struct rogue_fwif_ccb_cmd_header pad_cmd = {
+			.cmd_type = ROGUE_FWIF_CCB_CMD_TYPE_PADDING,
+			.cmd_size = remaining - sizeof(pad_cmd),
+		};
+
+		memcpy(&pvr_cccb->cccb[pvr_cccb->write_offset], &pad_cmd, sizeof(pad_cmd));
+		pvr_cccb->write_offset = 0;
+	}
+
+	memcpy(&pvr_cccb->cccb[pvr_cccb->write_offset], &cmd_header, sizeof(cmd_header));
+	memcpy(&pvr_cccb->cccb[pvr_cccb->write_offset + sizeof(cmd_header)], cmd_data, cmd_size);
+	pvr_cccb->write_offset += sz_with_hdr;
+}
+
+static void fill_cmd_kick_data(struct pvr_cccb *cccb, u32 ctx_fw_addr,
+			       struct pvr_hwrt_data *hwrt,
+			       struct rogue_fwif_kccb_cmd_kick_data *k)
+{
+	k->context_fw_addr = ctx_fw_addr;
+	k->client_woff_update = cccb->write_offset;
+	k->client_wrap_mask_update = cccb->wrap_mask;
+
+	if (hwrt) {
+		u32 cleanup_state_offset = offsetof(struct rogue_fwif_hwrtdata, cleanup_state);
+
+		pvr_fw_object_get_fw_addr_offset(hwrt->fw_obj, cleanup_state_offset,
+						 &k->cleanup_ctl_fw_addr[k->num_cleanup_ctl++]);
+	}
+}
+
+/**
+ * pvr_cccb_send_kccb_kick: Send KCCB kick to trigger command processing
+ * @pvr_dev: Device pointer.
+ * @pvr_cccb: Pointer to CCCB to process.
+ * @cctx_fw_addr: FW virtual address for context owning this Client CCB.
+ * @hwrt: HWRT data set associated with this kick. May be %NULL.
+ *
+ * You must call pvr_kccb_reserve_slot() and wait for the returned fence to
+ * signal (if this function didn't return NULL) before calling
+ * pvr_cccb_send_kccb_kick().
+ */
+void
+pvr_cccb_send_kccb_kick(struct pvr_device *pvr_dev,
+			struct pvr_cccb *pvr_cccb, u32 cctx_fw_addr,
+			struct pvr_hwrt_data *hwrt)
+{
+	struct rogue_fwif_kccb_cmd cmd_kick = {
+		.cmd_type = ROGUE_FWIF_KCCB_CMD_KICK,
+	};
+
+	fill_cmd_kick_data(pvr_cccb, cctx_fw_addr, hwrt, &cmd_kick.cmd_data.cmd_kick_data);
+
+	/* Make sure the writes to the CCCB are flushed before sending the KICK. */
+	wmb();
+
+	pvr_kccb_send_cmd_reserved_powered(pvr_dev, &cmd_kick, NULL);
+}
+
+void
+pvr_cccb_send_kccb_combined_kick(struct pvr_device *pvr_dev,
+				 struct pvr_cccb *geom_cccb,
+				 struct pvr_cccb *frag_cccb,
+				 u32 geom_ctx_fw_addr,
+				 u32 frag_ctx_fw_addr,
+				 struct pvr_hwrt_data *hwrt,
+				 bool frag_is_pr)
+{
+	struct rogue_fwif_kccb_cmd cmd_kick = {
+		.cmd_type = ROGUE_FWIF_KCCB_CMD_COMBINED_GEOM_FRAG_KICK,
+	};
+
+	fill_cmd_kick_data(geom_cccb, geom_ctx_fw_addr, hwrt,
+			   &cmd_kick.cmd_data.combined_geom_frag_cmd_kick_data.geom_cmd_kick_data);
+
+	/* If this is a partial-render job, we don't attach resources to cleanup-ctl array,
+	 * because the resources are already retained by the geometry job.
