--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2020 Samsung Electronics Co., Ltd.
+ * Copyright 2020 Google LLC.
+ * Copyright 2024 Linaro Ltd.
+ */
+#include <linux/bitfield.h>
+#include <linux/firmware/samsung/exynos-acpm-protocol.h>
+#include <linux/ktime.h>
+#include <linux/types.h>
+
+#include "exynos-acpm.h"
+#include "exynos-acpm-pmic.h"
+
+#define ACPM_PMIC_CHANNEL GENMASK(15, 12)
+#define ACPM_PMIC_TYPE GENMASK(11, 8)
+#define ACPM_PMIC_REG GENMASK(7, 0)
+
+#define ACPM_PMIC_RETURN GENMASK(31, 24)
+#define ACPM_PMIC_MASK GENMASK(23, 16)
+#define ACPM_PMIC_VALUE GENMASK(15, 8)
+#define ACPM_PMIC_FUNC GENMASK(7, 0)
+
+#define ACPM_PMIC_BULK_SHIFT 8
+#define ACPM_PMIC_BULK_MASK GENMASK(7, 0)
+#define ACPM_PMIC_BULK_MAX_COUNT 8
+
+enum exynos_acpm_pmic_func {
+ ACPM_PMIC_READ,
+ ACPM_PMIC_WRITE,
+ ACPM_PMIC_UPDATE,
+ ACPM_PMIC_BULK_READ,
+ ACPM_PMIC_BULK_WRITE,
+};
+
+static inline u32 acpm_pmic_set_bulk(u32 data, unsigned int i)
+{
+ return (data & ACPM_PMIC_BULK_MASK) << (ACPM_PMIC_BULK_SHIFT * i);
+}
+
+static inline u32 acpm_pmic_get_bulk(u32 data, unsigned int i)
+{
+ return (data >> (ACPM_PMIC_BULK_SHIFT * i)) & ACPM_PMIC_BULK_MASK;
+}
+
+static void acpm_pmic_set_xfer(struct acpm_xfer *xfer, u32 *cmd,
+ unsigned int acpm_chan_id)
+{
+ xfer->txd = cmd;
+ xfer->rxd = cmd;
+ xfer->txlen = sizeof(cmd);
+ xfer->rxlen = sizeof(cmd);
+ xfer->acpm_chan_id = acpm_chan_id;
+}
+
+static void acpm_pmic_init_read_cmd(u32 cmd[4], u8 type, u8 reg, u8 chan)
+{
+ cmd[0] = FIELD_PREP(ACPM_PMIC_TYPE, type) |
+ FIELD_PREP(ACPM_PMIC_REG, reg) |
+ FIELD_PREP(ACPM_PMIC_CHANNEL, chan);
+ cmd[1] = FIELD_PREP(ACPM_PMIC_FUNC, ACPM_PMIC_READ);
+ cmd[3] = ktime_to_ms(ktime_get());
+}
+
+int acpm_pmic_read_reg(const struct acpm_handle *handle,
+ unsigned int acpm_chan_id, u8 type, u8 reg, u8 chan,
+ u8 *buf)
+{
+ struct acpm_xfer xfer;
+ u32 cmd[4] = {0};
+ int ret;
+
+ acpm_pmic_init_read_cmd(cmd, type, reg, chan);
+ acpm_pmic_set_xfer(&xfer, cmd, acpm_chan_id);
+
+ ret = acpm_do_xfer(handle, &xfer);
+ if (ret)
+ return ret;
+
+ *buf = FIELD_GET(ACPM_PMIC_VALUE, xfer.rxd[1]);
+
+ return FIELD_GET(ACPM_PMIC_RETURN, xfer.rxd[1]);
+}
+
+static void acpm_pmic_init_bulk_read_cmd(u32 cmd[4], u8 type, u8 reg, u8 chan,
+ u8 count)
+{
+ cmd[0] = FIELD_PREP(ACPM_PMIC_TYPE, type) |
+ FIELD_PREP(ACPM_PMIC_REG, reg) |
+ FIELD_PREP(ACPM_PMIC_CHANNEL, chan);
+ cmd[1] = FIELD_PREP(ACPM_PMIC_FUNC, ACPM_PMIC_BULK_READ) |
+ FIELD_PREP(ACPM_PMIC_VALUE, count);
+}
+
+int acpm_pmic_bulk_read(const struct acpm_handle *handle,
+ unsigned int acpm_chan_id, u8 type, u8 reg, u8 chan,
+ u8 count, u8 *buf)
+{
+ struct acpm_xfer xfer;
+ u32 cmd[4] = {0};
+ int i, ret;
+
+ if (count > ACPM_PMIC_BULK_MAX_COUNT)
+ return -EINVAL;
+
+ acpm_pmic_init_bulk_read_cmd(cmd, type, reg, chan, count);
+ acpm_pmic_set_xfer(&xfer, cmd, acpm_chan_id);
+
+ ret = acpm_do_xfer(handle, &xfer);
+ if (ret)
+ return ret;
+
