[v2,06/15] media: intel/ipu6: add syscom interfaces between firmware and driver

diff --git a/drivers/media/pci/intel/ipu6/ipu6-fw-com.c b/drivers/media/pci/intel/ipu6/ipu6-fw-com.c
new file mode 100644
index 000000000000..a162cc657234
--- /dev/null
+++ b/drivers/media/pci/intel/ipu6/ipu6-fw-com.c
@@ -0,0 +1,411 @@ 
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2013 - 2023 Intel Corporation
+ */
+
+#include "ipu6.h"
+#include "ipu6-bus.h"
+#include "ipu6-fw-com.h"
+
+/*
+ * FWCOM layer is a shared resource between FW and driver. It consist
+ * of token queues to both send and receive directions. Queue is simply
+ * an array of structures with read and write indexes to the queue.
+ * There are 1...n queues to both directions. Queues locates in
+ * system RAM and are mapped to ISP MMU so that both CPU and ISP can
+ * see the same buffer. Indexes are located in ISP DMEM so that FW code
+ * can poll those with very low latency and cost. CPU access to indexes is
+ * more costly but that happens only at message sending time and
+ * interrupt triggered message handling. CPU doesn't need to poll indexes.
+ * wr_reg / rd_reg are offsets to those dmem location. They are not
+ * the indexes itself.
+ */
+
+/* Shared structure between driver and FW - do not modify */
+struct ipu6_fw_sys_queue {
+	u64 host_address;
+	u32 vied_address;
+	u32 size;
+	u32 token_size;
+	u32 wr_reg;	/* reg number in subsystem's regmem */
+	u32 rd_reg;
+	u32 _align;
+} __packed;
+
+struct ipu6_fw_sys_queue_res {
+	u64 host_address;
+	u32 vied_address;
+	u32 reg;
+} __packed;
+
+enum syscom_state {
+	/* Program load or explicit host setting should init to this */
+	SYSCOM_STATE_UNINIT = 0x57A7E000,
+	/* SP Syscom sets this when it is ready for use */
+	SYSCOM_STATE_READY = 0x57A7E001,
+	/* SP Syscom sets this when no more syscom accesses will happen */
+	SYSCOM_STATE_INACTIVE = 0x57A7E002
+};
+
+enum syscom_cmd {
+	/* Program load or explicit host setting should init to this */
+	SYSCOM_COMMAND_UNINIT = 0x57A7F000,
+	/* Host Syscom requests syscom to become inactive */
+	SYSCOM_COMMAND_INACTIVE = 0x57A7F001
+};
+
+/* firmware config: data that sent from the host to SP via DDR */
+/* Cell copies data into a context */
+
+struct ipu6_fw_syscom_config {
+	u32 firmware_address;
+
+	u32 num_input_queues;
+	u32 num_output_queues;
+
+	/* ISP pointers to an array of ipu6_fw_sys_queue structures */
+	u32 input_queue;
+	u32 output_queue;
+
+	/* ISYS / PSYS private data */
+	u32 specific_addr;
+	u32 specific_size;
+};
+
+struct ipu6_fw_com_context {
+	struct ipu6_bus_device *adev;
+	void __iomem *dmem_addr;
+	int (*cell_ready)(struct ipu6_bus_device *adev);
+	void (*cell_start)(struct ipu6_bus_device *adev);
+
+	void *dma_buffer;
+	dma_addr_t dma_addr;
