soc: ti: k3: add navss ringacc driver

The Ring Accelerator (RINGACC or RA) provides hardware acceleration to
enable straightforward passing of work between a producer and a consumer.
There is one RINGACC module per NAVSS on TI AM65x SoCs.

The RINGACC converts constant-address read and write accesses to equivalent
read or write accesses to a circular data structure in memory. The RINGACC
eliminates the need for each DMA controller which needs to access ring
elements from having to know the current state of the ring (base address,
current offset). The DMA controller performs a read or write access to a
specific address range (which maps to the source interface on the RINGACC)
and the RINGACC replaces the address for the transaction with a new address
which corresponds to the head or tail element of the ring (head for reads,
tail for writes). Since the RINGACC maintains the state, multiple DMA
controllers or channels are allowed to coherently share the same rings as
applicable. The RINGACC is able to place data which is destined towards
software into cached memory directly.

Supported ring modes:
- Ring Mode
- Messaging Mode
- Credentials Mode
- Queue Manager Mode

TI-SCI integration:

Texas Instrument's System Control Interface (TI-SCI) Message Protocol now
has control over Ringacc module resources management (RM) and Rings
configuration.

The corresponding support of TI-SCI Ringacc module RM protocol
introduced as option through DT parameters:
- ti,sci: phandle on TI-SCI firmware controller DT node
- ti,sci-dev-id: TI-SCI device identifier as per TI-SCI firmware spec

if both parameters present - Ringacc driver will configure/free/reset Rings
using TI-SCI Message Ringacc RM Protocol.

The Ringacc driver manages Rings allocation by itself now and requests
TI-SCI firmware to allocate and configure specific Rings only. It's done
this way because, Linux driver implements two stage Rings allocation and
configuration (allocate ring and configure ring) while TI-SCI Message
Protocol supports only one combined operation (allocate+configure).

Signed-off-by: Grygorii Strashko <[e-mail]>
Signed-off-by: Peter Ujfalusi <[e-mail]>
Reviewed-by: Tero Kristo <[e-mail]>
Tested-by: Keerthy <[e-mail]>
Signed-off-by: Santosh Shilimkar <[e-mail]>

drivers/soc/ti/Kconfig

···
 	  called ti_sci_pm_domains. Note this is needed early in boot before
 	  rootfs may be available.
 
+config TI_K3_RINGACC
+	bool "K3 Ring accelerator Sub System"
+	depends on ARCH_K3 || COMPILE_TEST
+	depends on TI_SCI_INTA_IRQCHIP
+	help
+	  Say y here to support the K3 Ring accelerator module.
+	  The Ring Accelerator (RINGACC or RA)  provides hardware acceleration
+	  to enable straightforward passing of work between a producer
+	  and a consumer. There is one RINGACC module per NAVSS on TI AM65x SoCs
+	  If unsure, say N.
+
 endif # SOC_TI
 
 config TI_SCI_INTA_MSI_DOMAIN

drivers/soc/ti/Makefile

···
 obj-$(CONFIG_WKUP_M3_IPC)		+= wkup_m3_ipc.o
 obj-$(CONFIG_TI_SCI_PM_DOMAINS)		+= ti_sci_pm_domains.o
 obj-$(CONFIG_TI_SCI_INTA_MSI_DOMAIN)	+= ti_sci_inta_msi.o
+obj-$(CONFIG_TI_K3_RINGACC)		+= k3-ringacc.o

