cxl: Support to flash a new image on the adapter from a guest

The new flash.c file contains the logic to flash a new image on the
adapter, through a hcall. It is an iterative process, with chunks of
data of 1M at a time. There are also 2 phases: write and verify. The
flash operation itself is driven from a user-land tool.
Once flashing is successful, an rtas call is made to update the device
tree with the new properties values for the adapter and the AFU(s)

Add a new char device for the adapter, so that the flash tool can
access the card, even if there is no valid AFU on it.

Co-authored-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com>
Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com>
Reviewed-by: Manoj Kumar <manoj@linux.vnet.ibm.com>
Acked-by: Ian Munsie <imunsie@au1.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Christophe Lombard 2016-03-04 12:26:38 +01:00 коммит произвёл Michael Ellerman
Родитель 4752876c71
Коммит 594ff7d067
8 изменённых файлов: 653 добавлений и 5 удалений

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@ -116,6 +116,8 @@ Work Element Descriptor (WED)
User API
========
1. AFU character devices
For AFUs operating in AFU directed mode, two character device
files will be created. /dev/cxl/afu0.0m will correspond to a
master context and /dev/cxl/afu0.0s will correspond to a slave
@ -362,6 +364,59 @@ read
reserved fields:
For future extensions and padding
2. Card character device (powerVM guest only)
In a powerVM guest, an extra character device is created for the
card. The device is only used to write (flash) a new image on the
FPGA accelerator. Once the image is written and verified, the
device tree is updated and the card is reset to reload the updated
image.
open
----
Opens the device and allocates a file descriptor to be used with
the rest of the API. The device can only be opened once.
ioctl
-----
CXL_IOCTL_DOWNLOAD_IMAGE:
CXL_IOCTL_VALIDATE_IMAGE:
Starts and controls flashing a new FPGA image. Partial
reconfiguration is not supported (yet), so the image must contain
a copy of the PSL and AFU(s). Since an image can be quite large,
the caller may have to iterate, splitting the image in smaller
chunks.
Takes a pointer to a struct cxl_adapter_image:
struct cxl_adapter_image {
__u64 flags;
__u64 data;
__u64 len_data;
__u64 len_image;
__u64 reserved1;
__u64 reserved2;
__u64 reserved3;
__u64 reserved4;
};
flags:
These flags indicate which optional fields are present in
this struct. Currently all fields are mandatory.
data:
Pointer to a buffer with part of the image to write to the
card.
len_data:
Size of the buffer pointed to by data.
len_image:
Full size of the image.
Sysfs Class
===========

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@ -4,7 +4,7 @@ ccflags-$(CONFIG_PPC_WERROR) += -Werror
cxl-y += main.o file.o irq.o fault.o native.o
cxl-y += context.o sysfs.o debugfs.o pci.o trace.o
cxl-y += vphb.o api.o
cxl-$(CONFIG_PPC_PSERIES) += guest.o of.o hcalls.o
cxl-$(CONFIG_PPC_PSERIES) += flash.o guest.o of.o hcalls.o
obj-$(CONFIG_CXL) += cxl.o
obj-$(CONFIG_CXL_BASE) += base.o

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@ -84,3 +84,10 @@ void unregister_cxl_calls(struct cxl_calls *calls)
synchronize_rcu();
}
EXPORT_SYMBOL_GPL(unregister_cxl_calls);
int cxl_update_properties(struct device_node *dn,
struct property *new_prop)
{
return of_update_property(dn, new_prop);
}
EXPORT_SYMBOL_GPL(cxl_update_properties);

