2021-06-08 17:07:31

by M Chetan Kumar

[permalink] [raw]
Subject: [PATCH V4 05/16] net: iosm: shared memory I/O operations

1) Binds logical channel between host-device for communication.
2) Implements device specific(Char/Net) IO operations.

Signed-off-by: M Chetan Kumar <[email protected]>
---
v4: no change.
v3:
* WWAN port adaptation.
* Aligned ipc_ prefix for function name to be consistent across file.
v2:
* Change vlan_id to ip link if_id & document correction.
* Define new enums for IP & DSS session mapping.
* Return proper error code instead of returning -1.
* Clean-up vlan tag id & removed FW flashing logic.
drivers/net/wwan/iosm/iosm_ipc_imem_ops.c | 346 ++++++++++++++++++++++
drivers/net/wwan/iosm/iosm_ipc_imem_ops.h | 98 ++++++
2 files changed, 444 insertions(+)
create mode 100644 drivers/net/wwan/iosm/iosm_ipc_imem_ops.c
create mode 100644 drivers/net/wwan/iosm/iosm_ipc_imem_ops.h

diff --git a/drivers/net/wwan/iosm/iosm_ipc_imem_ops.c b/drivers/net/wwan/iosm/iosm_ipc_imem_ops.c
new file mode 100644
index 000000000000..46f76e8aae92
--- /dev/null
+++ b/drivers/net/wwan/iosm/iosm_ipc_imem_ops.c
@@ -0,0 +1,346 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020-21 Intel Corporation.
+ */
+
+#include <linux/delay.h>
+
+#include "iosm_ipc_chnl_cfg.h"
+#include "iosm_ipc_imem.h"
+#include "iosm_ipc_imem_ops.h"
+#include "iosm_ipc_port.h"
+#include "iosm_ipc_task_queue.h"
+
+/* Open a packet data online channel between the network layer and CP. */
+int ipc_imem_sys_wwan_open(struct iosm_imem *ipc_imem, int if_id)
+{
+ dev_dbg(ipc_imem->dev, "%s if id: %d",
+ ipc_imem_phase_get_string(ipc_imem->phase), if_id);
+
+ /* The network interface is only supported in the runtime phase. */
+ if (ipc_imem_phase_update(ipc_imem) != IPC_P_RUN) {
+ dev_err(ipc_imem->dev, "net:%d : refused phase %s", if_id,
+ ipc_imem_phase_get_string(ipc_imem->phase));
+ return -EIO;
+ }
+
+ /* check for the interafce id
+ * if if_id 1 to 8 then create IP MUX channel sessions.
+ * To start MUX session from 0 as network interface id would start
+ * from 1 so map it to if_id = if_id - 1
+ */
+ if (if_id >= IP_MUX_SESSION_START && if_id <= IP_MUX_SESSION_END)
+ return ipc_mux_open_session(ipc_imem->mux, if_id - 1);
+
+ return -EINVAL;
+}
+
+/* Release a net link to CP. */
+void ipc_imem_sys_wwan_close(struct iosm_imem *ipc_imem, int if_id,
+ int channel_id)
+{
+ if (ipc_imem->mux && if_id >= IP_MUX_SESSION_START &&
+ if_id <= IP_MUX_SESSION_END)
+ ipc_mux_close_session(ipc_imem->mux, if_id - 1);
+}
+
+/* Tasklet call to do uplink transfer. */
+static int ipc_imem_tq_cdev_write(struct iosm_imem *ipc_imem, int arg,
+ void *msg, size_t size)
+{
+ ipc_imem->ev_cdev_write_pending = false;
+ ipc_imem_ul_send(ipc_imem);
+
+ return 0;
+}
+
+/* Through tasklet to do sio write. */
+static int ipc_imem_call_cdev_write(struct iosm_imem *ipc_imem)
+{
+ if (ipc_imem->ev_cdev_write_pending)
+ return -1;
+
+ ipc_imem->ev_cdev_write_pending = true;
+
+ return ipc_task_queue_send_task(ipc_imem, ipc_imem_tq_cdev_write, 0,
+ NULL, 0, false);
+}
+
+/* Function for transfer UL data */
+int ipc_imem_sys_wwan_transmit(struct iosm_imem *ipc_imem,
+ int if_id, int channel_id, struct sk_buff *skb)
+{
+ int ret = -EINVAL;
+
+ if (!ipc_imem || channel_id < 0)
+ goto out;
+
+ /* Is CP Running? */
+ if (ipc_imem->phase != IPC_P_RUN) {