drivers/soc/ti/k3-ringacc.c

···
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * TI K3 NAVSS Ring Accelerator subsystem driver
+ *
+ * Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com
+ */
+
+#include <linux/dma-mapping.h>
+#include <linux/io.h>
+#include <linux/init.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/soc/ti/k3-ringacc.h>
+#include <linux/soc/ti/ti_sci_protocol.h>
+#include <linux/soc/ti/ti_sci_inta_msi.h>
+#include <linux/of_irq.h>
+#include <linux/irqdomain.h>
+
+static LIST_HEAD(k3_ringacc_list);
+static DEFINE_MUTEX(k3_ringacc_list_lock);
+
+#define K3_RINGACC_CFG_RING_SIZE_ELCNT_MASK		GENMASK(19, 0)
+
+/**
+ * struct k3_ring_rt_regs - The RA realtime Control/Status Registers region
+ *
+ * @resv_16: Reserved
+ * @db: Ring Doorbell Register
+ * @resv_4: Reserved
+ * @occ: Ring Occupancy Register
+ * @indx: Ring Current Index Register
+ * @hwocc: Ring Hardware Occupancy Register
+ * @hwindx: Ring Hardware Current Index Register
+ */
+struct k3_ring_rt_regs {
+	u32	resv_16[4];
+	u32	db;
+	u32	resv_4[1];
+	u32	occ;
+	u32	indx;
+	u32	hwocc;
+	u32	hwindx;
+};
+
+#define K3_RINGACC_RT_REGS_STEP	0x1000
+
+/**
+ * struct k3_ring_fifo_regs - The Ring Accelerator Queues Registers region
+ *
+ * @head_data: Ring Head Entry Data Registers
+ * @tail_data: Ring Tail Entry Data Registers
+ * @peek_head_data: Ring Peek Head Entry Data Regs
+ * @peek_tail_data: Ring Peek Tail Entry Data Regs
+ */
+struct k3_ring_fifo_regs {
+	u32	head_data[128];
+	u32	tail_data[128];
+	u32	peek_head_data[128];
+	u32	peek_tail_data[128];
+};
+
+/**
+ * struct k3_ringacc_proxy_gcfg_regs - RA Proxy Global Config MMIO Region
+ *
+ * @revision: Revision Register
+ * @config: Config Register
+ */
+struct k3_ringacc_proxy_gcfg_regs {
+	u32	revision;
+	u32	config;
+};
+
+#define K3_RINGACC_PROXY_CFG_THREADS_MASK		GENMASK(15, 0)
+
+/**
+ * struct k3_ringacc_proxy_target_regs - Proxy Datapath MMIO Region
+ *
+ * @control: Proxy Control Register
+ * @status: Proxy Status Register
+ * @resv_512: Reserved
+ * @data: Proxy Data Register
+ */
+struct k3_ringacc_proxy_target_regs {
+	u32	control;
+	u32	status;
+	u8	resv_512[504];
+	u32	data[128];
+};
+
+#define K3_RINGACC_PROXY_TARGET_STEP	0x1000
+#define K3_RINGACC_PROXY_NOT_USED	(-1)
+
+enum k3_ringacc_proxy_access_mode {
+	PROXY_ACCESS_MODE_HEAD = 0,
+	PROXY_ACCESS_MODE_TAIL = 1,
+	PROXY_ACCESS_MODE_PEEK_HEAD = 2,
+	PROXY_ACCESS_MODE_PEEK_TAIL = 3,
+};
+
+#define K3_RINGACC_FIFO_WINDOW_SIZE_BYTES  (512U)
+#define K3_RINGACC_FIFO_REGS_STEP	0x1000
+#define K3_RINGACC_MAX_DB_RING_CNT    (127U)
+
+struct k3_ring_ops {
+	int (*push_tail)(struct k3_ring *ring, void *elm);
+	int (*push_head)(struct k3_ring *ring, void *elm);
+	int (*pop_tail)(struct k3_ring *ring, void *elm);
+	int (*pop_head)(struct k3_ring *ring, void *elm);
+};
+
+/**
+ * struct k3_ring - RA Ring descriptor
+ *
+ * @rt: Ring control/status registers
+ * @fifos: Ring queues registers
+ * @proxy: Ring Proxy Datapath registers
+ * @ring_mem_dma: Ring buffer dma address
+ * @ring_mem_virt: Ring buffer virt address
+ * @ops: Ring operations
+ * @size: Ring size in elements
+ * @elm_size: Size of the ring element
+ * @mode: Ring mode
+ * @flags: flags
+ * @free: Number of free elements
+ * @occ: Ring occupancy
+ * @windex: Write index (only for @K3_RINGACC_RING_MODE_RING)
+ * @rindex: Read index (only for @K3_RINGACC_RING_MODE_RING)
+ * @ring_id: Ring Id
+ * @parent: Pointer on struct @k3_ringacc
+ * @use_count: Use count for shared rings
+ * @proxy_id: RA Ring Proxy Id (only if @K3_RINGACC_RING_USE_PROXY)
+ */
+struct k3_ring {
+	struct k3_ring_rt_regs __iomem *rt;
+	struct k3_ring_fifo_regs __iomem *fifos;
+	struct k3_ringacc_proxy_target_regs  __iomem *proxy;
+	dma_addr_t	ring_mem_dma;
+	void		*ring_mem_virt;
+	struct k3_ring_ops *ops;
+	u32		size;
+	enum k3_ring_size elm_size;
+	enum k3_ring_mode mode;
+	u32		flags;
+#define K3_RING_FLAG_BUSY	BIT(1)
+#define K3_RING_FLAG_SHARED	BIT(2)
+	u32		free;
+	u32		occ;
+	u32		windex;
+	u32		rindex;
+	u32		ring_id;
+	struct k3_ringacc	*parent;
+	u32		use_count;
+	int		proxy_id;
+};
+
+/**
+ * struct k3_ringacc - Rings accelerator descriptor
+ *
+ * @dev: pointer on RA device
+ * @proxy_gcfg: RA proxy global config registers
+ * @proxy_target_base: RA proxy datapath region
+ * @num_rings: number of ring in RA
+ * @rings_inuse: bitfield for ring usage tracking
+ * @rm_gp_range: general purpose rings range from tisci
+ * @dma_ring_reset_quirk: DMA reset w/a enable
+ * @num_proxies: number of RA proxies
+ * @proxy_inuse: bitfield for proxy usage tracking
+ * @rings: array of rings descriptors (struct @k3_ring)
+ * @list: list of RAs in the system
+ * @req_lock: protect rings allocation
+ * @tisci: pointer ti-sci handle
+ * @tisci_ring_ops: ti-sci rings ops
+ * @tisci_dev_id: ti-sci device id
+ */
+struct k3_ringacc {
+	struct device *dev;
+	struct k3_ringacc_proxy_gcfg_regs __iomem *proxy_gcfg;
+	void __iomem *proxy_target_base;
+	u32 num_rings; /* number of rings in Ringacc module */
+	unsigned long *rings_inuse;
+	struct ti_sci_resource *rm_gp_range;
+
+	bool dma_ring_reset_quirk;
+	u32 num_proxies;
+	unsigned long *proxy_inuse;
+
+	struct k3_ring *rings;
+	struct list_head list;