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@ -324,6 +324,10 @@ static const cxl_p2n_reg_t CXL_PSL_WED_An = {0x0A0};
#define CXL_MODE_TIME_SLICED 0x4
#define CXL_SUPPORTED_MODES (CXL_MODE_DEDICATED | CXL_MODE_DIRECTED)
#define CXL_DEV_MINORS 13 /* 1 control + 4 AFUs * 3 (dedicated/master/shared) */
#define CXL_CARD_MINOR(adapter) (adapter->adapter_num * CXL_DEV_MINORS)
#define CXL_DEVT_ADAPTER(dev) (MINOR(dev) / CXL_DEV_MINORS)
enum cxl_context_status {
CLOSED,
OPENED,
@ -692,12 +696,14 @@ struct cxl_calls {
};
int register_cxl_calls(struct cxl_calls *calls);
void unregister_cxl_calls(struct cxl_calls *calls);
int cxl_update_properties(struct device_node *dn, struct property *new_prop);
void cxl_remove_adapter_nr(struct cxl *adapter);
int cxl_alloc_spa(struct cxl_afu *afu);
void cxl_release_spa(struct cxl_afu *afu);
dev_t cxl_get_dev(void);
int cxl_file_init(void);
void cxl_file_exit(void);
int cxl_register_adapter(struct cxl *adapter);

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@ -26,9 +26,7 @@
#include "trace.h"
#define CXL_NUM_MINORS 256 /* Total to reserve */
#define CXL_DEV_MINORS 13 /* 1 control + 4 AFUs * 3 (dedicated/master/shared) */
#define CXL_CARD_MINOR(adapter) (adapter->adapter_num * CXL_DEV_MINORS)
#define CXL_AFU_MINOR_D(afu) (CXL_CARD_MINOR(afu->adapter) + 1 + (3 * afu->slice))
#define CXL_AFU_MINOR_M(afu) (CXL_AFU_MINOR_D(afu) + 1)
#define CXL_AFU_MINOR_S(afu) (CXL_AFU_MINOR_D(afu) + 2)
@ -36,7 +34,6 @@
#define CXL_AFU_MKDEV_M(afu) MKDEV(MAJOR(cxl_dev), CXL_AFU_MINOR_M(afu))
#define CXL_AFU_MKDEV_S(afu) MKDEV(MAJOR(cxl_dev), CXL_AFU_MINOR_S(afu))
#define CXL_DEVT_ADAPTER(dev) (MINOR(dev) / CXL_DEV_MINORS)
#define CXL_DEVT_AFU(dev) ((MINOR(dev) % CXL_DEV_MINORS - 1) / 3)
#define CXL_DEVT_IS_CARD(dev) (MINOR(dev) % CXL_DEV_MINORS == 0)
@ -446,7 +443,8 @@ static const struct file_operations afu_master_fops = {
static char *cxl_devnode(struct device *dev, umode_t *mode)
{
if (CXL_DEVT_IS_CARD(dev->devt)) {
if (cpu_has_feature(CPU_FTR_HVMODE) &&
CXL_DEVT_IS_CARD(dev->devt)) {
/*
* These minor numbers will eventually be used to program the
* PSL and AFUs once we have dynamic reprogramming support
@ -547,6 +545,11 @@ int cxl_register_adapter(struct cxl *adapter)
return device_register(&adapter->dev);
}
dev_t cxl_get_dev(void)
{
return cxl_dev;
}
int __init cxl_file_init(void)
{
int rc;

