Re: [PATCH v3] HID: intel-ish-hid: ISH firmware loader client driver

From: Nick Crews
Date: Fri Mar 29 2019 - 19:30:36 EST


On Fri, Mar 29, 2019 at 1:03 PM Rushikesh S Kadam
<rushikesh.s.kadam@xxxxxxxxx> wrote:
>
> This driver adds support for loading Intel Integrated
> Sensor Hub (ISH) firmware from host file system to ISH
> SRAM and start execution.
>
> At power-on, the ISH subsystem shall boot to an interim
> Shim loader-firmware, which shall expose an ISHTP loader
> device.
>
> The driver implements an ISHTP client that communicates
> with the Shim ISHTP loader device over the intel-ish-hid
> stack, to download the main ISH firmware.
>
> Signed-off-by: Rushikesh S Kadam <rushikesh.s.kadam@xxxxxxxxx>
> ---
> The patches are baselined to hid git tree, branch for-5.2/ish
> https://git.kernel.org/pub/scm/linux/kernel/git/hid/hid.git/log/?h=for-5.2/ish
>
> v3
> - Moved a couple of sanity checks from loader_cl_send() to
> process_recv().
> - Several minor changes to address review comments.
>
> v2
> - Change loader_cl_send() so that the calling function
> shall allocate and pass the buffer to be used for
> receiving firwmare response data. Corresponding changes
> in calling function and process_recv().
> - Introduced struct response_info to encapsulate and pass
> data between from the process_recv() callback to
> calling function loader_cl_send().
> - Keep count of host firmware load retries, and fail after
> 3 unsuccessful attempts.
> - Dropped report_bad_packets() function previously used for
> keeping count of bad packets.
> - Inlined loader_ish_hw_reset()'s functionality
>
> v1
> - Initial version.
>
> drivers/hid/Makefile | 1 +
> drivers/hid/intel-ish-hid/Kconfig | 15 +
> drivers/hid/intel-ish-hid/Makefile | 3 +
> drivers/hid/intel-ish-hid/ishtp-fw-loader.c | 1088 +++++++++++++++++++++++++++
> 4 files changed, 1107 insertions(+)
> create mode 100644 drivers/hid/intel-ish-hid/ishtp-fw-loader.c
>
> diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
> index 170163b..d8d393e 100644
> --- a/drivers/hid/Makefile
> +++ b/drivers/hid/Makefile
> @@ -134,3 +134,4 @@ obj-$(CONFIG_USB_KBD) += usbhid/
> obj-$(CONFIG_I2C_HID) += i2c-hid/
>
> obj-$(CONFIG_INTEL_ISH_HID) += intel-ish-hid/
> +obj-$(INTEL_ISH_FIRMWARE_DOWNLOADER) += intel-ish-hid/
> diff --git a/drivers/hid/intel-ish-hid/Kconfig b/drivers/hid/intel-ish-hid/Kconfig
> index 519e4c8..786adbc 100644
> --- a/drivers/hid/intel-ish-hid/Kconfig
> +++ b/drivers/hid/intel-ish-hid/Kconfig
> @@ -14,4 +14,19 @@ config INTEL_ISH_HID
> Broxton and Kaby Lake.
>
> Say Y here if you want to support Intel ISH. If unsure, say N.
> +
> +config INTEL_ISH_FIRMWARE_DOWNLOADER
> + tristate "Host Firmware Load feature for Intel ISH"
> + depends on INTEL_ISH_HID
> + depends on X86
> + help
> + The Integrated Sensor Hub (ISH) enables the kernel to offload
> + sensor polling and algorithm processing to a dedicated low power
> + processor in the chipset.
> +
> + The Host Firmware Load feature adds support to load the ISH
> + firmware from host file system at boot.
> +
> + Say M here if you want to support Host Firmware Loading feature
> + for Intel ISH. If unsure, say N.
> endmenu
> diff --git a/drivers/hid/intel-ish-hid/Makefile b/drivers/hid/intel-ish-hid/Makefile
> index 825b70a..2de97e4 100644
> --- a/drivers/hid/intel-ish-hid/Makefile
> +++ b/drivers/hid/intel-ish-hid/Makefile
> @@ -20,4 +20,7 @@ obj-$(CONFIG_INTEL_ISH_HID) += intel-ishtp-hid.o
> intel-ishtp-hid-objs := ishtp-hid.o
> intel-ishtp-hid-objs += ishtp-hid-client.o
>
> +obj-$(CONFIG_INTEL_ISH_FIRMWARE_DOWNLOADER) += intel-ishtp-loader.o
> +intel-ishtp-loader-objs += ishtp-fw-loader.o
> +
> ccflags-y += -Idrivers/hid/intel-ish-hid/ishtp
> diff --git a/drivers/hid/intel-ish-hid/ishtp-fw-loader.c b/drivers/hid/intel-ish-hid/ishtp-fw-loader.c
> new file mode 100644
> index 0000000..656dec0
> --- /dev/null
> +++ b/drivers/hid/intel-ish-hid/ishtp-fw-loader.c
> @@ -0,0 +1,1088 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * ISH-TP client driver for ISH firmware loading
> + *
> + * Copyright (c) 2019, Intel Corporation.
> + */
> +
> +#include <linux/firmware.h>
> +#include <linux/module.h>
> +#include <linux/pci.h>
> +#include <linux/intel-ish-client-if.h>
> +#include <linux/property.h>
> +#include <asm/cacheflush.h>
> +
> +/* Number of times we attempt to load the firmware before giving up */
> +#define MAX_LOAD_ATTEMPTS 3
> +
> +/* ISH TX/RX ring buffer pool size */
> +#define LOADER_CL_RX_RING_SIZE 1
> +#define LOADER_CL_TX_RING_SIZE 1
> +
> +/*
> + * ISH Shim firmware loader reserves 4 Kb buffer in SRAM. The buffer is
> + * used to temporarily hold the data transferred from host to Shim
> + * firmware loader. Reason for the odd size of 3968 bytes? Each IPC
> + * transfer is 128 bytes (= 4 bytes header + 124 bytes payload). So the
> + * 4 Kb buffer can hold maximum of 32 IPC transfers, which means we can
> + * have a max payload of 3968 bytes (= 32 x 124 payload).