+	struct mutex req_lock; /* protect rings allocation */
+
+	const struct ti_sci_handle *tisci;
+	const struct ti_sci_rm_ringacc_ops *tisci_ring_ops;
+	u32 tisci_dev_id;
+};
+
+static long k3_ringacc_ring_get_fifo_pos(struct k3_ring *ring)
+{
+	return K3_RINGACC_FIFO_WINDOW_SIZE_BYTES -
+	       (4 << ring->elm_size);
+}
+
+static void *k3_ringacc_get_elm_addr(struct k3_ring *ring, u32 idx)
+{
+	return (ring->ring_mem_virt + idx * (4 << ring->elm_size));
+}
+
+static int k3_ringacc_ring_push_mem(struct k3_ring *ring, void *elem);
+static int k3_ringacc_ring_pop_mem(struct k3_ring *ring, void *elem);
+
+static struct k3_ring_ops k3_ring_mode_ring_ops = {
+		.push_tail = k3_ringacc_ring_push_mem,
+		.pop_head = k3_ringacc_ring_pop_mem,
+};
+
+static int k3_ringacc_ring_push_io(struct k3_ring *ring, void *elem);
+static int k3_ringacc_ring_pop_io(struct k3_ring *ring, void *elem);
+static int k3_ringacc_ring_push_head_io(struct k3_ring *ring, void *elem);
+static int k3_ringacc_ring_pop_tail_io(struct k3_ring *ring, void *elem);
+
+static struct k3_ring_ops k3_ring_mode_msg_ops = {
+		.push_tail = k3_ringacc_ring_push_io,
+		.push_head = k3_ringacc_ring_push_head_io,
+		.pop_tail = k3_ringacc_ring_pop_tail_io,
+		.pop_head = k3_ringacc_ring_pop_io,
+};
+
+static int k3_ringacc_ring_push_head_proxy(struct k3_ring *ring, void *elem);
+static int k3_ringacc_ring_push_tail_proxy(struct k3_ring *ring, void *elem);
+static int k3_ringacc_ring_pop_head_proxy(struct k3_ring *ring, void *elem);
+static int k3_ringacc_ring_pop_tail_proxy(struct k3_ring *ring, void *elem);
+
+static struct k3_ring_ops k3_ring_mode_proxy_ops = {
+		.push_tail = k3_ringacc_ring_push_tail_proxy,
+		.push_head = k3_ringacc_ring_push_head_proxy,
+		.pop_tail = k3_ringacc_ring_pop_tail_proxy,
+		.pop_head = k3_ringacc_ring_pop_head_proxy,
+};
+
+static void k3_ringacc_ring_dump(struct k3_ring *ring)
+{
+	struct device *dev = ring->parent->dev;
+
+	dev_dbg(dev, "dump ring: %d\n", ring->ring_id);
+	dev_dbg(dev, "dump mem virt %p, dma %pad\n", ring->ring_mem_virt,
+		&ring->ring_mem_dma);
+	dev_dbg(dev, "dump elmsize %d, size %d, mode %d, proxy_id %d\n",
+		ring->elm_size, ring->size, ring->mode, ring->proxy_id);
+
+	dev_dbg(dev, "dump ring_rt_regs: db%08x\n", readl(&ring->rt->db));
+	dev_dbg(dev, "dump occ%08x\n", readl(&ring->rt->occ));
+	dev_dbg(dev, "dump indx%08x\n", readl(&ring->rt->indx));
+	dev_dbg(dev, "dump hwocc%08x\n", readl(&ring->rt->hwocc));
+	dev_dbg(dev, "dump hwindx%08x\n", readl(&ring->rt->hwindx));
+
+	if (ring->ring_mem_virt)
+		print_hex_dump_debug("dump ring_mem_virt ", DUMP_PREFIX_NONE,
+				     16, 1, ring->ring_mem_virt, 16 * 8, false);
+}
+
+struct k3_ring *k3_ringacc_request_ring(struct k3_ringacc *ringacc,
+					int id, u32 flags)
+{
+	int proxy_id = K3_RINGACC_PROXY_NOT_USED;
+
+	mutex_lock(&ringacc->req_lock);
+
+	if (id == K3_RINGACC_RING_ID_ANY) {
+		/* Request for any general purpose ring */
+		struct ti_sci_resource_desc *gp_rings =
+						&ringacc->rm_gp_range->desc[0];
+		unsigned long size;
+
+		size = gp_rings->start + gp_rings->num;
+		id = find_next_zero_bit(ringacc->rings_inuse, size,
+					gp_rings->start);
+		if (id == size)
+			goto error;
+	} else if (id < 0) {
+		goto error;
+	}
+
+	if (test_bit(id, ringacc->rings_inuse) &&
+	    !(ringacc->rings[id].flags & K3_RING_FLAG_SHARED))
+		goto error;
+	else if (ringacc->rings[id].flags & K3_RING_FLAG_SHARED)
+		goto out;
+
+	if (flags & K3_RINGACC_RING_USE_PROXY) {
+		proxy_id = find_next_zero_bit(ringacc->proxy_inuse,
+					      ringacc->num_proxies, 0);
+		if (proxy_id == ringacc->num_proxies)
+			goto error;
+	}
+
+	if (proxy_id != K3_RINGACC_PROXY_NOT_USED) {
+		set_bit(proxy_id, ringacc->proxy_inuse);
+		ringacc->rings[id].proxy_id = proxy_id;
+		dev_dbg(ringacc->dev, "Giving ring#%d proxy#%d\n", id,
+			proxy_id);
+	} else {
+		dev_dbg(ringacc->dev, "Giving ring#%d\n", id);
+	}
+
+	set_bit(id, ringacc->rings_inuse);
+out:
+	ringacc->rings[id].use_count++;
+	mutex_unlock(&ringacc->req_lock);
+	return &ringacc->rings[id];
+
+error:
+	mutex_unlock(&ringacc->req_lock);
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_request_ring);
+
+static void k3_ringacc_ring_reset_sci(struct k3_ring *ring)
+{
+	struct k3_ringacc *ringacc = ring->parent;
+	int ret;
+
+	ret = ringacc->tisci_ring_ops->config(
+			ringacc->tisci,
+			TI_SCI_MSG_VALUE_RM_RING_COUNT_VALID,
+			ringacc->tisci_dev_id,
+			ring->ring_id,
+			0,
+			0,
+			ring->size,
+			0,
+			0,
+			0);
+	if (ret)
+		dev_err(ringacc->dev, "TISCI reset ring fail (%d) ring_idx %d\n",
+			ret, ring->ring_id);
+}
+
+void k3_ringacc_ring_reset(struct k3_ring *ring)
+{
+	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
+		return;
+
+	ring->occ = 0;
+	ring->free = 0;
+	ring->rindex = 0;
+	ring->windex = 0;
+
+	k3_ringacc_ring_reset_sci(ring);
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_reset);
+
+static void k3_ringacc_ring_reconfig_qmode_sci(struct k3_ring *ring,
+					       enum k3_ring_mode mode)
+{
+	struct k3_ringacc *ringacc = ring->parent;
+	int ret;
+
+	ret = ringacc->tisci_ring_ops->config(
+			ringacc->tisci,
+			TI_SCI_MSG_VALUE_RM_RING_MODE_VALID,
+			ringacc->tisci_dev_id,
+			ring->ring_id,