+ dev_dbg(ipc_imem->dev, "phase %s transmit",
+ ipc_imem_phase_get_string(ipc_imem->phase));
+ ret = -EIO;
+ goto out;
+ }
+
+ if (if_id >= IP_MUX_SESSION_START && if_id <= IP_MUX_SESSION_END)
+ /* Route the UL packet through IP MUX Layer */
+ ret = ipc_mux_ul_trigger_encode(ipc_imem->mux,
+ if_id - 1, skb);
+ else
+ dev_err(ipc_imem->dev,
+ "invalid if_id %d: ", if_id);
+out:
+ return ret;
+}
+
+/* Initialize wwan channel */
+void ipc_imem_wwan_channel_init(struct iosm_imem *ipc_imem,
+ enum ipc_mux_protocol mux_type)
+{
+ struct ipc_chnl_cfg chnl_cfg = { 0 };
+
+ ipc_imem->cp_version = ipc_mmio_get_cp_version(ipc_imem->mmio);
+
+ /* If modem version is invalid (0xffffffff), do not initialize WWAN. */
+ if (ipc_imem->cp_version == -1) {
+ dev_err(ipc_imem->dev, "invalid CP version");
+ return;
+ }
+
+ ipc_chnl_cfg_get(&chnl_cfg, ipc_imem->nr_of_channels);
+ ipc_imem_channel_init(ipc_imem, IPC_CTYPE_WWAN, chnl_cfg,
+ IRQ_MOD_OFF);
+
+ /* WWAN registration. */
+ ipc_imem->wwan = ipc_wwan_init(ipc_imem, ipc_imem->dev);
+ if (!ipc_imem->wwan)
+ dev_err(ipc_imem->dev,
+ "failed to register the ipc_wwan interfaces");
+}
+
+/* Map SKB to DMA for transfer */
+static int ipc_imem_map_skb_to_dma(struct iosm_imem *ipc_imem,
+ struct sk_buff *skb)
+{
+ struct iosm_pcie *ipc_pcie = ipc_imem->pcie;
+ char *buf = skb->data;
+ int len = skb->len;
+ dma_addr_t mapping;
+ int ret;
+
+ ret = ipc_pcie_addr_map(ipc_pcie, buf, len, &mapping, DMA_TO_DEVICE);
+
+ if (ret)
+ goto err;
+
+ BUILD_BUG_ON(sizeof(*IPC_CB(skb)) > sizeof(skb->cb));
+
+ IPC_CB(skb)->mapping = mapping;
+ IPC_CB(skb)->direction = DMA_TO_DEVICE;
+ IPC_CB(skb)->len = len;
+ IPC_CB(skb)->op_type = (u8)UL_DEFAULT;
+
+err:
+ return ret;
+}
+
+/* return true if channel is ready for use */
+static bool ipc_imem_is_channel_active(struct iosm_imem *ipc_imem,
+ struct ipc_mem_channel *channel)
+{
+ enum ipc_phase phase;
+
+ /* Update the current operation phase. */
+ phase = ipc_imem->phase;
+
+ /* Select the operation depending on the execution stage. */
+ switch (phase) {
+ case IPC_P_RUN:
+ case IPC_P_PSI:
+ case IPC_P_EBL:
+ break;
+
+ case IPC_P_ROM:
+ /* Prepare the PSI image for the CP ROM driver and
+ * suspend the flash app.
+ */
+ if (channel->state != IMEM_CHANNEL_RESERVED) {
+ dev_err(ipc_imem->dev,
+ "ch[%d]:invalid channel state %d,expected %d",
+ channel->channel_id, channel->state,
+ IMEM_CHANNEL_RESERVED);
+ goto channel_unavailable;
+ }
+ goto channel_available;
+
+ default:
+ /* Ignore uplink actions in all other phases. */
+ dev_err(ipc_imem->dev, "ch[%d]: confused phase %d",
+ channel->channel_id, phase);
+ goto channel_unavailable;
+ }
+ /* Check the full availability of the channel. */
+ if (channel->state != IMEM_CHANNEL_ACTIVE) {
+ dev_err(ipc_imem->dev, "ch[%d]: confused channel state %d",
+ channel->channel_id, channel->state);
+ goto channel_unavailable;
+ }
+
+channel_available:
+ return true;
+
+channel_unavailable:
+ return false;
+}
+
+/* Release a sio link to CP. */
+void ipc_imem_sys_cdev_close(struct iosm_cdev *ipc_cdev)
+{
+ struct iosm_imem *ipc_imem = ipc_cdev->ipc_imem;
+ struct ipc_mem_channel *channel = ipc_cdev->channel;
+ enum ipc_phase curr_phase;
+ int status = 0;
+ u32 tail = 0;
+
+ curr_phase = ipc_imem->phase;
+
+ /* If current phase is IPC_P_OFF or SIO ID is -ve then
+ * channel is already freed. Nothing to do.
