Commit f4f71536 authored by Simon Glass's avatar Simon Glass
Browse files

dm: usb: sandbox: Add an emulator for USB flash devices



This emulator supports USB enumeration and allows a local file to be provided
as the contents of the emulated flash stick. U-Boot can then use the file as
it would a normal device, with all access passing through the usb_stor layer
and the USB stack.
Signed-off-by: default avatarSimon Glass <sjg@chromium.org>
Reviewed-by: default avatarMarek Vasut <marex@denx.de>
parent 095fdef0
......@@ -5,4 +5,5 @@
# SPDX-License-Identifier: GPL-2.0+
#
obj-$(CONFIG_USB_EMUL) += sandbox_flash.o
obj-$(CONFIG_USB_EMUL) += usb-emul-uclass.o
/*
* (C) Copyright 2015 Google, Inc
* Written by Simon Glass <sjg@chromium.org>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <dm.h>
#include <os.h>
#include <scsi.h>
#include <usb.h>
DECLARE_GLOBAL_DATA_PTR;
/*
* This driver emulates a flash stick using the UFI command specification and
* the BBB (bulk/bulk/bulk) protocol. It supports only a single logical unit
* number (LUN 0).
*/
enum {
SANDBOX_FLASH_EP_OUT = 1, /* endpoints */
SANDBOX_FLASH_EP_IN = 2,
SANDBOX_FLASH_BLOCK_LEN = 512,
};
enum cmd_phase {
PHASE_START,
PHASE_DATA,
PHASE_STATUS,
};
/**
* struct sandbox_flash_priv - private state for this driver
*
* @error: true if there is an error condition
* @alloc_len: Allocation length from the last incoming command
* @transfer_len: Transfer length from CBW header
* @read_len: Number of blocks of data left in the current read command
* @tag: Tag value from last command
* @fd: File descriptor of backing file
* @file_size: Size of file in bytes
* @status_buff: Data buffer for outgoing status
* @buff_used: Number of bytes ready to transfer back to host
* @buff: Data buffer for outgoing data
*/
struct sandbox_flash_priv {
bool error;
int alloc_len;
int transfer_len;
int read_len;
enum cmd_phase phase;
u32 tag;
int fd;
loff_t file_size;
struct umass_bbb_csw status;
int buff_used;
u8 buff[512];
};
struct sandbox_flash_plat {
const char *pathname;
};
struct scsi_inquiry_resp {
u8 type;
u8 flags;
u8 version;
u8 data_format;
u8 additional_len;
u8 spare[3];
char vendor[8];
char product[16];
char revision[4];
};
struct scsi_read_capacity_resp {
u32 last_block_addr;
u32 block_len;
};
struct __packed scsi_read10_req {
u8 cmd;
u8 lun_flags;
u32 lba;
u8 spare;
u16 transfer_len;
u8 spare2[3];
};
enum {
STRINGID_MANUFACTURER = 1,
STRINGID_PRODUCT,
STRINGID_SERIAL,
STRINGID_COUNT,
};
static struct usb_string flash_strings[] = {
{STRINGID_MANUFACTURER, "sandbox"},
{STRINGID_PRODUCT, "flash"},
{STRINGID_SERIAL, "2345"},
{},
};
static struct usb_device_descriptor flash_device_desc = {
.bLength = sizeof(flash_device_desc),
.bDescriptorType = USB_DT_DEVICE,
.bcdUSB = __constant_cpu_to_le16(0x0200),
.bDeviceClass = 0,
.bDeviceSubClass = 0,
.bDeviceProtocol = 0,
.idVendor = __constant_cpu_to_le16(0x1234),
.idProduct = __constant_cpu_to_le16(0x5678),
.iManufacturer = STRINGID_MANUFACTURER,
.iProduct = STRINGID_PRODUCT,
.iSerialNumber = STRINGID_SERIAL,
.bNumConfigurations = 1,
};
static struct usb_config_descriptor flash_config0 = {
.bLength = sizeof(flash_config0),
.bDescriptorType = USB_DT_CONFIG,
/* wTotalLength is set up by usb-emul-uclass */
.bNumInterfaces = 1,
.bConfigurationValue = 0,
.iConfiguration = 0,
.bmAttributes = 1 << 7,
.bMaxPower = 50,
};
static struct usb_interface_descriptor flash_interface0 = {
.bLength = sizeof(flash_interface0),
.bDescriptorType = USB_DT_INTERFACE,
.bInterfaceNumber = 0,
.bAlternateSetting = 0,
.bNumEndpoints = 2,