+			0,
+			0,
+			0,
+			mode,
+			0,
+			0);
+	if (ret)
+		dev_err(ringacc->dev, "TISCI reconf qmode fail (%d) ring_idx %d\n",
+			ret, ring->ring_id);
+}
+
+void k3_ringacc_ring_reset_dma(struct k3_ring *ring, u32 occ)
+{
+	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
+		return;
+
+	if (!ring->parent->dma_ring_reset_quirk)
+		goto reset;
+
+	if (!occ)
+		occ = readl(&ring->rt->occ);
+
+	if (occ) {
+		u32 db_ring_cnt, db_ring_cnt_cur;
+
+		dev_dbg(ring->parent->dev, "%s %u occ: %u\n", __func__,
+			ring->ring_id, occ);
+		/* TI-SCI ring reset */
+		k3_ringacc_ring_reset_sci(ring);
+
+		/*
+		 * Setup the ring in ring/doorbell mode (if not already in this
+		 * mode)
+		 */
+		if (ring->mode != K3_RINGACC_RING_MODE_RING)
+			k3_ringacc_ring_reconfig_qmode_sci(
+					ring, K3_RINGACC_RING_MODE_RING);
+		/*
+		 * Ring the doorbell 2**22 – ringOcc times.
+		 * This will wrap the internal UDMAP ring state occupancy
+		 * counter (which is 21-bits wide) to 0.
+		 */
+		db_ring_cnt = (1U << 22) - occ;
+
+		while (db_ring_cnt != 0) {
+			/*
+			 * Ring the doorbell with the maximum count each
+			 * iteration if possible to minimize the total
+			 * of writes
+			 */
+			if (db_ring_cnt > K3_RINGACC_MAX_DB_RING_CNT)
+				db_ring_cnt_cur = K3_RINGACC_MAX_DB_RING_CNT;
+			else
+				db_ring_cnt_cur = db_ring_cnt;
+
+			writel(db_ring_cnt_cur, &ring->rt->db);
+			db_ring_cnt -= db_ring_cnt_cur;
+		}
+
+		/* Restore the original ring mode (if not ring mode) */
+		if (ring->mode != K3_RINGACC_RING_MODE_RING)
+			k3_ringacc_ring_reconfig_qmode_sci(ring, ring->mode);
+	}
+
+reset:
+	/* Reset the ring */
+	k3_ringacc_ring_reset(ring);
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_reset_dma);
+
+static void k3_ringacc_ring_free_sci(struct k3_ring *ring)
+{
+	struct k3_ringacc *ringacc = ring->parent;
+	int ret;
+
+	ret = ringacc->tisci_ring_ops->config(
+			ringacc->tisci,
+			TI_SCI_MSG_VALUE_RM_ALL_NO_ORDER,
+			ringacc->tisci_dev_id,
+			ring->ring_id,
+			0,
+			0,
+			0,
+			0,
+			0,
+			0);
+	if (ret)
+		dev_err(ringacc->dev, "TISCI ring free fail (%d) ring_idx %d\n",
+			ret, ring->ring_id);
+}
+
+int k3_ringacc_ring_free(struct k3_ring *ring)
+{
+	struct k3_ringacc *ringacc;
+
+	if (!ring)
+		return -EINVAL;
+
+	ringacc = ring->parent;
+
+	dev_dbg(ring->parent->dev, "flags: 0x%08x\n", ring->flags);
+
+	if (!test_bit(ring->ring_id, ringacc->rings_inuse))
+		return -EINVAL;
+
+	mutex_lock(&ringacc->req_lock);
+
+	if (--ring->use_count)
+		goto out;
+
+	if (!(ring->flags & K3_RING_FLAG_BUSY))
+		goto no_init;
+
+	k3_ringacc_ring_free_sci(ring);
+
+	dma_free_coherent(ringacc->dev,
+			  ring->size * (4 << ring->elm_size),
+			  ring->ring_mem_virt, ring->ring_mem_dma);
+	ring->flags = 0;
+	ring->ops = NULL;
+	if (ring->proxy_id != K3_RINGACC_PROXY_NOT_USED) {
+		clear_bit(ring->proxy_id, ringacc->proxy_inuse);
+		ring->proxy = NULL;
+		ring->proxy_id = K3_RINGACC_PROXY_NOT_USED;
+	}
+
+no_init:
+	clear_bit(ring->ring_id, ringacc->rings_inuse);
+
+out:
+	mutex_unlock(&ringacc->req_lock);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_free);
+
+u32 k3_ringacc_get_ring_id(struct k3_ring *ring)
+{
+	if (!ring)
+		return -EINVAL;
+
+	return ring->ring_id;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_get_ring_id);
+
+u32 k3_ringacc_get_tisci_dev_id(struct k3_ring *ring)
+{
+	if (!ring)
+		return -EINVAL;
+
+	return ring->parent->tisci_dev_id;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_get_tisci_dev_id);
+
+int k3_ringacc_get_ring_irq_num(struct k3_ring *ring)
+{
+	int irq_num;
+
+	if (!ring)
+		return -EINVAL;
+
+	irq_num = ti_sci_inta_msi_get_virq(ring->parent->dev, ring->ring_id);
+	if (irq_num <= 0)
+		irq_num = -EINVAL;
+	return irq_num;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_get_ring_irq_num);
+
+static int k3_ringacc_ring_cfg_sci(struct k3_ring *ring)
+{
+	struct k3_ringacc *ringacc = ring->parent;
+	u32 ring_idx;
+	int ret;
+
+	if (!ringacc->tisci)
+		return -EINVAL;
+
+	ring_idx = ring->ring_id;
+	ret = ringacc->tisci_ring_ops->config(
+			ringacc->tisci,
+			TI_SCI_MSG_VALUE_RM_ALL_NO_ORDER,
+			ringacc->tisci_dev_id,
+			ring_idx,
+			lower_32_bits(ring->ring_mem_dma),
+			upper_32_bits(ring->ring_mem_dma),
+			ring->size,
+			ring->mode,
+			ring->elm_size,
+			0);
+	if (ret)
+		dev_err(ringacc->dev, "TISCI config ring fail (%d) ring_idx %d\n",
+			ret, ring_idx);
+
+	return ret;
+}
+
+int k3_ringacc_ring_cfg(struct k3_ring *ring, struct k3_ring_cfg *cfg)
+{
+	struct k3_ringacc *ringacc = ring->parent;
+	int ret = 0;
+
+	if (!ring || !cfg)
+		return -EINVAL;
+	if (cfg->elm_size > K3_RINGACC_RING_ELSIZE_256 ||
+	    cfg->mode >= K3_RINGACC_RING_MODE_INVALID ||
+	    cfg->size & ~K3_RINGACC_CFG_RING_SIZE_ELCNT_MASK ||
+	    !test_bit(ring->ring_id, ringacc->rings_inuse))
+		return -EINVAL;
+
+	if (cfg->mode == K3_RINGACC_RING_MODE_MESSAGE &&
+	    ring->proxy_id == K3_RINGACC_PROXY_NOT_USED &&
+	    cfg->elm_size > K3_RINGACC_RING_ELSIZE_8) {
+		dev_err(ringacc->dev,
+			"Message mode must use proxy for %u element size\n",
+			4 << ring->elm_size);
+		return -EINVAL;
+	}
+
+	/*
+	 * In case of shared ring only the first user (master user) can