> + */
> +#define LOADER_SHIM_IPC_BUF_SIZE 3968
> +
> +/**
> + * enum ish_loader_commands - ISH loader host commands.
> + * LOADER_CMD_XFER_QUERY Query the Shim firmware loader for
> + * capabilities
> + * LOADER_CMD_XFER_FRAGMENT Transfer one firmware image fragment at a
> + * time. The command may be executed
> + * multiple times until the entire firmware
> + * image is downloaded to SRAM.
> + * LOADER_CMD_START Start executing the main firmware.
> + */
> +enum ish_loader_commands {
> + LOADER_CMD_XFER_QUERY = 0,
> + LOADER_CMD_XFER_FRAGMENT,
> + LOADER_CMD_START,
> +};
> +
> +/* Command bit mask */
> +#define CMD_MASK GENMASK(6, 0)
> +#define IS_RESPONSE BIT(7)
> +
> +/*
> + * ISH firmware max delay for one transmit failure is 1 Hz,
> + * and firmware will retry 2 times, so 3 Hz is used for timeout.
> + */
> +#define ISHTP_SEND_TIMEOUT (3 * HZ)
> +
> +/*
> + * Loader transfer modes:
> + *
> + * LOADER_XFER_MODE_ISHTP mode uses the existing ISH-TP mechanism to
> + * transfer data. This may use IPC or DMA if supported in firmware.
> + * The buffer size is limited to 4 Kb by the IPC/ISH-TP protocol for
> + * both IPC & DMA (legacy).
> + *
> + * LOADER_XFER_MODE_DIRECT_DMA - firmware loading is a bit different
> + * from the sensor data streaming. Here we download a large (300+ Kb)
> + * image directly to ISH SRAM memory. There is limited benefit of
> + * DMA'ing 300 Kb image in 4 Kb chucks limit. Hence, we introduce
> + * this "direct dma" mode, where we do not use ISH-TP for DMA, but
> + * instead manage the DMA directly in kernel driver and Shim firmware
> + * loader (allocate buffer, break in chucks and transfer). This allows
> + * to overcome 4 Kb limit, and optimize the data flow path in firmware.
> + */
> +#define LOADER_XFER_MODE_DIRECT_DMA BIT(0)
> +#define LOADER_XFER_MODE_ISHTP BIT(1)
> +
> +/* ISH Transport Loader client unique GUID */
> +static const guid_t loader_ishtp_guid =
> + GUID_INIT(0xc804d06a, 0x55bd, 0x4ea7,
> + 0xad, 0xed, 0x1e, 0x31, 0x22, 0x8c, 0x76, 0xdc);
> +
> +#define FILENAME_SIZE 256
> +
> +/*
> + * The firmware loading latency will be minimum if we can DMA the
> + * entire ISH firmware image in one go. This requires that we allocate
> + * a large DMA buffer in kernel, which could be problematic on some
> + * platforms. So here we limit the DMA buffer size via a module_param.
> + * We default to 4 pages, but a customer can set it to higher limit if
> + * deemed appropriate for his platform.
> + */
> +static int dma_buf_size_limit = 4 * PAGE_SIZE;
> +
> +/**
> + * struct loader_msg_hdr - Header for ISH Loader commands.
> + * @command: LOADER_CMD* commands. Bit 7 is the response.
> + * @status: Command response status. Non 0, is error
> + * condition.
> + *
> + * This structure is used as header for every command/data sent/received
> + * between Host driver and ISH Shim firmware loader.
> + */
> +struct loader_msg_hdr {
> + u8 command;
> + u8 reserved[2];
> + u8 status;
> +} __packed;
> +
> +struct loader_xfer_query {
> + struct loader_msg_hdr hdr;
> + u32 image_size;
> +} __packed;
> +
> +struct ish_fw_version {
> + u16 major;
> + u16 minor;
> + u16 hotfix;
> + u16 build;
> +} __packed;
> +
> +union loader_version {
> + u32 value;
> + struct {
> + u8 major;
> + u8 minor;
> + u8 hotfix;
> + u8 build;
> + };
> +} __packed;
> +
> +struct loader_capability {
> + u32 max_fw_image_size;
> + u32 xfer_mode;
> + u32 max_dma_buf_size; /* only for dma mode, multiples of cacheline */
> +} __packed;
> +
> +struct shim_fw_info {
> + struct ish_fw_version ish_fw_version;
> + u32 protocol_version;
> + union loader_version ldr_version;
> + struct loader_capability ldr_capability;
> +} __packed;
> +
> +struct loader_xfer_query_response {
> + struct loader_msg_hdr hdr;
> + struct shim_fw_info fw_info;
> +} __packed;
> +
> +struct loader_xfer_fragment {
> + struct loader_msg_hdr hdr;
> + u32 xfer_mode;
> + u32 offset;
> + u32 size;
> + u32 is_last;
> +} __packed;
> +
> +struct loader_xfer_ipc_fragment {
> + struct loader_xfer_fragment fragment;
> + u8 data[] ____cacheline_aligned; /* variable length payload here */
> +} __packed;
> +
> +struct loader_xfer_dma_fragment {
> + struct loader_xfer_fragment fragment;
> + u64 ddr_phys_addr;
> +} __packed;
> +
> +struct loader_start {
> + struct loader_msg_hdr hdr;
> +} __packed;
> +
> +/**
> + * struct response_info - Encapsulate firmware response related
> + * information for passing between function
> + * loader_cl_send() and process_recv() callback.
> + * @data Copy the data received from firmware here.
> + * @max_size Max size allocated for the @data buffer. If the
> + * received data exceeds this value, we log an
> + * error.
> + * @size Actual size of data received from firmware.
> + * @error Returns 0 for success, negative error code for a
> + * failure in function process_recv().