538
drivers/misc/cxl/flash.c Normal file
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@ -0,0 +1,538 @@
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/semaphore.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <asm/rtas.h>
#include "cxl.h"
#include "hcalls.h"
#define DOWNLOAD_IMAGE 1
#define VALIDATE_IMAGE 2
struct ai_header {
u16 version;
u8 reserved0[6];
u16 vendor;
u16 device;
u16 subsystem_vendor;
u16 subsystem;
u64 image_offset;
u64 image_length;
u8 reserved1[96];
};
static struct semaphore sem;
unsigned long *buffer[CXL_AI_MAX_ENTRIES];
struct sg_list *le;
static u64 continue_token;
static unsigned int transfer;
struct update_props_workarea {
__be32 phandle;
__be32 state;
__be64 reserved;
__be32 nprops;
} __packed;
struct update_nodes_workarea {
__be32 state;
__be64 unit_address;
__be32 reserved;
} __packed;
#define DEVICE_SCOPE 3
#define NODE_ACTION_MASK 0xff000000
#define NODE_COUNT_MASK 0x00ffffff
#define OPCODE_DELETE 0x01000000
#define OPCODE_UPDATE 0x02000000
#define OPCODE_ADD 0x03000000
static int rcall(int token, char *buf, s32 scope)
{
int rc;
spin_lock(&rtas_data_buf_lock);
memcpy(rtas_data_buf, buf, RTAS_DATA_BUF_SIZE);
rc = rtas_call(token, 2, 1, NULL, rtas_data_buf, scope);
memcpy(buf, rtas_data_buf, RTAS_DATA_BUF_SIZE);
spin_unlock(&rtas_data_buf_lock);
return rc;
}
static int update_property(struct device_node *dn, const char *name,
u32 vd, char *value)
{
struct property *new_prop;
u32 *val;
int rc;
new_prop = kzalloc(sizeof(*new_prop), GFP_KERNEL);
if (!new_prop)
return -ENOMEM;
new_prop->name = kstrdup(name, GFP_KERNEL);
if (!new_prop->name) {
kfree(new_prop);
return -ENOMEM;
}
new_prop->length = vd;
new_prop->value = kzalloc(new_prop->length, GFP_KERNEL);
if (!new_prop->value) {
kfree(new_prop->name);
kfree(new_prop);
return -ENOMEM;
}
memcpy(new_prop->value, value, vd);
val = (u32 *)new_prop->value;
rc = cxl_update_properties(dn, new_prop);
pr_devel("%s: update property (%s, length: %i, value: %#x)\n",
dn->name, name, vd, be32_to_cpu(*val));
if (rc) {
kfree(new_prop->name);
kfree(new_prop->value);
kfree(new_prop);
}
return rc;
}
static int update_node(__be32 phandle, s32 scope)
{
struct update_props_workarea *upwa;
struct device_node *dn;
int i, rc, ret;
char *prop_data;
char *buf;
int token;
u32 nprops;
u32 vd;
token = rtas_token("ibm,update-properties");
if (token == RTAS_UNKNOWN_SERVICE)
return -EINVAL;
buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
if (!buf)
return -ENOMEM;
dn = of_find_node_by_phandle(be32_to_cpu(phandle));
if (!dn) {
kfree(buf);
return -ENOENT;
}
upwa = (struct update_props_workarea *)&buf[0];
upwa->phandle = phandle;
do {
rc = rcall(token, buf, scope);
if (rc < 0)
break;
prop_data = buf + sizeof(*upwa);
nprops = be32_to_cpu(upwa->nprops);
if (*prop_data == 0) {
prop_data++;
vd = be32_to_cpu(*(__be32 *)prop_data);
prop_data += vd + sizeof(vd);
nprops--;
}
for (i = 0; i < nprops; i++) {
char *prop_name;
prop_name = prop_data;
prop_data += strlen(prop_name) + 1;
vd = be32_to_cpu(*(__be32 *)prop_data);
prop_data += sizeof(vd);
if ((vd != 0x00000000) && (vd != 0x80000000)) {
ret = update_property(dn, prop_name, vd,
prop_data);
if (ret)
pr_err("cxl: Could not update property %s - %i\n",
prop_name, ret);
prop_data += vd;
}
}
} while (rc == 1);
of_node_put(dn);
kfree(buf);
return rc;
}
static int update_devicetree(struct cxl *adapter, s32 scope)
{
struct update_nodes_workarea *unwa;
u32 action, node_count;
int token, rc, i;
__be32 *data, drc_index, phandle;
char *buf;
token = rtas_token("ibm,update-nodes");
if (token == RTAS_UNKNOWN_SERVICE)
return -EINVAL;
buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
if (!buf)
return -ENOMEM;
unwa = (struct update_nodes_workarea *)&buf[0];
unwa->unit_address = cpu_to_be64(adapter->guest->handle);
do {
rc = rcall(token, buf, scope);
if (rc && rc != 1)
break;
data = (__be32 *)buf + 4;
while (be32_to_cpu(*data) & NODE_ACTION_MASK) {