+ ret = FIELD_GET(ACPM_PMIC_RETURN, xfer.rxd[1]);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < count; i++) {
+ if (i < 4)
+ buf[i] = acpm_pmic_get_bulk(xfer.rxd[2], i);
+ else
+ buf[i] = acpm_pmic_get_bulk(xfer.rxd[3], i - 4);
+ }
+
+ return 0;
+}
+
+static void acpm_pmic_init_write_cmd(u32 cmd[4], u8 type, u8 reg, u8 chan,
+ u8 value)
+{
+ cmd[0] = FIELD_PREP(ACPM_PMIC_TYPE, type) |
+ FIELD_PREP(ACPM_PMIC_REG, reg) |
+ FIELD_PREP(ACPM_PMIC_CHANNEL, chan);
+ cmd[1] = FIELD_PREP(ACPM_PMIC_FUNC, ACPM_PMIC_WRITE) |
+ FIELD_PREP(ACPM_PMIC_VALUE, value);
+ cmd[3] = ktime_to_ms(ktime_get());
+}
+
+int acpm_pmic_write_reg(const struct acpm_handle *handle,
+ unsigned int acpm_chan_id, u8 type, u8 reg, u8 chan,
+ u8 value)
+{
+ struct acpm_xfer xfer;
+ u32 cmd[4] = {0};
+ int ret;
+
+ acpm_pmic_init_write_cmd(cmd, type, reg, chan, value);
+ acpm_pmic_set_xfer(&xfer, cmd, acpm_chan_id);
+
+ ret = acpm_do_xfer(handle, &xfer);
+ if (ret)
+ return ret;
+
+ return FIELD_GET(ACPM_PMIC_RETURN, xfer.rxd[1]);
+}
+
+static void acpm_pmic_init_bulk_write_cmd(u32 cmd[4], u8 type, u8 reg, u8 chan,
+ u8 count, const u8 *buf)
+{
+ int i;
+
+ cmd[0] = FIELD_PREP(ACPM_PMIC_TYPE, type) |
+ FIELD_PREP(ACPM_PMIC_REG, reg) |
+ FIELD_PREP(ACPM_PMIC_CHANNEL, chan);
+ cmd[1] = FIELD_PREP(ACPM_PMIC_FUNC, ACPM_PMIC_BULK_WRITE) |
+ FIELD_PREP(ACPM_PMIC_VALUE, count);
+
+ for (i = 0; i < count; i++) {
+ if (i < 4)
+ cmd[2] |= acpm_pmic_set_bulk(buf[i], i);
+ else
+ cmd[3] |= acpm_pmic_set_bulk(buf[i], i - 4);
+ }
+}
+
+int acpm_pmic_bulk_write(const struct acpm_handle *handle,
+ unsigned int acpm_chan_id, u8 type, u8 reg, u8 chan,
+ u8 count, const u8 *buf)
+{
+ struct acpm_xfer xfer;
+ u32 cmd[4] = {0};
+ int ret;
+
+ if (count > ACPM_PMIC_BULK_MAX_COUNT)
+ return -EINVAL;
+
+ acpm_pmic_init_bulk_write_cmd(cmd, type, reg, chan, count, buf);
+ acpm_pmic_set_xfer(&xfer, cmd, acpm_chan_id);
+
+ ret = acpm_do_xfer(handle, &xfer);
+ if (ret)
+ return ret;
+
+ return FIELD_GET(ACPM_PMIC_RETURN, xfer.rxd[1]);
+}
+
+static void acpm_pmic_init_update_cmd(u32 cmd[4], u8 type, u8 reg, u8 chan,
+ u8 value, u8 mask)
+{
+ cmd[0] = FIELD_PREP(ACPM_PMIC_TYPE, type) |
+ FIELD_PREP(ACPM_PMIC_REG, reg) |
+ FIELD_PREP(ACPM_PMIC_CHANNEL, chan);
+ cmd[1] = FIELD_PREP(ACPM_PMIC_FUNC, ACPM_PMIC_UPDATE) |
+ FIELD_PREP(ACPM_PMIC_VALUE, value) |
+ FIELD_PREP(ACPM_PMIC_MASK, mask);
+ cmd[3] = ktime_to_ms(ktime_get());
+}
+
+int acpm_pmic_update_reg(const struct acpm_handle *handle,
+ unsigned int acpm_chan_id, u8 type, u8 reg, u8 chan,
+ u8 value, u8 mask)
+{
+ struct acpm_xfer xfer;
+ u32 cmd[4] = {0};
+ int ret;
+
+ acpm_pmic_init_update_cmd(cmd, type, reg, chan, value, mask);
+ acpm_pmic_set_xfer(&xfer, cmd, acpm_chan_id);
+
+ ret = acpm_do_xfer(handle, &xfer);
+ if (ret)
+ return ret;
+
+ return FIELD_GET(ACPM_PMIC_RETURN, xfer.rxd[1]);
+}
--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2020 Samsung Electronics Co., Ltd.