+	 * configure the ring. The sequence should be by the client:
+	 * ring = k3_ringacc_request_ring(ringacc, ring_id, 0); # master user
+	 * k3_ringacc_ring_cfg(ring, cfg); # master configuration
+	 * k3_ringacc_request_ring(ringacc, ring_id, K3_RING_FLAG_SHARED);
+	 * k3_ringacc_request_ring(ringacc, ring_id, K3_RING_FLAG_SHARED);
+	 */
+	if (ring->use_count != 1)
+		return 0;
+
+	ring->size = cfg->size;
+	ring->elm_size = cfg->elm_size;
+	ring->mode = cfg->mode;
+	ring->occ = 0;
+	ring->free = 0;
+	ring->rindex = 0;
+	ring->windex = 0;
+
+	if (ring->proxy_id != K3_RINGACC_PROXY_NOT_USED)
+		ring->proxy = ringacc->proxy_target_base +
+			      ring->proxy_id * K3_RINGACC_PROXY_TARGET_STEP;
+
+	switch (ring->mode) {
+	case K3_RINGACC_RING_MODE_RING:
+		ring->ops = &k3_ring_mode_ring_ops;
+		break;
+	case K3_RINGACC_RING_MODE_MESSAGE:
+		if (ring->proxy)
+			ring->ops = &k3_ring_mode_proxy_ops;
+		else
+			ring->ops = &k3_ring_mode_msg_ops;
+		break;
+	default:
+		ring->ops = NULL;
+		ret = -EINVAL;
+		goto err_free_proxy;
+	};
+
+	ring->ring_mem_virt = dma_alloc_coherent(ringacc->dev,
+					ring->size * (4 << ring->elm_size),
+					&ring->ring_mem_dma, GFP_KERNEL);
+	if (!ring->ring_mem_virt) {
+		dev_err(ringacc->dev, "Failed to alloc ring mem\n");
+		ret = -ENOMEM;
+		goto err_free_ops;
+	}
+
+	ret = k3_ringacc_ring_cfg_sci(ring);
+
+	if (ret)
+		goto err_free_mem;
+
+	ring->flags |= K3_RING_FLAG_BUSY;
+	ring->flags |= (cfg->flags & K3_RINGACC_RING_SHARED) ?
+			K3_RING_FLAG_SHARED : 0;
+
+	k3_ringacc_ring_dump(ring);
+
+	return 0;
+
+err_free_mem:
+	dma_free_coherent(ringacc->dev,
+			  ring->size * (4 << ring->elm_size),
+			  ring->ring_mem_virt,
+			  ring->ring_mem_dma);
+err_free_ops:
+	ring->ops = NULL;
+err_free_proxy:
+	ring->proxy = NULL;
+	return ret;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_cfg);
+
+u32 k3_ringacc_ring_get_size(struct k3_ring *ring)
+{
+	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
+		return -EINVAL;
+
+	return ring->size;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_get_size);
+
+u32 k3_ringacc_ring_get_free(struct k3_ring *ring)
+{
+	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
+		return -EINVAL;
+
+	if (!ring->free)
+		ring->free = ring->size - readl(&ring->rt->occ);
+
+	return ring->free;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_get_free);
+
+u32 k3_ringacc_ring_get_occ(struct k3_ring *ring)
+{
+	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
+		return -EINVAL;
+
+	return readl(&ring->rt->occ);
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_get_occ);
+
+u32 k3_ringacc_ring_is_full(struct k3_ring *ring)
+{
+	return !k3_ringacc_ring_get_free(ring);
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_is_full);
+
+enum k3_ringacc_access_mode {
+	K3_RINGACC_ACCESS_MODE_PUSH_HEAD,
+	K3_RINGACC_ACCESS_MODE_POP_HEAD,
+	K3_RINGACC_ACCESS_MODE_PUSH_TAIL,
+	K3_RINGACC_ACCESS_MODE_POP_TAIL,
+	K3_RINGACC_ACCESS_MODE_PEEK_HEAD,
+	K3_RINGACC_ACCESS_MODE_PEEK_TAIL,
+};
+
+#define K3_RINGACC_PROXY_MODE(x)	(((x) & 0x3) << 16)
+#define K3_RINGACC_PROXY_ELSIZE(x)	(((x) & 0x7) << 24)
+static int k3_ringacc_ring_cfg_proxy(struct k3_ring *ring,
+				     enum k3_ringacc_proxy_access_mode mode)
+{
+	u32 val;
+
+	val = ring->ring_id;
+	val |= K3_RINGACC_PROXY_MODE(mode);
+	val |= K3_RINGACC_PROXY_ELSIZE(ring->elm_size);
+	writel(val, &ring->proxy->control);
+	return 0;
+}
+
+static int k3_ringacc_ring_access_proxy(struct k3_ring *ring, void *elem,
+					enum k3_ringacc_access_mode access_mode)
+{
+	void __iomem *ptr;
+
+	ptr = (void __iomem *)&ring->proxy->data;
+
+	switch (access_mode) {
+	case K3_RINGACC_ACCESS_MODE_PUSH_HEAD:
+	case K3_RINGACC_ACCESS_MODE_POP_HEAD:
+		k3_ringacc_ring_cfg_proxy(ring, PROXY_ACCESS_MODE_HEAD);
+		break;
+	case K3_RINGACC_ACCESS_MODE_PUSH_TAIL:
+	case K3_RINGACC_ACCESS_MODE_POP_TAIL:
+		k3_ringacc_ring_cfg_proxy(ring, PROXY_ACCESS_MODE_TAIL);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	ptr += k3_ringacc_ring_get_fifo_pos(ring);
+
+	switch (access_mode) {
+	case K3_RINGACC_ACCESS_MODE_POP_HEAD:
+	case K3_RINGACC_ACCESS_MODE_POP_TAIL:
+		dev_dbg(ring->parent->dev,
+			"proxy:memcpy_fromio(x): --> ptr(%p), mode:%d\n", ptr,
+			access_mode);
+		memcpy_fromio(elem, ptr, (4 << ring->elm_size));
+		ring->occ--;
+		break;
+	case K3_RINGACC_ACCESS_MODE_PUSH_TAIL:
+	case K3_RINGACC_ACCESS_MODE_PUSH_HEAD:
+		dev_dbg(ring->parent->dev,
+			"proxy:memcpy_toio(x): --> ptr(%p), mode:%d\n", ptr,
+			access_mode);
+		memcpy_toio(ptr, elem, (4 << ring->elm_size));
+		ring->free--;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	dev_dbg(ring->parent->dev, "proxy: free%d occ%d\n", ring->free,
+		ring->occ);
+	return 0;
+}
+
+static int k3_ringacc_ring_push_head_proxy(struct k3_ring *ring, void *elem)
+{
+	return k3_ringacc_ring_access_proxy(ring, elem,
+					    K3_RINGACC_ACCESS_MODE_PUSH_HEAD);
+}
+
+static int k3_ringacc_ring_push_tail_proxy(struct k3_ring *ring, void *elem)
+{
+	return k3_ringacc_ring_access_proxy(ring, elem,
+					    K3_RINGACC_ACCESS_MODE_PUSH_TAIL);
+}
+
+static int k3_ringacc_ring_pop_head_proxy(struct k3_ring *ring, void *elem)
+{
+	return k3_ringacc_ring_access_proxy(ring, elem,
+					    K3_RINGACC_ACCESS_MODE_POP_HEAD);