action = be32_to_cpu(*data) & NODE_ACTION_MASK;
node_count = be32_to_cpu(*data) & NODE_COUNT_MASK;
pr_devel("device reconfiguration - action: %#x, nodes: %#x\n",
action, node_count);
data++;
for (i = 0; i < node_count; i++) {
phandle = *data++;
switch (action) {
case OPCODE_DELETE:
/* nothing to do */
break;
case OPCODE_UPDATE:
update_node(phandle, scope);
break;
case OPCODE_ADD:
/* nothing to do, just move pointer */
drc_index = *data++;
break;
}
}
}
} while (rc == 1);
kfree(buf);
return 0;
}
static int handle_image(struct cxl *adapter, int operation,
long (*fct)(u64, u64, u64, u64 *),
struct cxl_adapter_image *ai)
{
size_t mod, s_copy, len_chunk = 0;
struct ai_header *header = NULL;
unsigned int entries = 0, i;
void *dest, *from;
int rc = 0, need_header;
/* base adapter image header */
need_header = (ai->flags & CXL_AI_NEED_HEADER);
if (need_header) {
header = kzalloc(sizeof(struct ai_header), GFP_KERNEL);
if (!header)
return -ENOMEM;
header->version = cpu_to_be16(1);
header->vendor = cpu_to_be16(adapter->guest->vendor);
header->device = cpu_to_be16(adapter->guest->device);
header->subsystem_vendor = cpu_to_be16(adapter->guest->subsystem_vendor);
header->subsystem = cpu_to_be16(adapter->guest->subsystem);
header->image_offset = cpu_to_be64(CXL_AI_HEADER_SIZE);
header->image_length = cpu_to_be64(ai->len_image);
}
/* number of entries in the list */
len_chunk = ai->len_data;
if (need_header)
len_chunk += CXL_AI_HEADER_SIZE;
entries = len_chunk / CXL_AI_BUFFER_SIZE;
mod = len_chunk % CXL_AI_BUFFER_SIZE;
if (mod)
entries++;
if (entries > CXL_AI_MAX_ENTRIES) {
rc = -EINVAL;
goto err;
}
/* < -- MAX_CHUNK_SIZE = 4096 * 256 = 1048576 bytes -->
* chunk 0 ----------------------------------------------------
* | header | data |
* ----------------------------------------------------
* chunk 1 ----------------------------------------------------
* | data |
* ----------------------------------------------------
* ....
* chunk n ----------------------------------------------------
* | data |
* ----------------------------------------------------
*/
from = (void *) ai->data;
for (i = 0; i < entries; i++) {
dest = buffer[i];
s_copy = CXL_AI_BUFFER_SIZE;
if ((need_header) && (i == 0)) {
/* add adapter image header */
memcpy(buffer[i], header, sizeof(struct ai_header));
s_copy = CXL_AI_BUFFER_SIZE - CXL_AI_HEADER_SIZE;
dest += CXL_AI_HEADER_SIZE; /* image offset */
}
if ((i == (entries - 1)) && mod)
s_copy = mod;
/* copy data */
if (copy_from_user(dest, from, s_copy))
goto err;
/* fill in the list */
le[i].phys_addr = cpu_to_be64(virt_to_phys(buffer[i]));
le[i].len = cpu_to_be64(CXL_AI_BUFFER_SIZE);
if ((i == (entries - 1)) && mod)
le[i].len = cpu_to_be64(mod);
from += s_copy;
}
pr_devel("%s (op: %i, need header: %i, entries: %i, token: %#llx)\n",
__func__, operation, need_header, entries, continue_token);
/*
* download/validate the adapter image to the coherent
* platform facility
*/
rc = fct(adapter->guest->handle, virt_to_phys(le), entries,
&continue_token);
if (rc == 0) /* success of download/validation operation */
continue_token = 0;
err:
kfree(header);
return rc;
}
static int transfer_image(struct cxl *adapter, int operation,
struct cxl_adapter_image *ai)
{
int rc = 0;
int afu;
switch (operation) {
case DOWNLOAD_IMAGE:
rc = handle_image(adapter, operation,
&cxl_h_download_adapter_image, ai);
if (rc < 0) {
pr_devel("resetting adapter\n");
cxl_h_reset_adapter(adapter->guest->handle);
}
return rc;
case VALIDATE_IMAGE:
rc = handle_image(adapter, operation,
&cxl_h_validate_adapter_image, ai);
if (rc < 0) {
pr_devel("resetting adapter\n");
cxl_h_reset_adapter(adapter->guest->handle);
return rc;
}
if (rc == 0) {
pr_devel("remove curent afu\n");
for (afu = 0; afu < adapter->slices; afu++)
cxl_guest_remove_afu(adapter->afu[afu]);
pr_devel("resetting adapter\n");
cxl_h_reset_adapter(adapter->guest->handle);