+ * Copyright 2020 Google LLC.
+ * Copyright 2024 Linaro Ltd.
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bitmap.h>
+#include <linux/bits.h>
+#include <linux/cleanup.h>
+#include <linux/container_of.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/firmware/samsung/exynos-acpm-protocol.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/mailbox/exynos-message.h>
+#include <linux/mailbox_client.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/math.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#include "exynos-acpm.h"
+#include "exynos-acpm-pmic.h"
+
+#define ACPM_PROTOCOL_SEQNUM GENMASK(21, 16)
+
+/* The unit of counter is 20 us. 5000 * 20 = 100 ms */
+#define ACPM_POLL_TIMEOUT 5000
+#define ACPM_TX_TIMEOUT_US 500000
+
+#define ACPM_GS101_INITDATA_BASE 0xa000
+
+/**
+ * struct acpm_shmem - shared memory configuration information.
+ * @reserved: unused fields.
+ * @chans: offset to array of struct acpm_chan_shmem.
+ * @reserved1: unused fields.
+ * @num_chans: number of channels.
+ */
+struct acpm_shmem {
+ u32 reserved[2];
+ u32 chans;
+ u32 reserved1[3];
+ u32 num_chans;
+};
+
+/**
+ * struct acpm_chan_shmem - descriptor of a shared memory channel.
+ *
+ * @id: channel ID.
+ * @reserved: unused fields.
+ * @rx_rear: rear pointer of APM RX queue (TX for AP).
+ * @rx_front: front pointer of APM RX queue (TX for AP).
+ * @rx_base: base address of APM RX queue (TX for AP).
+ * @reserved1: unused fields.
+ * @tx_rear: rear pointer of APM TX queue (RX for AP).
+ * @tx_front: front pointer of APM TX queue (RX for AP).
+ * @tx_base: base address of APM TX queue (RX for AP).
+ * @qlen: queue length. Applies to both TX/RX queues.
+ * @mlen: message length. Applies to both TX/RX queues.
+ * @reserved2: unused fields.
+ * @poll_completion: true when the channel works on polling.
+ */
+struct acpm_chan_shmem {
+ u32 id;
+ u32 reserved[3];
+ u32 rx_rear;
+ u32 rx_front;
+ u32 rx_base;
+ u32 reserved1[3];
+ u32 tx_rear;
+ u32 tx_front;
+ u32 tx_base;
+ u32 qlen;
+ u32 mlen;
+ u32 reserved2[2];
+ u32 poll_completion;
+};
+
+/**
+ * struct acpm_queue - exynos acpm queue.
+ *
+ * @rear: rear address of the queue.
+ * @front: front address of the queue.
+ * @base: base address of the queue.
+ */
+struct acpm_queue {
+ void __iomem *rear;
+ void __iomem *front;
+ void __iomem *base;
+};
+
+/**
+ * struct acpm_rx_data - RX queue data.
+ *
+ * @cmd: pointer to where the data shall be saved.
+ * @n_cmd: number of 32-bit commands.
+ * @response: true if the client expects the RX data.
+ */
+struct acpm_rx_data {
+ u32 *cmd;
+ size_t n_cmd;
+ bool response;
+};
+
+#define ACPM_SEQNUM_MAX 64
+
+/**
+ * struct acpm_chan - driver internal representation of a channel.
+ * @cl: mailbox client.
+ * @chan: mailbox channel.
+ * @acpm: pointer to driver private data.
+ * @tx: TX queue. The enqueue is done by the host.
+ * - front index is written by the host.
+ * - rear index is written by the firmware.
+ *
+ * @rx: RX queue. The enqueue is done by the firmware.
+ * - front index is written by the firmware.