> + * @received Set to true on receiving a valid firmware
> + * response to host command
> + * @wait_queue Wait queue for Host firmware loading where the
> + * client sends message to ISH firmware and waits
> + * for response
> + */
> +struct response_info {
> + void *data;
> + size_t max_size;
> + size_t size;
> + int error;
> + bool received;
> + wait_queue_head_t wait_queue;
> +};
> +
> +/**
> + * struct ishtp_cl_data - Encapsulate per ISH-TP Client Data.
> + * @work_ishtp_reset: Work queue for reset handling.
> + * @work_fw_load: Work queue for host firmware loading.
> + * @flag_retry Flag for indicating host firmware loading should
> + * be retried.
> + * @retry_count Count the number of retries.
> + *
> + * This structure is used to store data per client.
> + */
> +struct ishtp_cl_data {
> + struct ishtp_cl *loader_ishtp_cl;
> + struct ishtp_cl_device *cl_device;
> +
> + /*
> + * Used for passing firmware response information between
> + * loader_cl_send() and process_recv() callback.
> + */
> + struct response_info response;
> +
> + struct work_struct work_ishtp_reset;
> + struct work_struct work_fw_load;
> +
> + /*
> + * In certain failure scenrios, it makes sense to reset the ISH
> + * subsystem and retry Host firmware loading (e.g. bad message
> + * packet, ENOMEM, etc.). On the other hand, failures due to
> + * protocol mismatch, etc., are not recoverable. We do not
> + * retry them.
> + *
> + * If set, the flag indicates that we should re-try the
> + * particular failure.
> + */
> + bool flag_retry;
> + int retry_count;
> +};
> +
> +#define IPC_FRAGMENT_DATA_PREAMBLE \
> + offsetof(struct loader_xfer_ipc_fragment, data)
> +
> +#define cl_data_to_dev(client_data) ishtp_device((client_data)->cl_device)
> +
> +/**
> + * get_firmware_variant() - Gets the filename of firmware image to be
> + * loaded based on platform variant.
> + * @client_data Client data instance.
> + * @filename Returns firmware filename.
> + *
> + * Queries the firmware-name device property string.
> + *
> + * Return: 0 for success, negative error code for failure.
> + */
> +static int get_firmware_variant(struct ishtp_cl_data *client_data,
> + char *filename)
> +{
> + int rv;
> + const char *val;
> + struct device *devc = ishtp_get_pci_device(client_data->cl_device);
> +
> + rv = device_property_read_string(devc, "firmware-name", &val);
> + if (rv < 0) {
> + dev_err(devc,
> + "Error: ISH firmware-name device property required\n");
> + return rv;
> + }
> + return snprintf(filename, FILENAME_SIZE, "intel/%s", val);
> +}
> +
> +/**
> + * loader_cl_send() Send message from host to firmware
> + * @client_data: Client data instance
> + * @out_msg Message buffer to be sent to firmware
> + * @out_size Size of out going message
> + * @in_msg Message buffer where the incoming data copied.
> + * This buffer is allocated by calling
> + * @in_size Max size of incoming message
> + *
> + * Return: Number of bytes copied in the in_msg on success, negative
> + * error code on failure.
> + */
> +static int loader_cl_send(struct ishtp_cl_data *client_data,
> + u8 *out_msg, size_t out_size,
> + u8 *in_msg, size_t in_size)
> +{
> + int rv;
> + struct loader_msg_hdr *out_hdr = (struct loader_msg_hdr *)out_msg;
> + struct ishtp_cl *loader_ishtp_cl = client_data->loader_ishtp_cl;
> +
> + dev_dbg(cl_data_to_dev(client_data),
> + "%s: command=%02lx is_response=%u status=%02x\n",
> + __func__,
> + out_hdr->command & CMD_MASK,
> + out_hdr->command & IS_RESPONSE ? 1 : 0,
> + out_hdr->status);
> +
> + /* Setup in coming buffer & size */
> + client_data->response.data = in_msg;
> + client_data->response.max_size = in_size;
> + client_data->response.error = 0;
> + client_data->response.received = false;
> +
> + rv = ishtp_cl_send(loader_ishtp_cl, out_msg, out_size);
> + if (rv < 0) {
> + dev_err(cl_data_to_dev(client_data),
> + "ishtp_cl_send error %d\n", rv);
> + return rv;
> + }
> +
> + wait_event_interruptible_timeout(client_data->response.wait_queue,
> + client_data->response.received,
> + ISHTP_SEND_TIMEOUT);
> + if (!client_data->response.received) {
> + dev_err(cl_data_to_dev(client_data),
> + "Timed out for response to command=%02lx",
> + out_hdr->command & CMD_MASK);
> + return -ETIMEDOUT;
> + }
> +
> + if (client_data->response.error < 0)
> + return client_data->response.error;
> +
> + return client_data->response.size;
> +}
> +
> +/**
> + * process_recv() - Receive and parse incoming packet
> + * @loader_ishtp_cl: Client instance to get stats
> + * @rb_in_proc: ISH received message buffer
> + *
> + * Parse the incoming packet. If it is a response packet then it will
> + * update received and wake up the caller waiting to for the response.
> + */
> +static void process_recv(struct ishtp_cl *loader_ishtp_cl,
> + struct ishtp_cl_rb *rb_in_proc)
> +{
> + struct loader_msg_hdr *hdr;
> + size_t data_len = rb_in_proc->buf_idx;
> + struct ishtp_cl_data *client_data =
> + ishtp_get_client_data(loader_ishtp_cl);
> +
> + /*
> + * All firmware messages have a header. Check buffer size
> + * before accessing elements inside.