+	unsigned int dma_size;
+	unsigned long attrs;
+
+	struct ipu6_fw_sys_queue *input_queue;	/* array of host to SP queues */
+	struct ipu6_fw_sys_queue *output_queue;	/* array of SP to host */
+
+	u32 config_vied_addr;
+
+	unsigned int buttress_boot_offset;
+	void __iomem *base_addr;
+};
+
+#define FW_COM_WR_REG 0
+#define FW_COM_RD_REG 4
+
+#define REGMEM_OFFSET 0
+#define TUNIT_MAGIC_PATTERN 0x5a5a5a5a
+
+enum regmem_id {
+	/* pass pkg_dir address to SPC in non-secure mode */
+	PKG_DIR_ADDR_REG = 0,
+	/* Tunit CFG blob for secure - provided by host.*/
+	TUNIT_CFG_DWR_REG = 1,
+	/* syscom commands - modified by the host */
+	SYSCOM_COMMAND_REG = 2,
+	/* Store interrupt status - updated by SP */
+	SYSCOM_IRQ_REG = 3,
+	/* first syscom queue pointer register */
+	SYSCOM_QPR_BASE_REG = 4
+};
+
+enum message_direction {
+	DIR_RECV = 0,
+	DIR_SEND
+};
+
+#define BUTTRESS_FW_BOOT_PARAMS_0 0x4000
+#define BUTTRESS_FW_BOOT_PARAM_REG(base, offset, id)			\
+	((base) + BUTTRESS_FW_BOOT_PARAMS_0 + ((offset) + (id)) * 4)
+
+enum buttress_syscom_id {
+	/* pass syscom configuration to SPC */
+	SYSCOM_CONFIG_ID		= 0,
+	/* syscom state - modified by SP */
+	SYSCOM_STATE_ID			= 1,
+	/* syscom vtl0 addr mask */
+	SYSCOM_VTL0_ADDR_MASK_ID	= 2,
+	SYSCOM_ID_MAX
+};
+
+static void ipu6_sys_queue_init(struct ipu6_fw_sys_queue *q, unsigned int size,
+				unsigned int token_size,
+				struct ipu6_fw_sys_queue_res *res)
+{
+	unsigned int buf_size = (size + 1) * token_size;
+
+	q->size = size + 1;
+	q->token_size = token_size;
+
+	/* acquire the shared buffer space */
+	q->host_address = res->host_address;
+	res->host_address += buf_size;
+	q->vied_address = res->vied_address;
+	res->vied_address += buf_size;
+
+	/* acquire the shared read and writer pointers */
+	q->wr_reg = res->reg;
+	res->reg++;
+	q->rd_reg = res->reg;
+	res->reg++;
+}
+
+void *ipu6_fw_com_prepare(struct ipu6_fw_com_cfg *cfg,
+			  struct ipu6_bus_device *adev, void __iomem *base)
+{
+	size_t conf_size, inq_size, outq_size, specific_size;
+	struct ipu6_fw_syscom_config *config_host_addr;
+	unsigned int sizeinput = 0, sizeoutput = 0;
+	struct ipu6_fw_sys_queue_res res;
+	struct ipu6_fw_com_context *ctx;
+	struct device *dev = &adev->auxdev.dev;
+	size_t sizeall, offset;
+	unsigned long attrs = 0;
+	void *specific_host_addr;
+	unsigned int i;
+
+	if (!cfg || !cfg->cell_start || !cfg->cell_ready)
+		return NULL;
+
+	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+	if (!ctx)
+		return NULL;
+	ctx->dmem_addr = base + cfg->dmem_addr + REGMEM_OFFSET;
+	ctx->adev = adev;
+	ctx->cell_start = cfg->cell_start;
+	ctx->cell_ready = cfg->cell_ready;
+	ctx->buttress_boot_offset = cfg->buttress_boot_offset;
+	ctx->base_addr  = base;
+
+	/*
+	 * Allocate DMA mapped memory. Allocate one big chunk.