+ * - rear index is written by the host.
+ * @tx_lock: protects TX queue.
+ * @rx_lock: protects RX queue.
+ * @qlen: queue length. Applies to both TX/RX queues.
+ * @mlen: message length. Applies to both TX/RX queues.
+ * @seqnum: sequence number of the last message enqueued on TX queue.
+ * @id: channel ID.
+ * @poll_completion: indicates if the transfer needs to be polled for
+ * completion or interrupt mode is used.
+ * @bitmap_seqnum: bitmap that tracks the messages on the TX/RX queues.
+ * @rx_data: internal buffer used to drain the RX queue.
+ */
+struct acpm_chan {
+ struct mbox_client cl;
+ struct mbox_chan *chan;
+ struct acpm_info *acpm;
+ struct acpm_queue tx;
+ struct acpm_queue rx;
+ struct mutex tx_lock;
+ struct mutex rx_lock;
+
+ unsigned int qlen;
+ unsigned int mlen;
+ u8 seqnum;
+ u8 id;
+ bool poll_completion;
+
+ DECLARE_BITMAP(bitmap_seqnum, ACPM_SEQNUM_MAX - 1);
+ struct acpm_rx_data rx_data[ACPM_SEQNUM_MAX];
+};
+
+/**
+ * struct acpm_info - driver's private data.
+ * @shmem: pointer to the SRAM configuration data.
+ * @sram_base: base address of SRAM.
+ * @chans: pointer to the ACPM channel parameters retrieved from SRAM.
+ * @dev: pointer to the exynos-acpm device.
+ * @handle: instance of acpm_handle to send to clients.
+ * @num_chans: number of channels available for this controller.
+ */
+struct acpm_info {
+ struct acpm_shmem __iomem *shmem;
+ void __iomem *sram_base;
+ struct acpm_chan *chans;
+ struct device *dev;
+ struct acpm_handle handle;
+ u32 num_chans;
+};
+
+/**
+ * struct acpm_match_data - of_device_id data.
+ * @initdata_base: offset in SRAM where the channels configuration resides.
+ */
+struct acpm_match_data {
+ loff_t initdata_base;
+};
+
+#define client_to_acpm_chan(c) container_of(c, struct acpm_chan, cl)
+#define handle_to_acpm_info(h) container_of(h, struct acpm_info, handle)
+
+/**
+ * acpm_get_rx() - get response from RX queue.
+ * @achan: ACPM channel info.
+ * @xfer: reference to the transfer to get response for.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int acpm_get_rx(struct acpm_chan *achan, const struct acpm_xfer *xfer)
+{
+ u32 rx_front, rx_seqnum, tx_seqnum, seqnum;
+ const void __iomem *base, *addr;
+ struct acpm_rx_data *rx_data;
+ u32 i, val, mlen;
+ bool rx_set = false;
+
+ guard(mutex)(&achan->rx_lock);
+
+ rx_front = readl(achan->rx.front);
+ i = readl(achan->rx.rear);
+
+ /* Bail out if RX is empty. */
+ if (i == rx_front)
+ return 0;
+
+ base = achan->rx.base;
+ mlen = achan->mlen;
+
+ tx_seqnum = FIELD_GET(ACPM_PROTOCOL_SEQNUM, xfer->txd[0]);
+
+ /* Drain RX queue. */
+ do {
+ /* Read RX seqnum. */
+ addr = base + mlen * i;
+ val = readl(addr);
+
+ rx_seqnum = FIELD_GET(ACPM_PROTOCOL_SEQNUM, val);
+ if (!rx_seqnum)
+ return -EIO;
+ /*
+ * mssg seqnum starts with value 1, whereas the driver considers
+ * the first mssg at index 0.
+ */
+ seqnum = rx_seqnum - 1;
+ rx_data = &achan->rx_data[seqnum];
+
+ if (rx_data->response) {
+ if (rx_seqnum == tx_seqnum) {
+ __ioread32_copy(xfer->rxd, addr,
+ xfer->rxlen / 4);
+ rx_set = true;
+ clear_bit(seqnum, achan->bitmap_seqnum);
+ } else {
+ /*
+ * The RX data corresponds to another request.
+ * Save the data to drain the queue, but don't
+ * clear yet the bitmap. It will be cleared
+ * after the response is copied to the request.
+ */
+ __ioread32_copy(rx_data->cmd, addr,
+ xfer->rxlen / 4);
+ }
+ } else {
+ clear_bit(seqnum, achan->bitmap_seqnum);
+ }
+
+ i = (i + 1) % achan->qlen;
+ } while (i != rx_front);
+
+ /* We saved all responses, mark RX empty. */
+ writel(rx_front, achan->rx.rear);
+
+ /*
+ * If the response was not in this iteration of the queue, check if the
+ * RX data was previously saved.