.bInterfaceClass = USB_CLASS_MASS_STORAGE,
.bInterfaceSubClass = US_SC_UFI,
.bInterfaceProtocol = US_PR_BULK,
.iInterface = 0,
};
static struct usb_endpoint_descriptor flash_endpoint0_out = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = SANDBOX_FLASH_EP_OUT,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = __constant_cpu_to_le16(1024),
.bInterval = 0,
};
static struct usb_endpoint_descriptor flash_endpoint1_in = {
.bLength = USB_DT_ENDPOINT_SIZE,
.bDescriptorType = USB_DT_ENDPOINT,
.bEndpointAddress = SANDBOX_FLASH_EP_IN | USB_ENDPOINT_DIR_MASK,
.bmAttributes = USB_ENDPOINT_XFER_BULK,
.wMaxPacketSize = __constant_cpu_to_le16(1024),
.bInterval = 0,
};
static void *flash_desc_list[] = {
&flash_device_desc,
&flash_config0,
&flash_interface0,
&flash_endpoint0_out,
&flash_endpoint1_in,
NULL,
};
static int sandbox_flash_control(struct udevice *dev, struct usb_device *udev,
unsigned long pipe, void *buff, int len,
struct devrequest *setup)
{
struct sandbox_flash_priv *priv = dev_get_priv(dev);
if (pipe == usb_rcvctrlpipe(udev, 0)) {
switch (setup->request) {
case US_BBB_RESET:
priv->error = false;
return 0;
case US_BBB_GET_MAX_LUN:
*(char *)buff = '\0';
return 1;
default:
debug("request=%x\n", setup->request);
break;
}
}
debug("pipe=%lx\n", pipe);
return -EIO;
}
static void setup_fail_response(struct sandbox_flash_priv *priv)
{
struct umass_bbb_csw *csw = &priv->status;
csw->dCSWSignature = CSWSIGNATURE;
csw->dCSWTag = priv->tag;
csw->dCSWDataResidue = 0;
csw->bCSWStatus = CSWSTATUS_FAILED;
priv->buff_used = 0;
}
/**
* setup_response() - set up a response to send back to the host
*
* @priv: Sandbox flash private data
* @resp: Response to send, or NULL if none
* @size: Size of response
*/
static void setup_response(struct sandbox_flash_priv *priv, void *resp,
int size)
{
struct umass_bbb_csw *csw = &priv->status;
csw->dCSWSignature = CSWSIGNATURE;
csw->dCSWTag = priv->tag;
csw->dCSWDataResidue = 0;
csw->bCSWStatus = CSWSTATUS_GOOD;
assert(!resp || resp == priv->buff);
priv->buff_used = size;
}
static void handle_read(struct sandbox_flash_priv *priv, ulong lba,
ulong transfer_len)
{
debug("%s: lba=%lx, transfer_len=%lx\n", __func__, lba, transfer_len);
if (priv->fd != -1) {
os_lseek(priv->fd, lba * SANDBOX_FLASH_BLOCK_LEN, OS_SEEK_SET);
priv->read_len = transfer_len;
setup_response(priv, priv->buff,
transfer_len * SANDBOX_FLASH_BLOCK_LEN);
} else {
setup_fail_response(priv);
}
}
static int handle_ufi_command(struct sandbox_flash_priv *priv, const void *buff,
int len)
{
const struct SCSI_cmd_block *req = buff;
switch (*req->cmd) {
case SCSI_INQUIRY: {
struct scsi_inquiry_resp *resp = (void *)priv->buff;
priv->alloc_len = req->cmd[4];
memset(resp, '\0', sizeof(*resp));
resp->data_format = 1;
resp->additional_len = 0x1f;
strncpy(resp->vendor,
flash_strings[STRINGID_MANUFACTURER - 1].s,
sizeof(resp->vendor));
strncpy(resp->product, flash_strings[STRINGID_PRODUCT - 1].s,
sizeof(resp->product));
strncpy(resp->revision, "1.0", sizeof(resp->revision));
setup_response(priv, resp, sizeof(*resp));
break;
}
case SCSI_TST_U_RDY:
setup_response(priv, NULL, 0);
break;
case SCSI_RD_CAPAC: {
struct scsi_read_capacity_resp *resp = (void *)priv->buff;
uint blocks;
if (priv->file_size)
blocks = priv->file_size / SANDBOX_FLASH_BLOCK_LEN - 1;
else
blocks = 0;
resp->last_block_addr = cpu_to_be32(blocks);
resp->block_len = cpu_to_be32(SANDBOX_FLASH_BLOCK_LEN);
setup_response(priv, resp, sizeof(*resp));
break;
}
case SCSI_READ10: {
struct scsi_read10_req *req = (void *)buff;