> + */
> + if (!rb_in_proc->buffer.data) {
> + dev_warn(cl_data_to_dev(client_data),
> + "rb_in_proc->buffer.data returned null");
> + client_data->response.error = -EBADMSG;
> + goto end_error;
> + }
> +
> + if (data_len < sizeof(struct loader_msg_hdr)) {
> + dev_err(cl_data_to_dev(client_data),
> + "data size %zu is less than header %zu\n",
> + data_len, sizeof(struct loader_msg_hdr));
> + client_data->response.error = -EMSGSIZE;
> + goto end_error;
> + }
> +
> + hdr = (struct loader_msg_hdr *)rb_in_proc->buffer.data;
> +
> + dev_dbg(cl_data_to_dev(client_data),
> + "%s: command=%02lx is_response=%u status=%02x\n",
> + __func__,
> + hdr->command & CMD_MASK,
> + hdr->command & IS_RESPONSE ? 1 : 0,
> + hdr->status);
> +
> + if (((hdr->command & CMD_MASK) != LOADER_CMD_XFER_QUERY) &&
> + ((hdr->command & CMD_MASK) != LOADER_CMD_XFER_FRAGMENT) &&
> + ((hdr->command & CMD_MASK) != LOADER_CMD_START)) {
> + dev_err(cl_data_to_dev(client_data),
> + "Invalid command=%02lx\n",
> + hdr->command & CMD_MASK);
> + client_data->response.error = -EPROTO;
> + goto end_error;
> + }
> +
> + /* Sanity check */
> + if (client_data->response.received) {
> + dev_err(cl_data_to_dev(client_data),
> + "Previous firmware message not yet processed\n");
> + client_data->response.error = -EINVAL;
> + goto end_error;
> + }
> +
> + if (!client_data->response.data) {
> + dev_err(cl_data_to_dev(client_data),
> + "Receiving buffer is null. Should be allocated by calling function\n");
> + client_data->response.error = -EINVAL;
> + goto end_error;
> + }
> +
> + if (data_len > client_data->response.max_size) {
> + dev_err(cl_data_to_dev(client_data),
> + "Received buffer size %zu is larger than allocated buffer %zu\n",
> + data_len, client_data->response.max_size);
> + client_data->response.error = -EMSGSIZE;
> + goto end_error;
> + }
> +
> + /* We expect only "response" messages from firmware */
> + if (!(hdr->command & IS_RESPONSE)) {
> + dev_err(cl_data_to_dev(client_data),
> + "Invalid response to command\n");
> + client_data->response.error = -EIO;
> + goto end_error;
> + }
> +
> + if (hdr->status) {
> + dev_err(cl_data_to_dev(client_data),
> + "Loader returned status %d\n",
> + hdr->status);
> + client_data->response.error = -EIO;
> + goto end_error;
> + }
> +
> + /* Update the actual received buffer size */
> + client_data->response.size = data_len;
> +
> + /*
> + * Copy the buffer received in firmware response for the
> + * calling thread.
> + */
> + memcpy(client_data->response.data,
> + rb_in_proc->buffer.data, data_len);
> +
> + /* Free the buffer */
> + ishtp_cl_io_rb_recycle(rb_in_proc);
> + rb_in_proc = NULL;
> +
> + /* Wake the calling thread */
> + client_data->response.received = true;
> + wake_up_interruptible(&client_data->response.wait_queue);
> +
> +end_error:
> + /* Free the buffer if we did not do above */
> + if (rb_in_proc)
> + ishtp_cl_io_rb_recycle(rb_in_proc);
> +}
> +
> +/**
> + * loader_cl_event_cb() - bus driver callback for incoming message
> + * @device: Pointer to the ishtp client device for which this
> + * message is targeted
> + *
> + * Remove the packet from the list and process the message by calling
> + * process_recv
> + */
> +static void loader_cl_event_cb(struct ishtp_cl_device *cl_device)
> +{
> + struct ishtp_cl_rb *rb_in_proc;
> + struct ishtp_cl *loader_ishtp_cl = ishtp_get_drvdata(cl_device);
> +
> + while ((rb_in_proc = ishtp_cl_rx_get_rb(loader_ishtp_cl)) != NULL) {
> + /* Process the data packet from firmware */
> + process_recv(loader_ishtp_cl, rb_in_proc);
> + }
> +}
> +
> +/**
> + * ish_query_loader_prop() - Query ISH Shim firmware loader
> + * @client_data: Client data instance
> + * @fw: Poiner to firmware data struct in host memory
> + * @fw_info: Loader firmware properties
> + *
> + * This function queries the ISH Shim firmware loader for capabilities.
> + *
> + * Return: 0 for success, negative error code for failure.