+ */
+ rx_data = &achan->rx_data[tx_seqnum - 1];
+ if (!rx_set && rx_data->response) {
+ rx_seqnum = FIELD_GET(ACPM_PROTOCOL_SEQNUM,
+ rx_data->cmd[0]);
+
+ if (rx_seqnum == tx_seqnum) {
+ memcpy(xfer->rxd, rx_data->cmd, xfer->rxlen);
+ clear_bit(rx_seqnum - 1, achan->bitmap_seqnum);
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * acpm_dequeue_by_polling() - RX dequeue by polling.
+ * @achan: ACPM channel info.
+ * @xfer: reference to the transfer being waited for.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int acpm_dequeue_by_polling(struct acpm_chan *achan,
+ const struct acpm_xfer *xfer)
+{
+ struct device *dev = achan->acpm->dev;
+ unsigned int cnt_20us = 0;
+ u32 seqnum;
+ int ret;
+
+ seqnum = FIELD_GET(ACPM_PROTOCOL_SEQNUM, xfer->txd[0]);
+
+ do {
+ ret = acpm_get_rx(achan, xfer);
+ if (ret)
+ return ret;
+
+ if (!test_bit(seqnum - 1, achan->bitmap_seqnum))
+ return 0;
+
+ /* Determined experimentally. */
+ usleep_range(20, 30);
+ cnt_20us++;
+ } while (cnt_20us < ACPM_POLL_TIMEOUT);
+
+ dev_err(dev, "Timeout! ch:%u s:%u bitmap:%lx, cnt_20us = %d.\n",
+ achan->id, seqnum, achan->bitmap_seqnum[0], cnt_20us);
+
+ return -ETIME;
+}
+
+/**
+ * acpm_wait_for_queue_slots() - wait for queue slots.
+ *
+ * @achan: ACPM channel info.
+ * @next_tx_front: next front index of the TX queue.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int acpm_wait_for_queue_slots(struct acpm_chan *achan, u32 next_tx_front)
+{
+ u32 val, ret;
+
+ /*
+ * Wait for RX front to keep up with TX front. Make sure there's at
+ * least one element between them.
+ */
+ ret = readl_poll_timeout(achan->rx.front, val, next_tx_front != val, 0,
+ ACPM_TX_TIMEOUT_US);
+ if (ret) {
+ dev_err(achan->acpm->dev, "RX front can not keep up with TX front.\n");
+ return ret;
+ }
+
+ ret = readl_poll_timeout(achan->tx.rear, val, next_tx_front != val, 0,
+ ACPM_TX_TIMEOUT_US);
+ if (ret)
+ dev_err(achan->acpm->dev, "TX queue is full.\n");
+
+ return ret;
+}
+
+/**
+ * acpm_prepare_xfer() - prepare a transfer before writing the message to the
+ * TX queue.
+ * @achan: ACPM channel info.
+ * @xfer: reference to the transfer being prepared.
+ */
+static void acpm_prepare_xfer(struct acpm_chan *achan,
+ const struct acpm_xfer *xfer)
+{
+ struct acpm_rx_data *rx_data;
+ u32 *txd = (u32 *)xfer->txd;
+
+ /* Prevent chan->seqnum from being re-used */
+ do {
+ if (++achan->seqnum == ACPM_SEQNUM_MAX)
+ achan->seqnum = 1;
+ } while (test_bit(achan->seqnum - 1, achan->bitmap_seqnum));
+
+ txd[0] |= FIELD_PREP(ACPM_PROTOCOL_SEQNUM, achan->seqnum);
+
+ /* Clear data for upcoming responses */
+ rx_data = &achan->rx_data[achan->seqnum - 1];
+ memset(rx_data->cmd, 0, sizeof(*rx_data->cmd) * rx_data->n_cmd);
+ if (xfer->rxd)
+ rx_data->response = true;
+
+ /* Flag the index based on seqnum. (seqnum: 1~63, bitmap: 0~62) */
+ set_bit(achan->seqnum - 1, achan->bitmap_seqnum);
+}
+
+/**
+ * acpm_wait_for_message_response - an helper to group all possible ways of
+ * waiting for a synchronous message response.
+ *
+ * @achan: ACPM channel info.