+}
+
+static int k3_ringacc_ring_pop_tail_proxy(struct k3_ring *ring, void *elem)
+{
+	return k3_ringacc_ring_access_proxy(ring, elem,
+					    K3_RINGACC_ACCESS_MODE_POP_HEAD);
+}
+
+static int k3_ringacc_ring_access_io(struct k3_ring *ring, void *elem,
+				     enum k3_ringacc_access_mode access_mode)
+{
+	void __iomem *ptr;
+
+	switch (access_mode) {
+	case K3_RINGACC_ACCESS_MODE_PUSH_HEAD:
+	case K3_RINGACC_ACCESS_MODE_POP_HEAD:
+		ptr = (void __iomem *)&ring->fifos->head_data;
+		break;
+	case K3_RINGACC_ACCESS_MODE_PUSH_TAIL:
+	case K3_RINGACC_ACCESS_MODE_POP_TAIL:
+		ptr = (void __iomem *)&ring->fifos->tail_data;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	ptr += k3_ringacc_ring_get_fifo_pos(ring);
+
+	switch (access_mode) {
+	case K3_RINGACC_ACCESS_MODE_POP_HEAD:
+	case K3_RINGACC_ACCESS_MODE_POP_TAIL:
+		dev_dbg(ring->parent->dev,
+			"memcpy_fromio(x): --> ptr(%p), mode:%d\n", ptr,
+			access_mode);
+		memcpy_fromio(elem, ptr, (4 << ring->elm_size));
+		ring->occ--;
+		break;
+	case K3_RINGACC_ACCESS_MODE_PUSH_TAIL:
+	case K3_RINGACC_ACCESS_MODE_PUSH_HEAD:
+		dev_dbg(ring->parent->dev,
+			"memcpy_toio(x): --> ptr(%p), mode:%d\n", ptr,
+			access_mode);
+		memcpy_toio(ptr, elem, (4 << ring->elm_size));
+		ring->free--;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	dev_dbg(ring->parent->dev, "free%d index%d occ%d index%d\n", ring->free,
+		ring->windex, ring->occ, ring->rindex);
+	return 0;
+}
+
+static int k3_ringacc_ring_push_head_io(struct k3_ring *ring, void *elem)
+{
+	return k3_ringacc_ring_access_io(ring, elem,
+					 K3_RINGACC_ACCESS_MODE_PUSH_HEAD);
+}
+
+static int k3_ringacc_ring_push_io(struct k3_ring *ring, void *elem)
+{
+	return k3_ringacc_ring_access_io(ring, elem,
+					 K3_RINGACC_ACCESS_MODE_PUSH_TAIL);
+}
+
+static int k3_ringacc_ring_pop_io(struct k3_ring *ring, void *elem)
+{
+	return k3_ringacc_ring_access_io(ring, elem,
+					 K3_RINGACC_ACCESS_MODE_POP_HEAD);
+}
+
+static int k3_ringacc_ring_pop_tail_io(struct k3_ring *ring, void *elem)
+{
+	return k3_ringacc_ring_access_io(ring, elem,
+					 K3_RINGACC_ACCESS_MODE_POP_HEAD);
+}
+
+static int k3_ringacc_ring_push_mem(struct k3_ring *ring, void *elem)
+{
+	void *elem_ptr;
+
+	elem_ptr = k3_ringacc_get_elm_addr(ring, ring->windex);
+
+	memcpy(elem_ptr, elem, (4 << ring->elm_size));
+
+	ring->windex = (ring->windex + 1) % ring->size;
+	ring->free--;
+	writel(1, &ring->rt->db);
+
+	dev_dbg(ring->parent->dev, "ring_push_mem: free%d index%d\n",
+		ring->free, ring->windex);
+
+	return 0;
+}
+
+static int k3_ringacc_ring_pop_mem(struct k3_ring *ring, void *elem)
+{
+	void *elem_ptr;
+
+	elem_ptr = k3_ringacc_get_elm_addr(ring, ring->rindex);
+
+	memcpy(elem, elem_ptr, (4 << ring->elm_size));
+
+	ring->rindex = (ring->rindex + 1) % ring->size;
+	ring->occ--;
+	writel(-1, &ring->rt->db);
+
+	dev_dbg(ring->parent->dev, "ring_pop_mem: occ%d index%d pos_ptr%p\n",
+		ring->occ, ring->rindex, elem_ptr);
+	return 0;
+}
+
+int k3_ringacc_ring_push(struct k3_ring *ring, void *elem)
+{
+	int ret = -EOPNOTSUPP;
+
+	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
+		return -EINVAL;
+
+	dev_dbg(ring->parent->dev, "ring_push: free%d index%d\n", ring->free,
+		ring->windex);
+
+	if (k3_ringacc_ring_is_full(ring))
+		return -ENOMEM;
+
+	if (ring->ops && ring->ops->push_tail)
+		ret = ring->ops->push_tail(ring, elem);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_push);
+
+int k3_ringacc_ring_push_head(struct k3_ring *ring, void *elem)
+{
+	int ret = -EOPNOTSUPP;
+
+	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
+		return -EINVAL;
+
+	dev_dbg(ring->parent->dev, "ring_push_head: free%d index%d\n",
+		ring->free, ring->windex);
+
+	if (k3_ringacc_ring_is_full(ring))
+		return -ENOMEM;
+
+	if (ring->ops && ring->ops->push_head)
+		ret = ring->ops->push_head(ring, elem);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_push_head);
+
+int k3_ringacc_ring_pop(struct k3_ring *ring, void *elem)
+{
+	int ret = -EOPNOTSUPP;
+
+	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
+		return -EINVAL;
+
+	if (!ring->occ)
+		ring->occ = k3_ringacc_ring_get_occ(ring);
+
+	dev_dbg(ring->parent->dev, "ring_pop: occ%d index%d\n", ring->occ,
+		ring->rindex);
+
+	if (!ring->occ)
+		return -ENODATA;
+
+	if (ring->ops && ring->ops->pop_head)
+		ret = ring->ops->pop_head(ring, elem);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_pop);
+
+int k3_ringacc_ring_pop_tail(struct k3_ring *ring, void *elem)
+{
+	int ret = -EOPNOTSUPP;
+
+	if (!ring || !(ring->flags & K3_RING_FLAG_BUSY))
+		return -EINVAL;
+
+	if (!ring->occ)
+		ring->occ = k3_ringacc_ring_get_occ(ring);
+
+	dev_dbg(ring->parent->dev, "ring_pop_tail: occ%d index%d\n", ring->occ,
+		ring->rindex);
+
+	if (!ring->occ)
+		return -ENODATA;
+
+	if (ring->ops && ring->ops->pop_tail)
+		ret = ring->ops->pop_tail(ring, elem);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(k3_ringacc_ring_pop_tail);
+
+struct k3_ringacc *of_k3_ringacc_get_by_phandle(struct device_node *np,
+						const char *property)
+{
+	struct device_node *ringacc_np;
+	struct k3_ringacc *ringacc = ERR_PTR(-EPROBE_DEFER);
+	struct k3_ringacc *entry;
+
+	ringacc_np = of_parse_phandle(np, property, 0);