+	 */
+	/* Base cfg for FW */
+	conf_size = roundup(sizeof(struct ipu6_fw_syscom_config), 8);
+	/* Descriptions of the queues */
+	inq_size = size_mul(cfg->num_input_queues,
+			    sizeof(struct ipu6_fw_sys_queue));
+	outq_size = size_mul(cfg->num_output_queues,
+			     sizeof(struct ipu6_fw_sys_queue));
+	/* FW specific information structure */
+	specific_size = roundup(cfg->specific_size, 8);
+
+	sizeall = conf_size + inq_size + outq_size + specific_size;
+
+	for (i = 0; i < cfg->num_input_queues; i++)
+		sizeinput += size_mul(cfg->input[i].queue_size + 1,
+				      cfg->input[i].token_size);
+
+	for (i = 0; i < cfg->num_output_queues; i++)
+		sizeoutput += size_mul(cfg->output[i].queue_size + 1,
+				       cfg->output[i].token_size);
+
+	sizeall += sizeinput + sizeoutput;
+
+	ctx->dma_buffer = dma_alloc_attrs(dev, sizeall, &ctx->dma_addr,
+					  GFP_KERNEL, attrs);
+	ctx->attrs = attrs;
+	if (!ctx->dma_buffer) {
+		dev_err(dev, "failed to allocate dma memory\n");
+		kfree(ctx);
+		return NULL;
+	}
+
+	ctx->dma_size = sizeall;
+
+	config_host_addr = ctx->dma_buffer;
+	ctx->config_vied_addr = ctx->dma_addr;
+
+	offset = conf_size;
+	ctx->input_queue = ctx->dma_buffer + offset;
+	config_host_addr->input_queue = ctx->dma_addr + offset;
+	config_host_addr->num_input_queues = cfg->num_input_queues;
+
+	offset += inq_size;
+	ctx->output_queue = ctx->dma_buffer + offset;
+	config_host_addr->output_queue = ctx->dma_addr + offset;
+	config_host_addr->num_output_queues = cfg->num_output_queues;
+
+	/* copy firmware specific data */
+	offset += outq_size;
+	specific_host_addr = ctx->dma_buffer + offset;
+	config_host_addr->specific_addr = ctx->dma_addr + offset;
+	config_host_addr->specific_size = cfg->specific_size;
+	if (cfg->specific_addr && cfg->specific_size)
+		memcpy(specific_host_addr, cfg->specific_addr,
+		       cfg->specific_size);
+
+	/* initialize input queues */
+	offset += specific_size;
+	res.reg = SYSCOM_QPR_BASE_REG;
+	res.host_address = (u64)(ctx->dma_buffer + offset);
+	res.vied_address = ctx->dma_addr + offset;
+	for (i = 0; i < cfg->num_input_queues; i++)
+		ipu6_sys_queue_init(ctx->input_queue + i,
+				    cfg->input[i].queue_size,
+				    cfg->input[i].token_size, &res);
+
+	/* initialize output queues */
+	offset += sizeinput;
+	res.host_address = (u64)(ctx->dma_buffer + offset);
+	res.vied_address = ctx->dma_addr + offset;
+	for (i = 0; i < cfg->num_output_queues; i++) {
+		ipu6_sys_queue_init(ctx->output_queue + i,
+				    cfg->output[i].queue_size,
+				    cfg->output[i].token_size, &res);
+	}
+
+	return ctx;
+}
+EXPORT_SYMBOL_NS_GPL(ipu6_fw_com_prepare, INTEL_IPU6);
+
+int ipu6_fw_com_open(struct ipu6_fw_com_context *ctx)
+{
+	/* write magic pattern to disable the tunit trace */
+	writel(TUNIT_MAGIC_PATTERN, ctx->dmem_addr + TUNIT_CFG_DWR_REG * 4);