+ */
+ if (curr_phase == IPC_P_OFF) {
+ dev_err(ipc_imem->dev,
+ "nothing to do. Current Phase: %s",
+ ipc_imem_phase_get_string(curr_phase));
+ return;
+ }
+
+ if (channel->state == IMEM_CHANNEL_FREE) {
+ dev_err(ipc_imem->dev, "ch[%d]: invalid channel state %d",
+ channel->channel_id, channel->state);
+ return;
+ }
+
+ /* If there are any pending TDs then wait for Timeout/Completion before
+ * closing pipe.
+ */
+ if (channel->ul_pipe.old_tail != channel->ul_pipe.old_head) {
+ ipc_imem->app_notify_ul_pend = 1;
+
+ /* Suspend the user app and wait a certain time for processing
+ * UL Data.
+ */
+ status = wait_for_completion_interruptible_timeout
+ (&ipc_imem->ul_pend_sem,
+ msecs_to_jiffies(IPC_PEND_DATA_TIMEOUT));
+ if (status == 0) {
+ dev_dbg(ipc_imem->dev,
+ "Pend data Timeout UL-Pipe:%d Head:%d Tail:%d",
+ channel->ul_pipe.pipe_nr,
+ channel->ul_pipe.old_head,
+ channel->ul_pipe.old_tail);
+ }
+
+ ipc_imem->app_notify_ul_pend = 0;
+ }
+
+ /* If there are any pending TDs then wait for Timeout/Completion before
+ * closing pipe.
+ */
+ ipc_protocol_get_head_tail_index(ipc_imem->ipc_protocol,
+ &channel->dl_pipe, NULL, &tail);
+
+ if (tail != channel->dl_pipe.old_tail) {
+ ipc_imem->app_notify_dl_pend = 1;
+
+ /* Suspend the user app and wait a certain time for processing
+ * DL Data.
+ */
+ status = wait_for_completion_interruptible_timeout
+ (&ipc_imem->dl_pend_sem,
+ msecs_to_jiffies(IPC_PEND_DATA_TIMEOUT));
+ if (status == 0) {
+ dev_dbg(ipc_imem->dev,
+ "Pend data Timeout DL-Pipe:%d Head:%d Tail:%d",
+ channel->dl_pipe.pipe_nr,
+ channel->dl_pipe.old_head,
+ channel->dl_pipe.old_tail);
+ }
+
+ ipc_imem->app_notify_dl_pend = 0;
+ }
+
+ /* Due to wait for completion in messages, there is a small window
+ * between closing the pipe and updating the channel is closed. In this
+ * small window there could be HP update from Host Driver. Hence update
+ * the channel state as CLOSING to aviod unnecessary interrupt
+ * towards CP.
+ */
+ channel->state = IMEM_CHANNEL_CLOSING;
+
+ ipc_imem_pipe_close(ipc_imem, &channel->ul_pipe);
+ ipc_imem_pipe_close(ipc_imem, &channel->dl_pipe);
+
+ ipc_imem_channel_free(channel);
+}
+
+/* Open a PORT link to CP and return the channel */
+struct ipc_mem_channel *ipc_imem_sys_port_open(struct iosm_imem *ipc_imem,
+ int chl_id, int hp_id)
+{
+ struct ipc_mem_channel *channel;
+ int ch_id;
+
+ /* The PORT interface is only supported in the runtime phase. */
+ if (ipc_imem_phase_update(ipc_imem) != IPC_P_RUN) {
+ dev_err(ipc_imem->dev, "PORT open refused, phase %s",
+ ipc_imem_phase_get_string(ipc_imem->phase));
+ return NULL;
+ }
+
+ ch_id = ipc_imem_channel_alloc(ipc_imem, chl_id, IPC_CTYPE_CTRL);
+
+ if (ch_id < 0) {
+ dev_err(ipc_imem->dev, "reservation of an PORT chnl id failed");
+ return NULL;
+ }
+
+ channel = ipc_imem_channel_open(ipc_imem, ch_id, hp_id);
+
+ if (!channel) {
+ dev_err(ipc_imem->dev, "PORT channel id open failed");
+ return NULL;
+ }
+
+ return channel;
+}
+
+/* transfer skb to modem */
+int ipc_imem_sys_cdev_write(struct iosm_cdev *ipc_cdev, struct sk_buff *skb)
+{
+ struct ipc_mem_channel *channel = ipc_cdev->channel;
+ struct iosm_imem *ipc_imem = ipc_cdev->ipc_imem;
+ int ret = -EIO;
+
+ if (!ipc_imem_is_channel_active(ipc_imem, channel) ||
+ ipc_imem->phase == IPC_P_OFF_REQ)
+ goto out;
+
+ ret = ipc_imem_map_skb_to_dma(ipc_imem, skb);
+
+ if (ret)
+ goto out;
+
+ /* Add skb to the uplink skbuf accumulator. */
+ skb_queue_tail(&channel->ul_list, skb);
+
+ ret = ipc_imem_call_cdev_write(ipc_imem);
+
+ if (ret) {
+ skb_dequeue_tail(&channel->ul_list);
+ dev_err(ipc_cdev->dev, "channel id[%d] write failed\n",
+ ipc_cdev->channel->channel_id);
+ }
+out:
+ return ret;
+}
diff --git a/drivers/net/wwan/iosm/iosm_ipc_imem_ops.h b/drivers/net/wwan/iosm/iosm_ipc_imem_ops.h
new file mode 100644
index 000000000000..84087cf33329
--- /dev/null
+++ b/drivers/net/wwan/iosm/iosm_ipc_imem_ops.h
@@ -0,0 +1,98 @@
+/* SPDX-License-Identifier: GPL-2.0-only
+ *
+ * Copyright (C) 2020-21 Intel Corporation.