+	if (!ringacc_np)
+		return ERR_PTR(-ENODEV);
+
+	mutex_lock(&k3_ringacc_list_lock);
+	list_for_each_entry(entry, &k3_ringacc_list, list)
+		if (entry->dev->of_node == ringacc_np) {
+			ringacc = entry;
+			break;
+		}
+	mutex_unlock(&k3_ringacc_list_lock);
+	of_node_put(ringacc_np);
+
+	return ringacc;
+}
+EXPORT_SYMBOL_GPL(of_k3_ringacc_get_by_phandle);
+
+static int k3_ringacc_probe_dt(struct k3_ringacc *ringacc)
+{
+	struct device_node *node = ringacc->dev->of_node;
+	struct device *dev = ringacc->dev;
+	struct platform_device *pdev = to_platform_device(dev);
+	int ret;
+
+	if (!node) {
+		dev_err(dev, "device tree info unavailable\n");
+		return -ENODEV;
+	}
+
+	ret = of_property_read_u32(node, "ti,num-rings", &ringacc->num_rings);
+	if (ret) {
+		dev_err(dev, "ti,num-rings read failure %d\n", ret);
+		return ret;
+	}
+
+	ringacc->dma_ring_reset_quirk =
+			of_property_read_bool(node, "ti,dma-ring-reset-quirk");
+
+	ringacc->tisci = ti_sci_get_by_phandle(node, "ti,sci");
+	if (IS_ERR(ringacc->tisci)) {
+		ret = PTR_ERR(ringacc->tisci);
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "ti,sci read fail %d\n", ret);
+		ringacc->tisci = NULL;
+		return ret;
+	}
+
+	ret = of_property_read_u32(node, "ti,sci-dev-id",
+				   &ringacc->tisci_dev_id);
+	if (ret) {
+		dev_err(dev, "ti,sci-dev-id read fail %d\n", ret);
+		return ret;
+	}
+
+	pdev->id = ringacc->tisci_dev_id;
+
+	ringacc->rm_gp_range = devm_ti_sci_get_of_resource(ringacc->tisci, dev,
+						ringacc->tisci_dev_id,
+						"ti,sci-rm-range-gp-rings");
+	if (IS_ERR(ringacc->rm_gp_range)) {
+		dev_err(dev, "Failed to allocate MSI interrupts\n");
+		return PTR_ERR(ringacc->rm_gp_range);
+	}
+
+	return ti_sci_inta_msi_domain_alloc_irqs(ringacc->dev,
+						 ringacc->rm_gp_range);
+}
+
+static int k3_ringacc_probe(struct platform_device *pdev)
+{
+	struct k3_ringacc *ringacc;
+	void __iomem *base_fifo, *base_rt;
+	struct device *dev = &pdev->dev;
+	struct resource *res;
+	int ret, i;
+
+	ringacc = devm_kzalloc(dev, sizeof(*ringacc), GFP_KERNEL);
+	if (!ringacc)
+		return -ENOMEM;
+
+	ringacc->dev = dev;
+	mutex_init(&ringacc->req_lock);
+
+	dev->msi_domain = of_msi_get_domain(dev, dev->of_node,
+					    DOMAIN_BUS_TI_SCI_INTA_MSI);
+	if (!dev->msi_domain) {
+		dev_err(dev, "Failed to get MSI domain\n");
+		return -EPROBE_DEFER;
+	}
+
+	ret = k3_ringacc_probe_dt(ringacc);
+	if (ret)
+		return ret;
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "rt");
+	base_rt = devm_ioremap_resource(dev, res);
+	if (IS_ERR(base_rt))
+		return PTR_ERR(base_rt);
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "fifos");
+	base_fifo = devm_ioremap_resource(dev, res);
+	if (IS_ERR(base_fifo))
+		return PTR_ERR(base_fifo);
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "proxy_gcfg");
+	ringacc->proxy_gcfg = devm_ioremap_resource(dev, res);
+	if (IS_ERR(ringacc->proxy_gcfg))
+		return PTR_ERR(ringacc->proxy_gcfg);
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
+					   "proxy_target");
+	ringacc->proxy_target_base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(ringacc->proxy_target_base))
+		return PTR_ERR(ringacc->proxy_target_base);
+
+	ringacc->num_proxies = readl(&ringacc->proxy_gcfg->config) &
+				     K3_RINGACC_PROXY_CFG_THREADS_MASK;
+
+	ringacc->rings = devm_kzalloc(dev,
+				      sizeof(*ringacc->rings) *
+				      ringacc->num_rings,
+				      GFP_KERNEL);
+	ringacc->rings_inuse = devm_kcalloc(dev,
+					    BITS_TO_LONGS(ringacc->num_rings),
+					    sizeof(unsigned long), GFP_KERNEL);
+	ringacc->proxy_inuse = devm_kcalloc(dev,
+					    BITS_TO_LONGS(ringacc->num_proxies),
+					    sizeof(unsigned long), GFP_KERNEL);
+
+	if (!ringacc->rings || !ringacc->rings_inuse || !ringacc->proxy_inuse)
+		return -ENOMEM;
+
+	for (i = 0; i < ringacc->num_rings; i++) {
+		ringacc->rings[i].rt = base_rt +
+				       K3_RINGACC_RT_REGS_STEP * i;
+		ringacc->rings[i].fifos = base_fifo +
+					  K3_RINGACC_FIFO_REGS_STEP * i;
+		ringacc->rings[i].parent = ringacc;
+		ringacc->rings[i].ring_id = i;
+		ringacc->rings[i].proxy_id = K3_RINGACC_PROXY_NOT_USED;
+	}
+	dev_set_drvdata(dev, ringacc);
+
+	ringacc->tisci_ring_ops = &ringacc->tisci->ops.rm_ring_ops;
+
+	mutex_lock(&k3_ringacc_list_lock);
+	list_add_tail(&ringacc->list, &k3_ringacc_list);
+	mutex_unlock(&k3_ringacc_list_lock);
+
+	dev_info(dev, "Ring Accelerator probed rings:%u, gp-rings[%u,%u] sci-dev-id:%u\n",
+		 ringacc->num_rings,
+		 ringacc->rm_gp_range->desc[0].start,
+		 ringacc->rm_gp_range->desc[0].num,
+		 ringacc->tisci_dev_id);
+	dev_info(dev, "dma-ring-reset-quirk: %s\n",
+		 ringacc->dma_ring_reset_quirk ? "enabled" : "disabled");
+	dev_info(dev, "RA Proxy rev. %08x, num_proxies:%u\n",
+		 readl(&ringacc->proxy_gcfg->revision), ringacc->num_proxies);
+	return 0;
+}
+
+/* Match table for of_platform binding */
+static const struct of_device_id k3_ringacc_of_match[] = {
+	{ .compatible = "ti,am654-navss-ringacc", },
+	{},
+};
+
+static struct platform_driver k3_ringacc_driver = {
+	.probe		= k3_ringacc_probe,
+	.driver		= {
+		.name	= "k3-ringacc",
+		.of_match_table = k3_ringacc_of_match,
+		.suppress_bind_attrs = true,
+	},
+};
+builtin_platform_driver(k3_ringacc_driver);

