net: wwan: iosm: firmware flashing and coredump collection

This patch brings-in support for M.2 7560 Device firmware flashing &
coredump collection using devlink.
- Driver Registers with Devlink framework.
- Register devlink params callback for configuring device params
  required in flashing or coredump flow.
- Implements devlink ops flash_update callback that programs modem
  firmware.
- Creates region & snapshot required for device coredump log collection.

On early detection of device in boot rom stage. Driver registers with
Devlink framework and establish transport channel for PSI (Primary Signed
Image) injection. Once PSI is injected to device, the device execution
stage details are read to determine whether device is in flash or
exception mode. The collected information is reported to devlink user
space application & based on this informationi, application proceeds with
either modem firmware flashing or coredump collection.

Signed-off-by: M Chetan Kumar <m.chetan.kumar@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 317 insertions, 0 deletions

diff --git a/drivers/net/wwan/iosm/iosm_ipc_imem_ops.c b/drivers/net/wwan/iosm/iosm_ipc_imem_ops.c
index 0a472ce77370..b885a6570235 100644
--- a/drivers/net/wwan/iosm/iosm_ipc_imem_ops.c
+++ b/drivers/net/wwan/iosm/iosm_ipc_imem_ops.c
@@ -6,6 +6,7 @@
 #include <linux/delay.h>
 