> + */
> +static int ish_query_loader_prop(struct ishtp_cl_data *client_data,
> + const struct firmware *fw,
> + struct shim_fw_info *fw_info)
> +{
> + int rv;
> + struct loader_xfer_query ldr_xfer_query;
> + struct loader_xfer_query_response ldr_xfer_query_resp;
> +
> + memset(&ldr_xfer_query, 0, sizeof(ldr_xfer_query));
> + ldr_xfer_query.hdr.command = LOADER_CMD_XFER_QUERY;
> + ldr_xfer_query.image_size = fw->size;
> + rv = loader_cl_send(client_data,
> + (u8 *)&ldr_xfer_query,
> + sizeof(ldr_xfer_query),
> + (u8 *)&ldr_xfer_query_resp,
> + sizeof(ldr_xfer_query_resp));
> + if (rv < 0) {
> + client_data->flag_retry = true;
> + return rv;
> + }
> +
> + /* On success, the return value is the received buffer size */
> + if (rv != sizeof(struct loader_xfer_query_response)) {
> + dev_err(cl_data_to_dev(client_data),
> + "data size %d is not equal to size of loader_xfer_query_response %zu\n",
> + rv, sizeof(struct loader_xfer_query_response));
> + client_data->flag_retry = true;
> + return -EMSGSIZE;
> + }
> +
> + /* Save fw_info for use outside this function */
> + *fw_info = ldr_xfer_query_resp.fw_info;
> +
> + /* Loader firmware properties */
> + dev_dbg(cl_data_to_dev(client_data),
> + "ish_fw_version: major=%d minor=%d hotfix=%d build=%d protocol_version=0x%x loader_version=%d\n",
> + fw_info->ish_fw_version.major,
> + fw_info->ish_fw_version.minor,
> + fw_info->ish_fw_version.hotfix,
> + fw_info->ish_fw_version.build,
> + fw_info->protocol_version,
> + fw_info->ldr_version.value);
> +
> + dev_dbg(cl_data_to_dev(client_data),
> + "loader_capability: max_fw_image_size=0x%x xfer_mode=%d max_dma_buf_size=0x%x dma_buf_size_limit=0x%x\n",
> + fw_info->ldr_capability.max_fw_image_size,
> + fw_info->ldr_capability.xfer_mode,
> + fw_info->ldr_capability.max_dma_buf_size,
> + dma_buf_size_limit);
> +
> + /* Sanity checks */
> + if (fw_info->ldr_capability.max_fw_image_size < fw->size) {
> + dev_err(cl_data_to_dev(client_data),
> + "ISH firmware size %zu is greater than Shim firmware loader max supported %d\n",
> + fw->size,
> + fw_info->ldr_capability.max_fw_image_size);
> + return -ENOSPC;
> + }
> +
> + /* For DMA the buffer size should be multiple of cacheline size */
> + if ((fw_info->ldr_capability.xfer_mode & LOADER_XFER_MODE_DIRECT_DMA) &&
> + (fw_info->ldr_capability.max_dma_buf_size % L1_CACHE_BYTES)) {
> + dev_err(cl_data_to_dev(client_data),
> + "Shim firmware loader buffer size %d should be multipe of cacheline\n",
> + fw_info->ldr_capability.max_dma_buf_size);
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> +/**
> + * ish_fw_xfer_ishtp() Loads ISH firmware using ishtp interface
> + * @client_data: Client data instance
> + * @fw: Pointer to firmware data struct in host memory
> + *
> + * This function uses ISH-TP to transfer ISH firmware from host to
> + * ISH SRAM. Lower layers may use IPC or DMA depending on firmware
> + * support.
> + *
> + * Return: 0 for success, negative error code for failure.
> + */
> +static int ish_fw_xfer_ishtp(struct ishtp_cl_data *client_data,
> + const struct firmware *fw)
> +{
> + int rv;
> + u32 fragment_offset, fragment_size, payload_max_size;
> + struct loader_xfer_ipc_fragment *ldr_xfer_ipc_frag;
> + struct loader_msg_hdr ldr_xfer_ipc_ack;
> +
> + payload_max_size =
> + LOADER_SHIM_IPC_BUF_SIZE - IPC_FRAGMENT_DATA_PREAMBLE;
> +
> + ldr_xfer_ipc_frag = kzalloc(LOADER_SHIM_IPC_BUF_SIZE, GFP_KERNEL);
> + if (!ldr_xfer_ipc_frag) {

Log error here.

> + client_data->flag_retry = true;
> + return -ENOMEM;
> + }
> +
> + ldr_xfer_ipc_frag->fragment.hdr.command = LOADER_CMD_XFER_FRAGMENT;
> + ldr_xfer_ipc_frag->fragment.xfer_mode = LOADER_XFER_MODE_ISHTP;
> +
> + /* Break the firmware image into fragments and send as ISH-TP payload */
> + fragment_offset = 0;
> + while (fragment_offset < fw->size) {
> + if (fragment_offset + payload_max_size < fw->size) {
> + fragment_size = payload_max_size;
> + ldr_xfer_ipc_frag->fragment.is_last = 0;
> + } else {
> + fragment_size = fw->size - fragment_offset;
> + ldr_xfer_ipc_frag->fragment.is_last = 1;
> + }
> +
> + ldr_xfer_ipc_frag->fragment.offset = fragment_offset;
> + ldr_xfer_ipc_frag->fragment.size = fragment_size;
> + memcpy(ldr_xfer_ipc_frag->data,
> + &fw->data[fragment_offset],
> + fragment_size);
> +
> + dev_dbg(cl_data_to_dev(client_data),
> + "xfer_mode=ipc offset=0x%08x size=0x%08x is_last=%d\n",
> + ldr_xfer_ipc_frag->fragment.offset,
> + ldr_xfer_ipc_frag->fragment.size,
> + ldr_xfer_ipc_frag->fragment.is_last);
> +
> + rv = loader_cl_send(client_data,
> + (u8 *)ldr_xfer_ipc_frag,
> + IPC_FRAGMENT_DATA_PREAMBLE + fragment_size,
> + (u8 *)&ldr_xfer_ipc_ack,
> + sizeof(ldr_xfer_ipc_ack));
> + if (rv < 0) {
> + client_data->flag_retry = true;
> + goto end_err_resp_buf_release;
> + }
> +
> + fragment_offset += fragment_size;
> + }
> +
> + kfree(ldr_xfer_ipc_frag);
> + return 0;
> +
> +end_err_resp_buf_release:
> + /* Free ISH buffer if not done already, in error case */
> + kfree(ldr_xfer_ipc_frag);
> + return rv;
> +}
> +
> +/**
> + * ish_fw_xfer_direct_dma() - Loads ISH firmware using direct dma
> + * @client_data: Client data instance
> + * @fw: Pointer to firmware data struct in host memory
> + * @fw_info: Loader firmware properties
> + *
> + * Host firmware load is a unique case where we need to download
> + * a large firmware image (200+ Kb). This function implements
> + * direct DMA transfer in kernel and ISH firmware. This allows
> + * us to overcome the ISH-TP 4 Kb limit, and allows us to DMA
> + * directly to ISH UMA at location of choice.
> + * Function depends on corresponding support in ISH firmware.
> + *
> + * Return: 0 for success, negative error code for failure.