include/linux/soc/ti/k3-ringacc.h

···
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * K3 Ring Accelerator (RA) subsystem interface
+ *
+ * Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com
+ */
+
+#ifndef __SOC_TI_K3_RINGACC_API_H_
+#define __SOC_TI_K3_RINGACC_API_H_
+
+#include <linux/types.h>
+
+struct device_node;
+
+/**
+ * enum k3_ring_mode - &struct k3_ring_cfg mode
+ *
+ * RA ring operational modes
+ *
+ * @K3_RINGACC_RING_MODE_RING: Exposed Ring mode for SW direct access
+ * @K3_RINGACC_RING_MODE_MESSAGE: Messaging mode. Messaging mode requires
+ *	that all accesses to the queue must go through this IP so that all
+ *	accesses to the memory are controlled and ordered. This IP then
+ *	controls the entire state of the queue, and SW has no directly control,
+ *	such as through doorbells and cannot access the storage memory directly.
+ *	This is particularly useful when more than one SW or HW entity can be
+ *	the producer and/or consumer at the same time
+ * @K3_RINGACC_RING_MODE_CREDENTIALS: Credentials mode is message mode plus
+ *	stores credentials with each message, requiring the element size to be
+ *	doubled to fit the credentials. Any exposed memory should be protected
+ *	by a firewall from unwanted access
+ */
+enum k3_ring_mode {
+	K3_RINGACC_RING_MODE_RING = 0,
+	K3_RINGACC_RING_MODE_MESSAGE,
+	K3_RINGACC_RING_MODE_CREDENTIALS,
+	K3_RINGACC_RING_MODE_INVALID
+};
+
+/**
+ * enum k3_ring_size - &struct k3_ring_cfg elm_size
+ *
+ * RA ring element's sizes in bytes.
+ */
+enum k3_ring_size {
+	K3_RINGACC_RING_ELSIZE_4 = 0,
+	K3_RINGACC_RING_ELSIZE_8,
+	K3_RINGACC_RING_ELSIZE_16,
+	K3_RINGACC_RING_ELSIZE_32,
+	K3_RINGACC_RING_ELSIZE_64,
+	K3_RINGACC_RING_ELSIZE_128,
+	K3_RINGACC_RING_ELSIZE_256,
+	K3_RINGACC_RING_ELSIZE_INVALID
+};
+
+struct k3_ringacc;
+struct k3_ring;
+
+/**
+ * enum k3_ring_cfg - RA ring configuration structure
+ *
+ * @size: Ring size, number of elements
+ * @elm_size: Ring element size
+ * @mode: Ring operational mode
+ * @flags: Ring configuration flags. Possible values:
+ *	 @K3_RINGACC_RING_SHARED: when set allows to request the same ring
+ *	 few times. It's usable when the same ring is used as Free Host PD ring
+ *	 for different flows, for example.
+ *	 Note: Locking should be done by consumer if required
+ */
+struct k3_ring_cfg {
+	u32 size;
+	enum k3_ring_size elm_size;
+	enum k3_ring_mode mode;
+#define K3_RINGACC_RING_SHARED BIT(1)
+	u32 flags;
+};
+
+#define K3_RINGACC_RING_ID_ANY (-1)
+
+/**
+ * of_k3_ringacc_get_by_phandle - find a RA by phandle property
+ * @np: device node
+ * @propname: property name containing phandle on RA node
+ *
+ * Returns pointer on the RA - struct k3_ringacc
+ * or -ENODEV if not found,
+ * or -EPROBE_DEFER if not yet registered
+ */
+struct k3_ringacc *of_k3_ringacc_get_by_phandle(struct device_node *np,
+						const char *property);
+
+#define K3_RINGACC_RING_USE_PROXY BIT(1)
+
+/**
+ * k3_ringacc_request_ring - request ring from ringacc
+ * @ringacc: pointer on ringacc
+ * @id: ring id or K3_RINGACC_RING_ID_ANY for any general purpose ring
+ * @flags:
+ *	@K3_RINGACC_RING_USE_PROXY: if set - proxy will be allocated and
+ *		used to access ring memory. Sopported only for rings in
+ *		Message/Credentials/Queue mode.
+ *
+ * Returns pointer on the Ring - struct k3_ring
+ * or NULL in case of failure.
+ */
+struct k3_ring *k3_ringacc_request_ring(struct k3_ringacc *ringacc,
+					int id, u32 flags);
+
+/**
+ * k3_ringacc_ring_reset - ring reset
+ * @ring: pointer on Ring
+ *
+ * Resets ring internal state ((hw)occ, (hw)idx).
+ */
+void k3_ringacc_ring_reset(struct k3_ring *ring);
+/**
+ * k3_ringacc_ring_reset - ring reset for DMA rings
+ * @ring: pointer on Ring
+ *
+ * Resets ring internal state ((hw)occ, (hw)idx). Should be used for rings
+ * which are read by K3 UDMA, like TX or Free Host PD rings.
+ */
+void k3_ringacc_ring_reset_dma(struct k3_ring *ring, u32 occ);
+
+/**
+ * k3_ringacc_ring_free - ring free
+ * @ring: pointer on Ring
+ *
+ * Resets ring and free all alocated resources.
+ */
+int k3_ringacc_ring_free(struct k3_ring *ring);
+
+/**
+ * k3_ringacc_get_ring_id - Get the Ring ID
+ * @ring: pointer on ring
+ *
+ * Returns the Ring ID
+ */
+u32 k3_ringacc_get_ring_id(struct k3_ring *ring);
+
+/**
+ * k3_ringacc_get_ring_irq_num - Get the irq number for the ring
+ * @ring: pointer on ring
+ *
+ * Returns the interrupt number which can be used to request the interrupt
+ */
+int k3_ringacc_get_ring_irq_num(struct k3_ring *ring);
+
+/**
+ * k3_ringacc_ring_cfg - ring configure
+ * @ring: pointer on ring
+ * @cfg: Ring configuration parameters (see &struct k3_ring_cfg)
+ *
+ * Configures ring, including ring memory allocation.
+ * Returns 0 on success, errno otherwise.
+ */
+int k3_ringacc_ring_cfg(struct k3_ring *ring, struct k3_ring_cfg *cfg);
+
+/**
+ * k3_ringacc_ring_get_size - get ring size
+ * @ring: pointer on ring
+ *
+ * Returns ring size in number of elements.
+ */
+u32 k3_ringacc_ring_get_size(struct k3_ring *ring);
+
+/**
+ * k3_ringacc_ring_get_free - get free elements
+ * @ring: pointer on ring
+ *
+ * Returns number of free elements in the ring.
+ */
+u32 k3_ringacc_ring_get_free(struct k3_ring *ring);
+
+/**
+ * k3_ringacc_ring_get_occ - get ring occupancy
+ * @ring: pointer on ring
+ *
+ * Returns total number of valid entries on the ring
+ */
+u32 k3_ringacc_ring_get_occ(struct k3_ring *ring);
+
+/**
+ * k3_ringacc_ring_is_full - checks if ring is full
+ * @ring: pointer on ring
+ *
+ * Returns true if the ring is full
+ */
+u32 k3_ringacc_ring_is_full(struct k3_ring *ring);
+
+/**
+ * k3_ringacc_ring_push - push element to the ring tail
+ * @ring: pointer on ring
+ * @elem: pointer on ring element buffer
+ *
+ * Push one ring element to the ring tail. Size of the ring element is
+ * determined by ring configuration &struct k3_ring_cfg elm_size.
+ *
+ * Returns 0 on success, errno otherwise.
+ */
+int k3_ringacc_ring_push(struct k3_ring *ring, void *elem);
+
+/**
+ * k3_ringacc_ring_pop - pop element from the ring head
+ * @ring: pointer on ring
+ * @elem: pointer on ring element buffer
+ *
+ * Push one ring element from the ring head. Size of the ring element is
+ * determined by ring configuration &struct k3_ring_cfg elm_size..
+ *
+ * Returns 0 on success, errno otherwise.
+ */
+int k3_ringacc_ring_pop(struct k3_ring *ring, void *elem);
+
+/**
+ * k3_ringacc_ring_push_head - push element to the ring head
+ * @ring: pointer on ring
+ * @elem: pointer on ring element buffer
+ *
+ * Push one ring element to the ring head. Size of the ring element is
+ * determined by ring configuration &struct k3_ring_cfg elm_size.
+ *
+ * Returns 0 on success, errno otherwise.
+ * Not Supported by ring modes: K3_RINGACC_RING_MODE_RING
+ */
+int k3_ringacc_ring_push_head(struct k3_ring *ring, void *elem);
+
+/**
+ * k3_ringacc_ring_pop_tail - pop element from the ring tail
+ * @ring: pointer on ring
+ * @elem: pointer on ring element buffer
+ *
+ * Push one ring element from the ring tail. Size of the ring element is
+ * determined by ring configuration &struct k3_ring_cfg elm_size.
+ *
+ * Returns 0 on success, errno otherwise.
+ * Not Supported by ring modes: K3_RINGACC_RING_MODE_RING
+ */
+int k3_ringacc_ring_pop_tail(struct k3_ring *ring, void *elem);
+
+u32 k3_ringacc_get_tisci_dev_id(struct k3_ring *ring);
+
+#endif /* __SOC_TI_K3_RINGACC_API_H_ */