+ * @xfer: reference to the transfer being waited for.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int acpm_wait_for_message_response(struct acpm_chan *achan,
+ const struct acpm_xfer *xfer)
+{
+ /* Just polling mode supported for now. */
+ return acpm_dequeue_by_polling(achan, xfer);
+}
+
+/**
+ * acpm_do_xfer() - do one transfer.
+ * @handle: pointer to the acpm handle.
+ * @xfer: transfer to initiate and wait for response.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+int acpm_do_xfer(const struct acpm_handle *handle, const struct acpm_xfer *xfer)
+{
+ struct acpm_info *acpm = handle_to_acpm_info(handle);
+ struct exynos_mbox_msg msg;
+ struct acpm_chan *achan;
+ u32 idx, tx_front;
+ int ret;
+
+ if (xfer->acpm_chan_id >= acpm->num_chans)
+ return -EINVAL;
+
+ achan = &acpm->chans[xfer->acpm_chan_id];
+
+ if (!xfer->txd || xfer->txlen > achan->mlen || xfer->rxlen > achan->mlen)
+ return -EINVAL;
+
+ if (!achan->poll_completion) {
+ dev_err(achan->acpm->dev, "Interrupt mode not supported\n");
+ return -EOPNOTSUPP;
+ }
+
+ scoped_guard(mutex, &achan->tx_lock) {
+ tx_front = readl(achan->tx.front);
+ idx = (tx_front + 1) % achan->qlen;
+
+ ret = acpm_wait_for_queue_slots(achan, idx);
+ if (ret)
+ return ret;
+
+ acpm_prepare_xfer(achan, xfer);
+
+ /* Write TX command. */
+ __iowrite32_copy(achan->tx.base + achan->mlen * tx_front,
+ xfer->txd, xfer->txlen / 4);
+
+ /* Advance TX front. */
+ writel(idx, achan->tx.front);
+ }
+
+ msg.chan_id = xfer->acpm_chan_id;
+ msg.chan_type = EXYNOS_MBOX_CHAN_TYPE_DOORBELL;
+ ret = mbox_send_message(achan->chan, (void *)&msg);
+ if (ret < 0)
+ return ret;
+
+ ret = acpm_wait_for_message_response(achan, xfer);
+
+ /*
+ * NOTE: we might prefer not to need the mailbox ticker to manage the
+ * transfer queueing since the protocol layer queues things by itself.
+ * Unfortunately, we have to kick the mailbox framework after we have
+ * received our message.
+ */
+ mbox_client_txdone(achan->chan, ret);
+
+ return ret;
+}
+
+/**
+ * acpm_chan_shmem_get_params() - get channel parameters and addresses of the
+ * TX/RX queues.
+ * @achan: ACPM channel info.
+ * @chan_shmem: __iomem pointer to a channel described in shared memory.
+ */
+static void acpm_chan_shmem_get_params(struct acpm_chan *achan,
+ struct acpm_chan_shmem __iomem *chan_shmem)
+{
+ void __iomem *base = achan->acpm->sram_base;
+ struct acpm_queue *rx = &achan->rx;
+ struct acpm_queue *tx = &achan->tx;
+
+ achan->mlen = readl(&chan_shmem->mlen);
+ achan->poll_completion = readl(&chan_shmem->poll_completion);
+ achan->id = readl(&chan_shmem->id);
+ achan->qlen = readl(&chan_shmem->qlen);
+
+ tx->base = base + readl(&chan_shmem->rx_base);
+ tx->rear = base + readl(&chan_shmem->rx_rear);
+ tx->front = base + readl(&chan_shmem->rx_front);
+
+ rx->base = base + readl(&chan_shmem->tx_base);
+ rx->rear = base + readl(&chan_shmem->tx_rear);
+ rx->front = base + readl(&chan_shmem->tx_front);
+
+ dev_vdbg(achan->acpm->dev, "ID = %d poll = %d, mlen = %d, qlen = %d\n",
+ achan->id, achan->poll_completion, achan->mlen, achan->qlen);
+}
+
+/**
+ * acpm_achan_alloc_cmds() - allocate buffers for retrieving data from the ACPM
+ * firmware.
+ * @achan: ACPM channel info.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int acpm_achan_alloc_cmds(struct acpm_chan *achan)
+{
+ struct device *dev = achan->acpm->dev;
+ struct acpm_rx_data *rx_data;
+ size_t cmd_size, n_cmd;
+ int i;
+
+ if (achan->mlen == 0)
+ return 0;
+
+ cmd_size = sizeof(*(achan->rx_data[0].cmd));
+ n_cmd = DIV_ROUND_UP_ULL(achan->mlen, cmd_size);
+
+ for (i = 0; i < ACPM_SEQNUM_MAX; i++) {
+ rx_data = &achan->rx_data[i];
+ rx_data->n_cmd = n_cmd;
+ rx_data->cmd = devm_kcalloc(dev, n_cmd, cmd_size, GFP_KERNEL);
+ if (!rx_data->cmd)
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+/**
+ * acpm_free_mbox_chans() - free mailbox channels.