+	 */
+	fill_cmd_kick_data(frag_cccb, frag_ctx_fw_addr, frag_is_pr ? NULL : hwrt,
+			   &cmd_kick.cmd_data.combined_geom_frag_cmd_kick_data.frag_cmd_kick_data);
+
+	/* Make sure the writes to the CCCB are flushed before sending the KICK. */
+	wmb();
+
+	pvr_kccb_send_cmd_reserved_powered(pvr_dev, &cmd_kick, NULL);
+}

drivers/gpu/drm/imagination/pvr_cccb.h

@@ -0,0 +1,109 @@
+/* SPDX-License-Identifier: GPL-2.0-only OR MIT */
+/* Copyright (c) 2023 Imagination Technologies Ltd. */
+
+#ifndef PVR_CCCB_H
+#define PVR_CCCB_H
+
+#include "pvr_rogue_fwif.h"
+#include "pvr_rogue_fwif_shared.h"
+
+#include <linux/mutex.h>
+#include <linux/types.h>
+
+#define PADDING_COMMAND_SIZE sizeof(struct rogue_fwif_ccb_cmd_header)
+
+/* Forward declaration from pvr_device.h. */
+struct pvr_device;
+
+/* Forward declaration from pvr_gem.h. */
+struct pvr_fw_object;
+
+/* Forward declaration from pvr_hwrt.h. */
+struct pvr_hwrt_data;
+
+struct pvr_cccb {
+	/** @ctrl_obj: FW object representing CCCB control structure. */
+	struct pvr_fw_object *ctrl_obj;
+
+	/** @ccb_obj: FW object representing CCCB. */
+	struct pvr_fw_object *cccb_obj;
+
+	/**
+	 * @ctrl: Kernel mapping of CCCB control structure. @lock must be held
+	 *        when accessing.
+	 */
+	struct rogue_fwif_cccb_ctl *ctrl;
+
+	/** @cccb: Kernel mapping of CCCB. @lock must be held when accessing.*/
+	u8 *cccb;
+
+	/** @ctrl_fw_addr: FW virtual address of CCCB control structure. */
+	u32 ctrl_fw_addr;
+	/** @ccb_fw_addr: FW virtual address of CCCB. */
+	u32 cccb_fw_addr;
+
+	/** @size: Size of CCCB in bytes. */
+	size_t size;
+
+	/** @write_offset: CCCB write offset. */
+	u32 write_offset;
+
+	/** @wrap_mask: CCCB wrap mask. */
+	u32 wrap_mask;
+};
+
+int pvr_cccb_init(struct pvr_device *pvr_dev, struct pvr_cccb *cccb,
+		  u32 size_log2, const char *name);
+void pvr_cccb_fini(struct pvr_cccb *cccb);
+
+void pvr_cccb_write_command_with_header(struct pvr_cccb *pvr_cccb,
+					u32 cmd_type, u32 cmd_size, void *cmd_data,
+					u32 ext_job_ref, u32 int_job_ref);
+void pvr_cccb_send_kccb_kick(struct pvr_device *pvr_dev,
+			     struct pvr_cccb *pvr_cccb, u32 cctx_fw_addr,
+			     struct pvr_hwrt_data *hwrt);
+void pvr_cccb_send_kccb_combined_kick(struct pvr_device *pvr_dev,
+				      struct pvr_cccb *geom_cccb,
+				      struct pvr_cccb *frag_cccb,
+				      u32 geom_ctx_fw_addr,
+				      u32 frag_ctx_fw_addr,
+				      struct pvr_hwrt_data *hwrt,
+				      bool frag_is_pr);
+bool pvr_cccb_cmdseq_fits(struct pvr_cccb *pvr_cccb, size_t size);
+
+/**
+ * pvr_cccb_get_size_of_cmd_with_hdr() - Get the size of a command and its header.
+ * @cmd_size: Command size.
+ *
+ * Returns the size of the command and its header.
+ */
+static __always_inline u32
+pvr_cccb_get_size_of_cmd_with_hdr(u32 cmd_size)
+{
+	WARN_ON(!IS_ALIGNED(cmd_size, 8));
+	return sizeof(struct rogue_fwif_ccb_cmd_header) + ALIGN(cmd_size, 8);
+}
+
+/**
+ * pvr_cccb_cmdseq_can_fit() - Check if a command sequence can fit in the CCCB.
+ * @size: Command sequence size.
+ *
+ * Returns:
+ *  * true it the CCCB is big enough to contain a command sequence, or
+ *  * false otherwise.
+ */
+static __always_inline bool
+pvr_cccb_cmdseq_can_fit(struct pvr_cccb *pvr_cccb, size_t size)
+{
+	/* We divide the capacity by two to simplify our CCCB fencing logic:
+	 * we want to be sure that, no matter what we had queued before, we
+	 * are able to either queue our command sequence at the end or add a
+	 * padding command and queue the command sequence at the beginning
+	 * of the CCCB. If the command sequence size is bigger than half the
+	 * CCCB capacity, we'd have to queue the padding command and make sure
+	 * the FW is done processing it before queueing our command sequence.
+	 */
+	return size + PADDING_COMMAND_SIZE <= pvr_cccb->size / 2;
+}
+
+#endif /* PVR_CCCB_H */