+	/* Check if SP is in valid state */
+	if (!ctx->cell_ready(ctx->adev))
+		return -EIO;
+
+	/* store syscom uninitialized command */
+	writel(SYSCOM_COMMAND_UNINIT, ctx->dmem_addr + SYSCOM_COMMAND_REG * 4);
+
+	/* store syscom uninitialized state */
+	writel(SYSCOM_STATE_UNINIT,
+	       BUTTRESS_FW_BOOT_PARAM_REG(ctx->base_addr,
+					  ctx->buttress_boot_offset,
+					  SYSCOM_STATE_ID));
+
+	/* store firmware configuration address */
+	writel(ctx->config_vied_addr,
+	       BUTTRESS_FW_BOOT_PARAM_REG(ctx->base_addr,
+					  ctx->buttress_boot_offset,
+					  SYSCOM_CONFIG_ID));
+	ctx->cell_start(ctx->adev);
+
+	return 0;
+}
+EXPORT_SYMBOL_NS_GPL(ipu6_fw_com_open, INTEL_IPU6);
+
+int ipu6_fw_com_close(struct ipu6_fw_com_context *ctx)
+{
+	int state;
+
+	state = readl(BUTTRESS_FW_BOOT_PARAM_REG(ctx->base_addr,
+						 ctx->buttress_boot_offset,
+						 SYSCOM_STATE_ID));
+	if (state != SYSCOM_STATE_READY)
+		return -EBUSY;
+
+	/* set close request flag */
+	writel(SYSCOM_COMMAND_INACTIVE, ctx->dmem_addr +
+	       SYSCOM_COMMAND_REG * 4);
+
+	return 0;
+}
+EXPORT_SYMBOL_NS_GPL(ipu6_fw_com_close, INTEL_IPU6);
+
+int ipu6_fw_com_release(struct ipu6_fw_com_context *ctx, unsigned int force)
+{
+	/* check if release is forced, an verify cell state if it is not */
+	if (!force && !ctx->cell_ready(ctx->adev))
+		return -EBUSY;
+
+	dma_free_attrs(&ctx->adev->auxdev.dev, ctx->dma_size,
+		       ctx->dma_buffer, ctx->dma_addr, ctx->attrs);
+	kfree(ctx);
+	return 0;
+}
+EXPORT_SYMBOL_NS_GPL(ipu6_fw_com_release, INTEL_IPU6);
+
+bool ipu6_fw_com_ready(struct ipu6_fw_com_context *ctx)
+{
+	int state;
+
+	state = readl(BUTTRESS_FW_BOOT_PARAM_REG(ctx->base_addr,
+						 ctx->buttress_boot_offset,
+						 SYSCOM_STATE_ID));
+
+	return state == SYSCOM_STATE_READY;
+}
+EXPORT_SYMBOL_NS_GPL(ipu6_fw_com_ready, INTEL_IPU6);
+
+void *ipu6_send_get_token(struct ipu6_fw_com_context *ctx, int q_nbr)
+{
+	struct ipu6_fw_sys_queue *q = &ctx->input_queue[q_nbr];
+	void __iomem *q_dmem = ctx->dmem_addr + q->wr_reg * 4;
+	unsigned int wr, rd;
+	unsigned int packets;
+	unsigned int index;
+
+	wr = readl(q_dmem + FW_COM_WR_REG);
+	rd = readl(q_dmem + FW_COM_RD_REG);
+
+	if (WARN_ON_ONCE(wr >= q->size || rd >= q->size))
+		return NULL;
+
+	if (wr < rd)
+		packets = rd - wr - 1;
+	else
+		packets = q->size - (wr - rd + 1);
+
+	if (!packets)
+		return NULL;
+
+	index = readl(q_dmem + FW_COM_WR_REG);
+
+	return (void *)(q->host_address + index * q->token_size);
+}
+EXPORT_SYMBOL_NS_GPL(ipu6_send_get_token, INTEL_IPU6);
+
+void ipu6_send_put_token(struct ipu6_fw_com_context *ctx, int q_nbr)
+{
+	struct ipu6_fw_sys_queue *q = &ctx->input_queue[q_nbr];
+	void __iomem *q_dmem = ctx->dmem_addr + q->wr_reg * 4;
+	unsigned int wr = readl(q_dmem + FW_COM_WR_REG) + 1;
+
+	if (wr >= q->size)
+		wr = 0;
+