+ * @acpm: pointer to driver data.
+ */
+static void acpm_free_mbox_chans(struct acpm_info *acpm)
+{
+ int i;
+
+ for (i = 0; i < acpm->num_chans; i++)
+ if (!IS_ERR_OR_NULL(acpm->chans[i].chan))
+ mbox_free_channel(acpm->chans[i].chan);
+}
+
+/**
+ * acpm_channels_init() - initialize channels based on the configuration data in
+ * the shared memory.
+ * @acpm: pointer to driver data.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int acpm_channels_init(struct acpm_info *acpm)
+{
+ struct acpm_shmem __iomem *shmem = acpm->shmem;
+ struct acpm_chan_shmem __iomem *chans_shmem;
+ struct device *dev = acpm->dev;
+ int i, ret;
+
+ acpm->num_chans = readl(&shmem->num_chans);
+ acpm->chans = devm_kcalloc(dev, acpm->num_chans, sizeof(*acpm->chans),
+ GFP_KERNEL);
+ if (!acpm->chans)
+ return -ENOMEM;
+
+ chans_shmem = acpm->sram_base + readl(&shmem->chans);
+
+ for (i = 0; i < acpm->num_chans; i++) {
+ struct acpm_chan_shmem __iomem *chan_shmem = &chans_shmem[i];
+ struct acpm_chan *achan = &acpm->chans[i];
+ struct mbox_client *cl = &achan->cl;
+
+ achan->acpm = acpm;
+
+ acpm_chan_shmem_get_params(achan, chan_shmem);
+
+ ret = acpm_achan_alloc_cmds(achan);
+ if (ret)
+ return ret;
+
+ mutex_init(&achan->rx_lock);
+ mutex_init(&achan->tx_lock);
+
+ cl->dev = dev;
+
+ achan->chan = mbox_request_channel(cl, 0);
+ if (IS_ERR(achan->chan)) {
+ acpm_free_mbox_chans(acpm);
+ return PTR_ERR(achan->chan);
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * acpm_setup_ops() - setup the operations structures.
+ * @acpm: pointer to the driver data.
+ */
+static void acpm_setup_ops(struct acpm_info *acpm)
+{
+ struct acpm_pmic_ops *pmic_ops = &acpm->handle.ops.pmic_ops;
+
+ pmic_ops->read_reg = acpm_pmic_read_reg;
+ pmic_ops->bulk_read = acpm_pmic_bulk_read;
+ pmic_ops->write_reg = acpm_pmic_write_reg;
+ pmic_ops->bulk_write = acpm_pmic_bulk_write;
+ pmic_ops->update_reg = acpm_pmic_update_reg;
+}
+
+static int acpm_probe(struct platform_device *pdev)
+{
+ const struct acpm_match_data *match_data;
+ struct device *dev = &pdev->dev;
+ struct device_node *shmem;
+ struct acpm_info *acpm;
+ resource_size_t size;
+ struct resource res;
+ int ret;
+
+ acpm = devm_kzalloc(dev, sizeof(*acpm), GFP_KERNEL);
+ if (!acpm)
+ return -ENOMEM;
+
+ shmem = of_parse_phandle(dev->of_node, "shmem", 0);
+ ret = of_address_to_resource(shmem, 0, &res);
+ of_node_put(shmem);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Failed to get shared memory.\n");
+
+ size = resource_size(&res);
+ acpm->sram_base = devm_ioremap(dev, res.start, size);
+ if (!acpm->sram_base)
+ return dev_err_probe(dev, -ENOMEM,
+ "Failed to ioremap shared memory.\n");
+
+ match_data = of_device_get_match_data(dev);
+ if (!match_data)
+ return dev_err_probe(dev, -EINVAL,
+ "Faile to get match data.\n");
+
+ acpm->shmem = acpm->sram_base + match_data->initdata_base;
+ acpm->dev = dev;
+
+ ret = acpm_channels_init(acpm);
+ if (ret)
+ return ret;
+
+ acpm_setup_ops(acpm);
+
+ platform_set_drvdata(pdev, acpm);
+
+ return 0;
+}
+
+/**
+ * acpm_handle_put() - release the handle acquired by acpm_get_by_phandle.