/* The entire image has now been
* downloaded and the validation has
* been successfully performed.
* After that, the partition should call
* ibm,update-nodes and
* ibm,update-properties to receive the
* current configuration
*/
rc = update_devicetree(adapter, DEVICE_SCOPE);
transfer = 1;
}
return rc;
}
return -EINVAL;
}
static long ioctl_transfer_image(struct cxl *adapter, int operation,
struct cxl_adapter_image __user *uai)
{
struct cxl_adapter_image ai;
pr_devel("%s\n", __func__);
if (copy_from_user(&ai, uai, sizeof(struct cxl_adapter_image)))
return -EFAULT;
/*
* Make sure reserved fields and bits are set to 0
*/
if (ai.reserved1 || ai.reserved2 || ai.reserved3 || ai.reserved4 ||
(ai.flags & ~CXL_AI_ALL))
return -EINVAL;
return transfer_image(adapter, operation, &ai);
}
static int device_open(struct inode *inode, struct file *file)
{
int adapter_num = CXL_DEVT_ADAPTER(inode->i_rdev);
struct cxl *adapter;
int rc = 0, i;
pr_devel("in %s\n", __func__);
BUG_ON(sizeof(struct ai_header) != CXL_AI_HEADER_SIZE);
/* Allows one process to open the device by using a semaphore */
if (down_interruptible(&sem) != 0)
return -EPERM;
if (!(adapter = get_cxl_adapter(adapter_num)))
return -ENODEV;
file->private_data = adapter;
continue_token = 0;
transfer = 0;
for (i = 0; i < CXL_AI_MAX_ENTRIES; i++)
buffer[i] = NULL;
/* aligned buffer containing list entries which describes up to
* 1 megabyte of data (256 entries of 4096 bytes each)
* Logical real address of buffer 0 - Buffer 0 length in bytes
* Logical real address of buffer 1 - Buffer 1 length in bytes
* Logical real address of buffer 2 - Buffer 2 length in bytes
* ....
* ....
* Logical real address of buffer N - Buffer N length in bytes
*/
le = (struct sg_list *)get_zeroed_page(GFP_KERNEL);
if (!le) {
rc = -ENOMEM;
goto err;
}
for (i = 0; i < CXL_AI_MAX_ENTRIES; i++) {
buffer[i] = (unsigned long *)get_zeroed_page(GFP_KERNEL);
if (!buffer[i]) {
rc = -ENOMEM;
goto err1;
}
}
return 0;
err1:
for (i = 0; i < CXL_AI_MAX_ENTRIES; i++) {
if (buffer[i])
free_page((unsigned long) buffer[i]);
}
if (le)
free_page((unsigned long) le);
err:
put_device(&adapter->dev);
return rc;
}
static long device_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
struct cxl *adapter = file->private_data;
pr_devel("in %s\n", __func__);
if (cmd == CXL_IOCTL_DOWNLOAD_IMAGE)
return ioctl_transfer_image(adapter,
DOWNLOAD_IMAGE,
(struct cxl_adapter_image __user *)arg);
else if (cmd == CXL_IOCTL_VALIDATE_IMAGE)
return ioctl_transfer_image(adapter,
VALIDATE_IMAGE,
(struct cxl_adapter_image __user *)arg);
else
return -EINVAL;
}
static long device_compat_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
return device_ioctl(file, cmd, arg);
}
static int device_close(struct inode *inode, struct file *file)
{
struct cxl *adapter = file->private_data;
int i;
pr_devel("in %s\n", __func__);
for (i = 0; i < CXL_AI_MAX_ENTRIES; i++) {
if (buffer[i])
free_page((unsigned long) buffer[i]);
}
if (le)
free_page((unsigned long) le);
up(&sem);
put_device(&adapter->dev);
continue_token = 0;
/* reload the module */
if (transfer)
cxl_guest_reload_module(adapter);
else {
pr_devel("resetting adapter\n");
cxl_h_reset_adapter(adapter->guest->handle);
}
transfer = 0;
return 0;
}
static const struct file_operations fops = {
.owner = THIS_MODULE,
.open = device_open,
.unlocked_ioctl = device_ioctl,
.compat_ioctl = device_compat_ioctl,
.release = device_close,
};
void cxl_guest_remove_chardev(struct cxl *adapter)
{
cdev_del(&adapter->guest->cdev);
}
int cxl_guest_add_chardev(struct cxl *adapter)
{
dev_t devt;
int rc;
devt = MKDEV(MAJOR(cxl_get_dev()), CXL_CARD_MINOR(adapter));
cdev_init(&adapter->guest->cdev, &fops);
if ((rc = cdev_add(&adapter->guest->cdev, devt, 1))) {
dev_err(&adapter->dev,
"Unable to add chardev on adapter (card%i): %i\n",
adapter->adapter_num, rc);
goto err;
}
adapter->dev.devt = devt;
sema_init(&sem, 1);
err:
return rc;
}