 #include "iosm_ipc_chnl_cfg.h"
+#include "iosm_ipc_devlink.h"
 #include "iosm_ipc_imem.h"
 #include "iosm_ipc_imem_ops.h"
 #include "iosm_ipc_port.h"
@@ -331,3 +332,319 @@ int ipc_imem_sys_cdev_write(struct iosm_cdev *ipc_cdev, struct sk_buff *skb)
 out:
 	return ret;
 }
+
+/* Open a SIO link to CP and return the channel instance */
+struct ipc_mem_channel *ipc_imem_sys_devlink_open(struct iosm_imem *ipc_imem)
+{
+	struct ipc_mem_channel *channel;
+	enum ipc_phase phase;
+	int channel_id;
+
+	phase = ipc_imem_phase_update(ipc_imem);
+	switch (phase) {
+	case IPC_P_OFF:
+	case IPC_P_ROM:
+		/* Get a channel id as flash id and reserve it. */
+		channel_id = ipc_imem_channel_alloc(ipc_imem,
+						    IPC_MEM_CTRL_CHL_ID_7,
+						    IPC_CTYPE_CTRL);
+
+		if (channel_id < 0) {
+			dev_err(ipc_imem->dev,
+				"reservation of a flash channel id failed");
+			goto error;
+		}
+
+		ipc_imem->ipc_devlink->devlink_sio.channel_id = channel_id;
+		channel = &ipc_imem->channels[channel_id];
+
+		/* Enqueue chip info data to be read */
+		if (ipc_imem_devlink_trigger_chip_info(ipc_imem)) {
+			dev_err(ipc_imem->dev, "Enqueue of chip info failed");
+			channel->state = IMEM_CHANNEL_FREE;
+			goto error;
+		}
+
+		return channel;
+
+	case IPC_P_PSI:
+	case IPC_P_EBL:
+		ipc_imem->cp_version = ipc_mmio_get_cp_version(ipc_imem->mmio);
+		if (ipc_imem->cp_version == -1) {
+			dev_err(ipc_imem->dev, "invalid CP version");
+			goto error;
+		}
+
+		channel_id = ipc_imem->ipc_devlink->devlink_sio.channel_id;
+		return ipc_imem_channel_open(ipc_imem, channel_id,
+					     IPC_HP_CDEV_OPEN);
+
+	default:
+		/* CP is in the wrong state (e.g. CRASH or CD_READY) */
+		dev_err(ipc_imem->dev, "SIO open refused, phase %d", phase);
+	}
+error:
+	return NULL;
+}
+
+/* Release a SIO channel link to CP. */
+void ipc_imem_sys_devlink_close(struct iosm_devlink *ipc_devlink)
+{
+	struct iosm_imem *ipc_imem = ipc_devlink->pcie->imem;
+	int boot_check_timeout = BOOT_CHECK_DEFAULT_TIMEOUT;
+	enum ipc_mem_exec_stage exec_stage;
+	struct ipc_mem_channel *channel;
+	enum ipc_phase curr_phase;
+	int status = 0;
+	u32 tail = 0;
+
+	channel = ipc_imem->ipc_devlink->devlink_sio.channel;
+	curr_phase = ipc_imem->phase;
+	/* Increase the total wait time to boot_check_timeout */
+	do {
+		exec_stage = ipc_mmio_get_exec_stage(ipc_imem->mmio);
+		if (exec_stage == IPC_MEM_EXEC_STAGE_RUN ||
+		    exec_stage == IPC_MEM_EXEC_STAGE_PSI)
+			break;
+		msleep(20);
+		boot_check_timeout -= 20;
+	} while (boot_check_timeout > 0);
+
+	/* 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) {
+		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,
+				"Data Timeout on UL-Pipe:%d Head:%d Tail:%d",
+				channel->ul_pipe.pipe_nr,
+				channel->ul_pipe.old_head,
+				channel->ul_pipe.old_tail);
+		}
+	}
+
+	ipc_protocol_get_head_tail_index(ipc_imem->ipc_protocol,
+					 &channel->dl_pipe, NULL, &tail);
+
+	if (tail != channel->dl_pipe.old_tail) {
+		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,
+				"Data Timeout on DL-Pipe:%d Head:%d Tail:%d",
+				channel->dl_pipe.pipe_nr,
+				channel->dl_pipe.old_head,
+				channel->dl_pipe.old_tail);
+		}
+	}
+
+	/* 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;
+	/* Release the pipe resources */
+	ipc_imem_pipe_cleanup(ipc_imem, &channel->ul_pipe);
+	ipc_imem_pipe_cleanup(ipc_imem, &channel->dl_pipe);
+}
+
+void ipc_imem_sys_devlink_notify_rx(struct iosm_devlink *ipc_devlink,
+				    struct sk_buff *skb)
+{
+	skb_queue_tail(&ipc_devlink->devlink_sio.rx_list, skb);
+	complete(&ipc_devlink->devlink_sio.read_sem);
+}
+
+/* PSI transfer */
+static int ipc_imem_sys_psi_transfer(struct iosm_imem *ipc_imem,
+				     struct ipc_mem_channel *channel,
+				     unsigned char *buf, int count)
+{
+	int psi_start_timeout = PSI_START_DEFAULT_TIMEOUT;
+	enum ipc_mem_exec_stage exec_stage;
+
+	dma_addr_t mapping = 0;
+	int ret;
+
+	ret = ipc_pcie_addr_map(ipc_imem->pcie, buf, count, &mapping,
+				DMA_TO_DEVICE);
+	if (ret)
+		goto pcie_addr_map_fail;
+
+	/* Save the PSI information for the CP ROM driver on the doorbell
+	 * scratchpad.
+	 */
+	ipc_mmio_set_psi_addr_and_size(ipc_imem->mmio, mapping, count);
+	ipc_doorbell_fire(ipc_imem->pcie, 0, IPC_MEM_EXEC_STAGE_BOOT);
+
+	ret = wait_for_completion_interruptible_timeout
+		(&channel->ul_sem,
+		 msecs_to_jiffies(IPC_PSI_TRANSFER_TIMEOUT));
+
+	if (ret <= 0) {
+		dev_err(ipc_imem->dev, "Failed PSI transfer to CP, Error-%d",
+			ret);
+		goto psi_transfer_fail;
+	}