> + */
> +static int ish_fw_xfer_direct_dma(struct ishtp_cl_data *client_data,
> + const struct firmware *fw,
> + const struct shim_fw_info fw_info)
> +{
> + int rv;
> + void *dma_buf;
> + dma_addr_t dma_buf_phy;
> + u32 fragment_offset, fragment_size, payload_max_size;
> + struct loader_msg_hdr ldr_xfer_dma_frag_ack;
> + struct loader_xfer_dma_fragment ldr_xfer_dma_frag;
> + struct device *devc = ishtp_get_pci_device(client_data->cl_device);
> + u32 shim_fw_buf_size =
> + fw_info.ldr_capability.max_dma_buf_size;
> +
> + /*
> + * payload_max_size should be set to minimum of
> + * (1) Size of firmware to be loaded,
> + * (2) Max DMA buffer size supported by Shim firmware,
> + * (3) DMA buffer size limit set by boot_param dma_buf_size_limit.
> + */
> + payload_max_size = min3(fw->size,
> + (size_t)shim_fw_buf_size,
> + (size_t)dma_buf_size_limit);
> +
> + /*
> + * Buffer size should be multiple of cacheline size
> + * if it's not, select the previous cacheline boundary.
> + */
> + payload_max_size &= ~(L1_CACHE_BYTES - 1);
> +
> + dma_buf = kmalloc(payload_max_size, GFP_KERNEL | GFP_DMA32);
> + if (!dma_buf) {

Log error here.

> + client_data->flag_retry = true;
> + return -ENOMEM;
> + }
> +
> + dma_buf_phy = dma_map_single(devc, dma_buf, payload_max_size,
> + DMA_TO_DEVICE);
> + if (dma_mapping_error(devc, dma_buf_phy)) {
> + dev_err(cl_data_to_dev(client_data), "DMA map failed\n");
> + client_data->flag_retry = true;
> + rv = -ENOMEM;
> + goto end_err_dma_buf_release;
> + }
> +
> + ldr_xfer_dma_frag.fragment.hdr.command = LOADER_CMD_XFER_FRAGMENT;
> + ldr_xfer_dma_frag.fragment.xfer_mode = LOADER_XFER_MODE_DIRECT_DMA;
> + ldr_xfer_dma_frag.ddr_phys_addr = (u64)dma_buf_phy;
> +
> + /* Send the firmware image in chucks of payload_max_size */
> + fragment_offset = 0;
> + while (fragment_offset < fw->size) {
> + if (fragment_offset + payload_max_size < fw->size) {
> + fragment_size = payload_max_size;
> + ldr_xfer_dma_frag.fragment.is_last = 0;
> + } else {
> + fragment_size = fw->size - fragment_offset;
> + ldr_xfer_dma_frag.fragment.is_last = 1;
> + }
> +
> + ldr_xfer_dma_frag.fragment.offset = fragment_offset;
> + ldr_xfer_dma_frag.fragment.size = fragment_size;
> + memcpy(dma_buf, &fw->data[fragment_offset], fragment_size);
> +
> + dma_sync_single_for_device(devc, dma_buf_phy,
> + payload_max_size,
> + DMA_TO_DEVICE);
> +
> + /*
> + * Flush cache here because the dma_sync_single_for_device()
> + * does not do for x86.
> + */
> + clflush_cache_range(dma_buf, payload_max_size);
> +
> + dev_dbg(cl_data_to_dev(client_data),
> + "xfer_mode=dma offset=0x%08x size=0x%x is_last=%d ddr_phys_addr=0x%016llx\n",
> + ldr_xfer_dma_frag.fragment.offset,
> + ldr_xfer_dma_frag.fragment.size,
> + ldr_xfer_dma_frag.fragment.is_last,
> + ldr_xfer_dma_frag.ddr_phys_addr);
> +
> + rv = loader_cl_send(client_data,
> + (u8 *)&ldr_xfer_dma_frag,
> + sizeof(ldr_xfer_dma_frag),
> + (u8 *)&ldr_xfer_dma_frag_ack,
> + sizeof(ldr_xfer_dma_frag_ack));
> + if (rv < 0) {
> + client_data->flag_retry = true;
> + goto end_err_resp_buf_release;
> + }
> +
> + fragment_offset += fragment_size;
> + }
> +
> + dma_unmap_single(devc, dma_buf_phy, payload_max_size, DMA_TO_DEVICE);
> + kfree(dma_buf);
> + return 0;
> +
> +end_err_resp_buf_release:
> + /* Free ISH buffer if not done already, in error case */
> + dma_unmap_single(devc, dma_buf_phy, payload_max_size, DMA_TO_DEVICE);
> +end_err_dma_buf_release:
> + kfree(dma_buf);
> + return rv;
> +}
> +
> +/**
> + * ish_fw_start() Start executing ISH main firmware
> + * @client_data: client data instance
> + *
> + * This function sends message to Shim firmware loader to start
> + * the execution of ISH main firmware.
> + *
> + * Return: 0 for success, negative error code for failure.
> + */
> +static int ish_fw_start(struct ishtp_cl_data *client_data)
> +{
> + struct loader_start ldr_start;
> + struct loader_msg_hdr ldr_start_ack;
> +
> + memset(&ldr_start, 0, sizeof(ldr_start));
> + ldr_start.hdr.command = LOADER_CMD_START;
> + return loader_cl_send(client_data,
> + (u8 *)&ldr_start,
> + sizeof(ldr_start),
> + (u8 *)&ldr_start_ack,
> + sizeof(ldr_start_ack));
> +}
> +
> +/**
> + * load_fw_from_host() Loads ISH firmware from host
> + * @client_data: Client data instance
> + *
> + * This function loads the ISH firmware to ISH SRAM and starts execution
> + *
> + * Return: 0 for success, negative error code for failure.