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@ -889,6 +889,7 @@ void cxl_guest_remove_adapter(struct cxl *adapter)
cxl_sysfs_adapter_remove(adapter);
cxl_guest_remove_chardev(adapter);
device_unregister(&adapter->dev);
}
@ -926,6 +927,9 @@ struct cxl *cxl_guest_init_adapter(struct device_node *np, struct platform_devic
if ((rc = properties_look_ok(adapter)))
goto err1;
if ((rc = cxl_guest_add_chardev(adapter)))
goto err1;
/*
* After we call this function we must not free the adapter directly,
* even if it returns an error!
@ -941,12 +945,23 @@ struct cxl *cxl_guest_init_adapter(struct device_node *np, struct platform_devic
err_put1:
device_unregister(&adapter->dev);
free = false;
cxl_guest_remove_chardev(adapter);
err1:
if (free)
free_adapter(adapter);
return ERR_PTR(rc);
}
void cxl_guest_reload_module(struct cxl *adapter)
{
struct platform_device *pdev;
pdev = adapter->guest->pdev;
cxl_guest_remove_adapter(adapter);
cxl_of_probe(pdev);
}
const struct cxl_backend_ops cxl_guest_ops = {
.module = THIS_MODULE,
.adapter_reset = guest_reset,

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@ -55,11 +55,35 @@ struct cxl_afu_id {
__u64 reserved6;
};
/* base adapter image header is included in the image */
#define CXL_AI_NEED_HEADER 0x0000000000000001ULL
#define CXL_AI_ALL CXL_AI_NEED_HEADER
#define CXL_AI_HEADER_SIZE 128
#define CXL_AI_BUFFER_SIZE 4096
#define CXL_AI_MAX_ENTRIES 256
#define CXL_AI_MAX_CHUNK_SIZE (CXL_AI_BUFFER_SIZE * CXL_AI_MAX_ENTRIES)
struct cxl_adapter_image {
__u64 flags;
__u64 data;
__u64 len_data;
__u64 len_image;
__u64 reserved1;
__u64 reserved2;
__u64 reserved3;
__u64 reserved4;
};
/* ioctl numbers */
#define CXL_MAGIC 0xCA
/* AFU devices */
#define CXL_IOCTL_START_WORK _IOW(CXL_MAGIC, 0x00, struct cxl_ioctl_start_work)
#define CXL_IOCTL_GET_PROCESS_ELEMENT _IOR(CXL_MAGIC, 0x01, __u32)
#define CXL_IOCTL_GET_AFU_ID _IOR(CXL_MAGIC, 0x02, struct cxl_afu_id)
/* adapter devices */
#define CXL_IOCTL_DOWNLOAD_IMAGE _IOW(CXL_MAGIC, 0x0A, struct cxl_adapter_image)
#define CXL_IOCTL_VALIDATE_IMAGE _IOW(CXL_MAGIC, 0x0B, struct cxl_adapter_image)
#define CXL_READ_MIN_SIZE 0x1000 /* 4K */