+	/* If the PSI download fails, return the CP boot ROM exit code */
+	if (ipc_imem->rom_exit_code != IMEM_ROM_EXIT_OPEN_EXT &&
+	    ipc_imem->rom_exit_code != IMEM_ROM_EXIT_CERT_EXT) {
+		ret = (-1) * ((int)ipc_imem->rom_exit_code);
+		goto psi_transfer_fail;
+	}
+
+	dev_dbg(ipc_imem->dev, "PSI image successfully downloaded");
+
+	/* Wait psi_start_timeout milliseconds until the CP PSI image is
+	 * running and updates the execution_stage field with
+	 * IPC_MEM_EXEC_STAGE_PSI. Verify the execution stage.
+	 */
+	do {
+		exec_stage = ipc_mmio_get_exec_stage(ipc_imem->mmio);
+
+		if (exec_stage == IPC_MEM_EXEC_STAGE_PSI)
+			break;
+
+		msleep(20);
+		psi_start_timeout -= 20;
+	} while (psi_start_timeout > 0);
+
+	if (exec_stage != IPC_MEM_EXEC_STAGE_PSI)
+		goto psi_transfer_fail; /* Unknown status of CP PSI process. */
+
+	ipc_imem->phase = IPC_P_PSI;
+
+	/* Enter the PSI phase. */
+	dev_dbg(ipc_imem->dev, "execution_stage[%X] eq. PSI", exec_stage);
+
+	/* Request the RUNNING state from CP and wait until it was reached
+	 * or timeout.
+	 */
+	ipc_imem_ipc_init_check(ipc_imem);
+
+	ret = wait_for_completion_interruptible_timeout
+		(&channel->ul_sem, msecs_to_jiffies(IPC_PSI_TRANSFER_TIMEOUT));
+	if (ret <= 0) {
+		dev_err(ipc_imem->dev,
+			"Failed PSI RUNNING state on CP, Error-%d", ret);
+		goto psi_transfer_fail;
+	}
+
+	if (ipc_mmio_get_ipc_state(ipc_imem->mmio) !=
+			IPC_MEM_DEVICE_IPC_RUNNING) {
+		dev_err(ipc_imem->dev,
+			"ch[%d] %s: unexpected CP IPC state %d, not RUNNING",
+			channel->channel_id,
+			ipc_imem_phase_get_string(ipc_imem->phase),
+			ipc_mmio_get_ipc_state(ipc_imem->mmio));
+
+		goto psi_transfer_fail;
+	}
+
+	/* Create the flash channel for the transfer of the images. */
+	if (!ipc_imem_sys_devlink_open(ipc_imem)) {
+		dev_err(ipc_imem->dev, "can't open flash_channel");
+		goto psi_transfer_fail;
+	}
+
+	ret = 0;
+psi_transfer_fail:
+	ipc_pcie_addr_unmap(ipc_imem->pcie, count, mapping, DMA_TO_DEVICE);
+pcie_addr_map_fail:
+	return ret;
+}
+
+int ipc_imem_sys_devlink_write(struct iosm_devlink *ipc_devlink,
+			       unsigned char *buf, int count)
+{
+	struct iosm_imem *ipc_imem = ipc_devlink->pcie->imem;
+	struct ipc_mem_channel *channel;
+	struct sk_buff *skb;
+	dma_addr_t mapping;
+	int ret;
+
+	channel = ipc_imem->ipc_devlink->devlink_sio.channel;
+
+	/* In the ROM phase the PSI image is passed to CP about a specific
+	 *  shared memory area and doorbell scratchpad directly.
+	 */
+	if (ipc_imem->phase == IPC_P_ROM) {
+		ret = ipc_imem_sys_psi_transfer(ipc_imem, channel, buf, count);
+		/* If the PSI transfer fails then send crash
+		 * Signature.
+		 */
+		if (ret > 0)
+			ipc_imem_msg_send_feature_set(ipc_imem,
+						      IPC_MEM_INBAND_CRASH_SIG,
+						      false);
+		goto out;
+	}
+
+	/* Allocate skb memory for the uplink buffer. */
+	skb = ipc_pcie_alloc_skb(ipc_devlink->pcie, count, GFP_KERNEL, &mapping,
+				 DMA_TO_DEVICE, 0);
+	if (!skb) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	memcpy(skb_put(skb, count), buf, count);
+
+	IPC_CB(skb)->op_type = UL_USR_OP_BLOCKED;
+
+	/* Add skb to the uplink skbuf accumulator. */
+	skb_queue_tail(&channel->ul_list, skb);
+
+	/* Inform the IPC tasklet to pass uplink IP packets to CP. */
+	if (!ipc_imem_call_cdev_write(ipc_imem)) {
+		ret = wait_for_completion_interruptible(&channel->ul_sem);
+
+		if (ret < 0) {
+			dev_err(ipc_imem->dev,
+				"ch[%d] no CP confirmation, status = %d",
+				channel->channel_id, ret);
+			ipc_pcie_kfree_skb(ipc_devlink->pcie, skb);
+			goto out;
+		}
+	}
+	ret = 0;
+out:
+	return ret;
+}
+
+int ipc_imem_sys_devlink_read(struct iosm_devlink *devlink, u8 *data,
+			      u32 bytes_to_read, u32 *bytes_read)
+{
+	struct sk_buff *skb = NULL;
+	int rc = 0;
+
+	/* check skb is available in rx_list or wait for skb */
+	devlink->devlink_sio.devlink_read_pend = 1;
+	while (!skb && !(skb = skb_dequeue(&devlink->devlink_sio.rx_list))) {
+		if (!wait_for_completion_interruptible_timeout
+				(&devlink->devlink_sio.read_sem,
+				 msecs_to_jiffies(IPC_READ_TIMEOUT))) {
+			dev_err(devlink->dev, "Read timedout");
+			rc =  -ETIMEDOUT;
+			goto devlink_read_fail;
+		}
+	}
+	devlink->devlink_sio.devlink_read_pend = 0;
+	if (bytes_to_read < skb->len) {
+		dev_err(devlink->dev, "Invalid size,expected len %d", skb->len);
+		rc = -EINVAL;
+		goto devlink_read_fail;
+	}
+	*bytes_read = skb->len;
+	memcpy(data, skb->data, skb->len);
+
+devlink_read_fail:
+	ipc_pcie_kfree_skb(devlink->pcie, skb);
+	return rc;
+}