> + */
> +static int load_fw_from_host(struct ishtp_cl_data *client_data)
> +{
> + int rv;
> + u32 xfer_mode;
> + char *filename;
> + const struct firmware *fw;
> + struct shim_fw_info fw_info;
> + struct ishtp_cl *loader_ishtp_cl = client_data->loader_ishtp_cl;
> +
> + client_data->flag_retry = false;
> +
> + filename = kzalloc(FILENAME_SIZE, GFP_KERNEL);
> + if (!filename) {
> + client_data->flag_retry = true;
> + rv = -ENOMEM;

log error here

> + goto end_error;
> + }
> +
> + /* Get filename of the ISH firmware to be loaded */
> + rv = get_firmware_variant(client_data, filename);
> + if (rv < 0)
> + goto end_err_filename_buf_release;
> +
> + rv = request_firmware(&fw, filename, cl_data_to_dev(client_data));
> + if (rv < 0)
> + goto end_err_filename_buf_release;
> +
> + /* Step 1: Query Shim firmware loader properties */
> +
> + rv = ish_query_loader_prop(client_data, fw, &fw_info);
> + if (rv < 0)
> + goto end_err_fw_release;
> +
> + /* Step 2: Send the main firmware image to be loaded, to ISH SRAM */
> +
> + xfer_mode = fw_info.ldr_capability.xfer_mode;
> + if (xfer_mode & LOADER_XFER_MODE_DIRECT_DMA) {
> + rv = ish_fw_xfer_direct_dma(client_data, fw, fw_info);
> + } else if (xfer_mode & LOADER_XFER_MODE_ISHTP) {
> + rv = ish_fw_xfer_ishtp(client_data, fw);
> + } else {
> + dev_err(cl_data_to_dev(client_data),
> + "No transfer mode selected in firmware\n");
> + rv = -EINVAL;
> + }
> + if (rv < 0)
> + goto end_err_fw_release;
> +
> + /* Step 3: Start ISH main firmware exeuction */
> +
> + rv = ish_fw_start(client_data);
> + if (rv < 0)
> + goto end_err_fw_release;
> +
> + release_firmware(fw);
> + kfree(filename);
> + dev_info(cl_data_to_dev(client_data), "ISH firmware %s loaded\n",
> + filename);
> + return 0;
> +
> +end_err_fw_release:
> + release_firmware(fw);
> +end_err_filename_buf_release:
> + kfree(filename);
> +end_error:
> + /* Keep a count of retries, and give up after 3 attempts */
> + if (client_data->flag_retry &&
> + client_data->retry_count++ < MAX_LOAD_ATTEMPTS) {
> + dev_warn(cl_data_to_dev(client_data),
> + "ISH host firmware load failed %d. Resetting ISH, and trying again..\n",
> + rv);
> + ish_hw_reset(ishtp_get_ishtp_device(loader_ishtp_cl));
> + } else {
> + dev_err(cl_data_to_dev(client_data),
> + "ISH host firmware load failed %d\n", rv);
> + }
> + return rv;
> +}
> +
> +static void load_fw_from_host_handler(struct work_struct *work)
> +{
> + struct ishtp_cl_data *client_data;
> +
> + client_data = container_of(work, struct ishtp_cl_data,
> + work_fw_load);
> + load_fw_from_host(client_data);
> +}
> +
> +/**
> + * loader_init() - Init function for ISH-TP client
> + * @loader_ishtp_cl: ISH-TP client instance
> + * @reset: true if called for init after reset
> + *
> + * Return: 0 for success, negative error code for failure
> + */
> +static int loader_init(struct ishtp_cl *loader_ishtp_cl, int reset)
> +{
> + int rv;
> + struct ishtp_fw_client *fw_client;
> + struct ishtp_cl_data *client_data =
> + ishtp_get_client_data(loader_ishtp_cl);
> +
> + dev_dbg(cl_data_to_dev(client_data), "reset flag: %d\n", reset);
> +
> + rv = ishtp_cl_link(loader_ishtp_cl);
> + if (rv < 0) {
> + dev_err(cl_data_to_dev(client_data), "ishtp_cl_link failed\n");
> + return rv;
> + }
> +
> + /* Connect to firmware client */
> + ishtp_set_tx_ring_size(loader_ishtp_cl, LOADER_CL_TX_RING_SIZE);
> + ishtp_set_rx_ring_size(loader_ishtp_cl, LOADER_CL_RX_RING_SIZE);
> +
> + fw_client =
> + ishtp_fw_cl_get_client(ishtp_get_ishtp_device(loader_ishtp_cl),
> + &loader_ishtp_guid);
> + if (!fw_client) {
> + dev_err(cl_data_to_dev(client_data),
> + "ISH client uuid not found\n");
> + rv = -ENOENT;
> + goto err_cl_unlink;
> + }
> +
> + ishtp_cl_set_fw_client_id(loader_ishtp_cl,
> + ishtp_get_fw_client_id(fw_client));
> + ishtp_set_connection_state(loader_ishtp_cl, ISHTP_CL_CONNECTING);
> +
> + rv = ishtp_cl_connect(loader_ishtp_cl);
> + if (rv < 0) {
> + dev_err(cl_data_to_dev(client_data), "Client connect fail\n");
> + goto err_cl_unlink;
> + }
> +
> + dev_dbg(cl_data_to_dev(client_data), "Client connected\n");
> +
> + ishtp_register_event_cb(client_data->cl_device, loader_cl_event_cb);
> +
> + return 0;
> +
> +err_cl_unlink:
> + ishtp_cl_unlink(loader_ishtp_cl);
> + return rv;
> +}
> +
> +static void loader_deinit(struct ishtp_cl *loader_ishtp_cl)
> +{
> + ishtp_set_connection_state(loader_ishtp_cl, ISHTP_CL_DISCONNECTING);
> + ishtp_cl_disconnect(loader_ishtp_cl);
> + ishtp_cl_unlink(loader_ishtp_cl);
> + ishtp_cl_flush_queues(loader_ishtp_cl);
> +
> + /* Disband and free all Tx and Rx client-level rings */
> + ishtp_cl_free(loader_ishtp_cl);
> +}
> +
> +static void reset_handler(struct work_struct *work)
> +{
> + int rv;
> + struct ishtp_cl_data *client_data;