+	writel(wr, q_dmem + FW_COM_WR_REG);
+}
+EXPORT_SYMBOL_NS_GPL(ipu6_send_put_token, INTEL_IPU6);
+
+void *ipu6_recv_get_token(struct ipu6_fw_com_context *ctx, int q_nbr)
+{
+	struct ipu6_fw_sys_queue *q = &ctx->output_queue[q_nbr];
+	void __iomem *q_dmem = ctx->dmem_addr + q->wr_reg * 4;
+	unsigned int wr, rd;
+	unsigned int packets;
+
+	wr = readl(q_dmem + FW_COM_WR_REG);
+	rd = readl(q_dmem + FW_COM_RD_REG);
+
+	if (WARN_ON_ONCE(wr >= q->size || rd >= q->size))
+		return NULL;
+
+	if (wr < rd)
+		wr += q->size;
+
+	packets = wr - rd;
+	if (!packets)
+		return NULL;
+
+	return (void *)(q->host_address + rd * q->token_size);
+}
+EXPORT_SYMBOL_NS_GPL(ipu6_recv_get_token, INTEL_IPU6);
+
+void ipu6_recv_put_token(struct ipu6_fw_com_context *ctx, int q_nbr)
+{
+	struct ipu6_fw_sys_queue *q = &ctx->output_queue[q_nbr];
+	void __iomem *q_dmem = ctx->dmem_addr + q->wr_reg * 4;
+	unsigned int rd = readl(q_dmem + FW_COM_RD_REG) + 1;
+
+	if (rd >= q->size)
+		rd = 0;
+
+	writel(rd, q_dmem + FW_COM_RD_REG);
+}
+EXPORT_SYMBOL_NS_GPL(ipu6_recv_put_token, INTEL_IPU6);
diff --git a/drivers/media/pci/intel/ipu6/ipu6-fw-com.h b/drivers/media/pci/intel/ipu6/ipu6-fw-com.h
new file mode 100644
index 000000000000..660c406b3ac9
--- /dev/null
+++ b/drivers/media/pci/intel/ipu6/ipu6-fw-com.h
@@ -0,0 +1,47 @@ 
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Copyright (C) 2013 - 2023 Intel Corporation */
+
+#ifndef IPU6_FW_COM_H
+#define IPU6_FW_COM_H
+
+struct ipu6_fw_com_context;
+struct ipu6_bus_device;
+
+struct ipu6_fw_syscom_queue_config {
+	unsigned int queue_size;	/* tokens per queue */
+	unsigned int token_size;	/* bytes per token */
+};
+
+#define SYSCOM_BUTTRESS_FW_PARAMS_ISYS_OFFSET	0
+
+struct ipu6_fw_com_cfg {
+	unsigned int num_input_queues;
+	unsigned int num_output_queues;
+	struct ipu6_fw_syscom_queue_config *input;
+	struct ipu6_fw_syscom_queue_config *output;
+
+	unsigned int dmem_addr;
+
+	/* firmware-specific configuration data */
+	void *specific_addr;
+	unsigned int specific_size;
+	int (*cell_ready)(struct ipu6_bus_device *adev);
+	void (*cell_start)(struct ipu6_bus_device *adev);
+
+	unsigned int buttress_boot_offset;
+};
+
+void *ipu6_fw_com_prepare(struct ipu6_fw_com_cfg *cfg,
+			  struct ipu6_bus_device *adev, void __iomem *base);
+
+int ipu6_fw_com_open(struct ipu6_fw_com_context *ctx);
+bool ipu6_fw_com_ready(struct ipu6_fw_com_context *ctx);
+int ipu6_fw_com_close(struct ipu6_fw_com_context *ctx);
+int ipu6_fw_com_release(struct ipu6_fw_com_context *ctx, unsigned int force);
+
+void *ipu6_recv_get_token(struct ipu6_fw_com_context *ctx, int q_nbr);
+void ipu6_recv_put_token(struct ipu6_fw_com_context *ctx, int q_nbr);
+void *ipu6_send_get_token(struct ipu6_fw_com_context *ctx, int q_nbr);
+void ipu6_send_put_token(struct ipu6_fw_com_context *ctx, int q_nbr);
+
+#endif