handle_read(priv, be32_to_cpu(req->lba),
be16_to_cpu(req->transfer_len));
break;
}
default:
debug("Command not supported: %x\n", req->cmd[0]);
return -EPROTONOSUPPORT;
}
priv->phase = priv->transfer_len ? PHASE_DATA : PHASE_STATUS;
return 0;
}
static int sandbox_flash_bulk(struct udevice *dev, struct usb_device *udev,
unsigned long pipe, void *buff, int len)
{
struct sandbox_flash_priv *priv = dev_get_priv(dev);
int ep = usb_pipeendpoint(pipe);
struct umass_bbb_cbw *cbw = buff;
debug("%s: dev=%s, pipe=%lx, ep=%x, len=%x, phase=%d\n", __func__,
dev->name, pipe, ep, len, priv->phase);
switch (ep) {
case SANDBOX_FLASH_EP_OUT:
switch (priv->phase) {
case PHASE_START:
priv->alloc_len = 0;
priv->read_len = 0;
if (priv->error || len != UMASS_BBB_CBW_SIZE ||
cbw->dCBWSignature != CBWSIGNATURE)
goto err;
if ((cbw->bCBWFlags & CBWFLAGS_SBZ) ||
cbw->bCBWLUN != 0)
goto err;
if (cbw->bCDBLength < 1 || cbw->bCDBLength >= 0x10)
goto err;
priv->transfer_len = cbw->dCBWDataTransferLength;
priv->tag = cbw->dCBWTag;
return handle_ufi_command(priv, cbw->CBWCDB,
cbw->bCDBLength);
case PHASE_DATA:
debug("data out\n");
break;
default:
break;
}
case SANDBOX_FLASH_EP_IN:
switch (priv->phase) {
case PHASE_DATA:
debug("data in, len=%x, alloc_len=%x, priv->read_len=%x\n",
len, priv->alloc_len, priv->read_len);
if (priv->read_len) {
ulong bytes_read;
bytes_read = os_read(priv->fd, buff, len);
if (bytes_read != len)
return -EIO;
priv->read_len -= len / SANDBOX_FLASH_BLOCK_LEN;
if (!priv->read_len)
priv->phase = PHASE_STATUS;
} else {
if (priv->alloc_len && len > priv->alloc_len)
len = priv->alloc_len;
memcpy(buff, priv->buff, len);
priv->phase = PHASE_STATUS;
}
return len;
case PHASE_STATUS:
debug("status in, len=%x\n", len);
if (len > sizeof(priv->status))
len = sizeof(priv->status);
memcpy(buff, &priv->status, len);
priv->phase = PHASE_START;
return len;
default:
break;
}
}
err:
priv->error = true;
debug("%s: Detected transfer error\n", __func__);
return 0;
}
static int sandbox_flash_ofdata_to_platdata(struct udevice *dev)
{
struct sandbox_flash_plat *plat = dev_get_platdata(dev);
const void *blob = gd->fdt_blob;
plat->pathname = fdt_getprop(blob, dev->of_offset, "sandbox,filepath",
NULL);
return 0;
}
static int sandbox_flash_bind(struct udevice *dev)
{
return usb_emul_setup_device(dev, PACKET_SIZE_64, flash_strings,
flash_desc_list);
}
static int sandbox_flash_probe(struct udevice *dev)
{
struct sandbox_flash_plat *plat = dev_get_platdata(dev);
struct sandbox_flash_priv *priv = dev_get_priv(dev);
priv->fd = os_open(plat->pathname, OS_O_RDONLY);
if (priv->fd != -1)
return os_get_filesize(plat->pathname, &priv->file_size);
return 0;
}
static const struct dm_usb_ops sandbox_usb_flash_ops = {
.control = sandbox_flash_control,
.bulk = sandbox_flash_bulk,
};
static const struct udevice_id sandbox_usb_flash_ids[] = {
{ .compatible = "sandbox,usb-flash" },
{ }
};
U_BOOT_DRIVER(usb_sandbox_flash) = {
.name = "usb_sandbox_flash",
.id = UCLASS_USB_EMUL,
.of_match = sandbox_usb_flash_ids,
.bind = sandbox_flash_bind,
.probe = sandbox_flash_probe,
.ofdata_to_platdata = sandbox_flash_ofdata_to_platdata,
.ops = &sandbox_usb_flash_ops,
.priv_auto_alloc_size = sizeof(struct sandbox_flash_priv),
.platdata_auto_alloc_size = sizeof(struct sandbox_flash_plat),
};
......@@ -44,6 +44,7 @@ enum uclass_id {
UCLASS_USB, /* USB bus */
UCLASS_USB_HUB, /* USB hub */
UCLASS_USB_DEV_GENERIC, /* USB generic device */
UCLASS_MASS_STORAGE, /* Mass storage device */
UCLASS_COUNT,
UCLASS_INVALID = -1,
......
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