> + struct ishtp_cl *loader_ishtp_cl;
> + struct ishtp_cl_device *cl_device;
> +
> + client_data = container_of(work, struct ishtp_cl_data,
> + work_ishtp_reset);
> +
> + loader_ishtp_cl = client_data->loader_ishtp_cl;
> + cl_device = client_data->cl_device;
> +
> + /* Unlink, flush queues & start again */
> + ishtp_cl_unlink(loader_ishtp_cl);
> + ishtp_cl_flush_queues(loader_ishtp_cl);
> + ishtp_cl_free(loader_ishtp_cl);
> +
> + loader_ishtp_cl = ishtp_cl_allocate(cl_device);
> + if (!loader_ishtp_cl)
> + return;
> +
> + ishtp_set_drvdata(cl_device, loader_ishtp_cl);
> + ishtp_set_client_data(loader_ishtp_cl, client_data);
> + client_data->loader_ishtp_cl = loader_ishtp_cl;
> + client_data->cl_device = cl_device;
> +
> + rv = loader_init(loader_ishtp_cl, 1);
> + if (rv < 0) {
> + dev_err(ishtp_device(cl_device), "Reset Failed\n");
> + return;
> + }
> +
> + /* ISH firmware loading from host */
> + load_fw_from_host(client_data);
> +}
> +
> +/**
> + * loader_ishtp_cl_probe() - ISH-TP client driver probe
> + * @cl_device: ISH-TP client device instance
> + *
> + * This function gets called on device create on ISH-TP bus
> + *
> + * Return: 0 for success, negative error code for failure
> + */
> +static int loader_ishtp_cl_probe(struct ishtp_cl_device *cl_device)
> +{
> + struct ishtp_cl *loader_ishtp_cl;
> + struct ishtp_cl_data *client_data;
> + int rv;
> +
> + client_data = devm_kzalloc(ishtp_device(cl_device),
> + sizeof(*client_data),
> + GFP_KERNEL);
> + if (!client_data)

log error here

> + return -ENOMEM;
> +
> + loader_ishtp_cl = ishtp_cl_allocate(cl_device);
> + if (!loader_ishtp_cl)

log error here

> + return -ENOMEM;
> +
> + ishtp_set_drvdata(cl_device, loader_ishtp_cl);
> + ishtp_set_client_data(loader_ishtp_cl, client_data);
> + client_data->loader_ishtp_cl = loader_ishtp_cl;
> + client_data->cl_device = cl_device;
> +
> + init_waitqueue_head(&client_data->response.wait_queue);
> +
> + INIT_WORK(&client_data->work_ishtp_reset,
> + reset_handler);
> + INIT_WORK(&client_data->work_fw_load,
> + load_fw_from_host_handler);
> +
> + rv = loader_init(loader_ishtp_cl, 0);
> + if (rv < 0) {
> + ishtp_cl_free(loader_ishtp_cl);
> + return rv;
> + }
> + ishtp_get_device(cl_device);
> +
> + client_data->retry_count = 0;
> +
> + /* ISH firmware loading from host */
> + schedule_work(&client_data->work_fw_load);
> +
> + return 0;
> +}
> +
> +/**
> + * loader_ishtp_cl_remove() - ISH-TP client driver remove
> + * @cl_device: ISH-TP client device instance
> + *
> + * This function gets called on device remove on ISH-TP bus
> + *
> + * Return: 0
> + */
> +static int loader_ishtp_cl_remove(struct ishtp_cl_device *cl_device)
> +{
> + struct ishtp_cl_data *client_data;
> + struct ishtp_cl *loader_ishtp_cl = ishtp_get_drvdata(cl_device);
> +
> + client_data = ishtp_get_client_data(loader_ishtp_cl);
> +
> + /*
> + * The sequence of the following two cancel_work_sync() is
> + * important. The work_fw_load can in turn schedue
> + * work_ishtp_reset, so first cancel work_fw_load then
> + * cancel work_ishtp_reset.
> + */
> + cancel_work_sync(&client_data->work_fw_load);
> + cancel_work_sync(&client_data->work_ishtp_reset);
> + loader_deinit(loader_ishtp_cl);
> + ishtp_put_device(cl_device);
> +
> + return 0;
> +}
> +
> +/**
> + * loader_ishtp_cl_reset() - ISH-TP client driver reset
> + * @cl_device: ISH-TP client device instance
> + *
> + * This function gets called on device reset on ISH-TP bus
> + *
> + * Return: 0
> + */
> +static int loader_ishtp_cl_reset(struct ishtp_cl_device *cl_device)
> +{
> + struct ishtp_cl_data *client_data;
> + struct ishtp_cl *loader_ishtp_cl = ishtp_get_drvdata(cl_device);
> +
> + client_data = ishtp_get_client_data(loader_ishtp_cl);
> +
> + schedule_work(&client_data->work_ishtp_reset);
> +
> + return 0;
> +}
> +
> +static struct ishtp_cl_driver loader_ishtp_cl_driver = {
> + .name = "ish-loader",
> + .guid = &loader_ishtp_guid,
> + .probe = loader_ishtp_cl_probe,
> + .remove = loader_ishtp_cl_remove,
> + .reset = loader_ishtp_cl_reset,
> +};
> +
> +static int __init ish_loader_init(void)
> +{
> + return ishtp_cl_driver_register(&loader_ishtp_cl_driver, THIS_MODULE);
> +}
> +
> +static void __exit ish_loader_exit(void)
> +{
> + ishtp_cl_driver_unregister(&loader_ishtp_cl_driver);
> +}
> +
> +late_initcall(ish_loader_init);
> +module_exit(ish_loader_exit);
> +
> +module_param(dma_buf_size_limit, int, 0644);
> +MODULE_PARM_DESC(dma_buf_size_limit, "Limit the DMA buf size to this value in bytes");
> +
> +MODULE_DESCRIPTION("ISH ISH-TP Host firmware Loader Client Driver");
> +MODULE_AUTHOR("Rushikesh S Kadam <rushikesh.s.kadam@xxxxxxxxx>");
> +
> +MODULE_LICENSE("GPL v2");
> +MODULE_ALIAS("ishtp:*");
> --
> 1.9.1
>