+ * @handle: Handle acquired by acpm_get_by_phandle.
+ */
+static void acpm_handle_put(const struct acpm_handle *handle)
+{
+ struct acpm_info *acpm = handle_to_acpm_info(handle);
+ struct device *dev = acpm->dev;
+
+ module_put(dev->driver->owner);
+ /* Drop reference taken with of_find_device_by_node(). */
+ put_device(dev);
+}
+
+/**
+ * devm_acpm_release() - devres release method.
+ * @dev: pointer to device.
+ * @res: pointer to resource.
+ */
+static void devm_acpm_release(struct device *dev, void *res)
+{
+ acpm_handle_put(*(struct acpm_handle **)res);
+}
+
+/**
+ * acpm_get_by_phandle() - get the ACPM handle using DT phandle.
+ * @dev: device pointer requesting ACPM handle.
+ * @property: property name containing phandle on ACPM node.
+ *
+ * Return: pointer to handle on success, ERR_PTR(-errno) otherwise.
+ */
+static const struct acpm_handle *acpm_get_by_phandle(struct device *dev,
+ const char *property)
+{
+ struct platform_device *pdev;
+ struct device_node *acpm_np;
+ struct device_link *link;
+ struct acpm_info *acpm;
+
+ acpm_np = of_parse_phandle(dev->of_node, property, 0);
+ if (!acpm_np)
+ return ERR_PTR(-ENODEV);
+
+ pdev = of_find_device_by_node(acpm_np);
+ if (!pdev) {
+ dev_err(dev, "Cannot find device node %s\n", acpm_np->name);
+ of_node_put(acpm_np);
+ return ERR_PTR(-EPROBE_DEFER);
+ }
+
+ of_node_put(acpm_np);
+
+ acpm = platform_get_drvdata(pdev);
+ if (!acpm) {
+ dev_err(dev, "Cannot get drvdata from %s\n",
+ dev_name(&pdev->dev));
+ platform_device_put(pdev);
+ return ERR_PTR(-EPROBE_DEFER);
+ }
+
+ if (!try_module_get(pdev->dev.driver->owner)) {
+ dev_err(dev, "Cannot get module reference.\n");
+ platform_device_put(pdev);
+ return ERR_PTR(-EPROBE_DEFER);
+ }
+
+ link = device_link_add(dev, &pdev->dev, DL_FLAG_AUTOREMOVE_SUPPLIER);
+ if (!link) {
+ dev_err(&pdev->dev,
+ "Failed to create device link to consumer %s.\n",
+ dev_name(dev));
+ platform_device_put(pdev);
+ module_put(pdev->dev.driver->owner);
+ return ERR_PTR(-EINVAL);
+ }
+
+ return &acpm->handle;
+}
+
+/**
+ * devm_acpm_get_by_phandle() - managed get handle using phandle.
+ * @dev: device pointer requesting ACPM handle.
+ * @property: property name containing phandle on ACPM node.
+ *
+ * Return: pointer to handle on success, ERR_PTR(-errno) otherwise.
+ */
+const struct acpm_handle *devm_acpm_get_by_phandle(struct device *dev,
+ const char *property)
+{
+ const struct acpm_handle **ptr, *handle;
+
+ ptr = devres_alloc(devm_acpm_release, sizeof(*ptr), GFP_KERNEL);
+ if (!ptr)
+ return ERR_PTR(-ENOMEM);
+
+ handle = acpm_get_by_phandle(dev, property);
+ if (!IS_ERR(handle)) {
+ *ptr = handle;
+ devres_add(dev, ptr);
+ } else {
+ devres_free(ptr);
+ }
+
+ return handle;
+}
+
+static const struct acpm_match_data acpm_gs101 = {
+ .initdata_base = ACPM_GS101_INITDATA_BASE,
+};
+
+static const struct of_device_id acpm_match[] = {
+ {
+ .compatible = "google,gs101-acpm-ipc",
+ .data = &acpm_gs101,
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, acpm_match);
+
+static struct platform_driver acpm_driver = {
+ .probe = acpm_probe,
+ .driver = {
+ .name = "exynos-acpm-protocol",
+ .of_match_table = acpm_match,
+ },
+};
+module_platform_driver(acpm_driver);
+
+MODULE_AUTHOR("Tudor Ambarus <tudor.ambarus@linaro.org>");
+MODULE_DESCRIPTION("Samsung Exynos ACPM mailbox protocol driver");
+MODULE_LICENSE("GPL");
projects / linux-block.git / commitdiff