+ */
+
+#ifndef IOSM_IPC_IMEM_OPS_H
+#define IOSM_IPC_IMEM_OPS_H
+
+#include "iosm_ipc_mux_codec.h"
+
+/* Maximum wait time for blocking read */
+#define IPC_READ_TIMEOUT 500
+
+/* The delay in ms for defering the unregister */
+#define SIO_UNREGISTER_DEFER_DELAY_MS 1
+
+/* Default delay till CP PSI image is running and modem updates the
+ * execution stage.
+ * unit : milliseconds
+ */
+#define PSI_START_DEFAULT_TIMEOUT 3000
+
+/* Default time out when closing SIO, till the modem is in
+ * running state.
+ * unit : milliseconds
+ */
+#define BOOT_CHECK_DEFAULT_TIMEOUT 400
+
+/* IP MUX channel range */
+#define IP_MUX_SESSION_START 1
+#define IP_MUX_SESSION_END 8
+
+/**
+ * ipc_imem_sys_port_open - Open a port link to CP.
+ * @ipc_imem: Imem instance.
+ * @chl_id: Channel Indentifier.
+ * @hp_id: HP Indentifier.
+ *
+ * Return: channel instance on success, NULL for failure
+ */
+struct ipc_mem_channel *ipc_imem_sys_port_open(struct iosm_imem *ipc_imem,
+ int chl_id, int hp_id);
+
+/**
+ * ipc_imem_sys_cdev_close - Release a sio link to CP.
+ * @ipc_cdev: iosm sio instance.
+ */
+void ipc_imem_sys_cdev_close(struct iosm_cdev *ipc_cdev);
+
+/**
+ * ipc_imem_sys_cdev_write - Route the uplink buffer to CP.
+ * @ipc_cdev: iosm_cdev instance.
+ * @skb: Pointer to skb.
+ *
+ * Return: 0 on success and failure value on error
+ */
+int ipc_imem_sys_cdev_write(struct iosm_cdev *ipc_cdev, struct sk_buff *skb);
+
+/**
+ * ipc_imem_sys_wwan_open - Open packet data online channel between network
+ * layer and CP.
+ * @ipc_imem: Imem instance.
+ * @if_id: ip link tag of the net device.
+ *
+ * Return: Channel ID on success and failure value on error
+ */
+int ipc_imem_sys_wwan_open(struct iosm_imem *ipc_imem, int if_id);
+
+/**
+ * ipc_imem_sys_wwan_close - Close packet data online channel between network
+ * layer and CP.
+ * @ipc_imem: Imem instance.
+ * @if_id: IP link id net device.
+ * @channel_id: Channel ID to be closed.
+ */
+void ipc_imem_sys_wwan_close(struct iosm_imem *ipc_imem, int if_id,
+ int channel_id);
+
+/**
+ * ipc_imem_sys_wwan_transmit - Function for transfer UL data
+ * @ipc_imem: Imem instance.
+ * @if_id: link ID of the device.
+ * @channel_id: Channel ID used
+ * @skb: Pointer to sk buffer
+ *
+ * Return: 0 on success and failure value on error
+ */
+int ipc_imem_sys_wwan_transmit(struct iosm_imem *ipc_imem, int if_id,
+ int channel_id, struct sk_buff *skb);
+/**
+ * ipc_imem_wwan_channel_init - Initializes WWAN channels and the channel for
+ * MUX.
+ * @ipc_imem: Pointer to iosm_imem struct.
+ * @mux_type: Type of mux protocol.
+ */
+void ipc_imem_wwan_channel_init(struct iosm_imem *ipc_imem,
+ enum ipc_mux_protocol mux_type);
+#endif
--
2.25.1