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habanalabs: debugfs support for larger I2C transactions

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I2C debugfs support is limited to 1 byte. We extend functionality
to more than 1 byte by using one of the pad fields as a length.
No backward compatibility issues as new F/W versions will treat 0
length as a 1 byte length transaction.

Signed-off-by: Ofir Bitton <obitton@habana.ai>
Reviewed-by: Oded Gabbay <ogabbay@kernel.org>
Signed-off-by: Oded Gabbay <ogabbay@kernel.org>
This commit is contained in:
Ofir Bitton 2021-10-12 20:52:46 +03:00 committed by Oded Gabbay
parent e617f5f4c1
commit 3eb7754ff4
4 changed files with 50 additions and 18 deletions
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7
Documentation/ABI/testing/debugfs-driver-habanalabs
View File

@ -155,6 +155,13 @@ Description: Triggers an I2C transaction that is generated by the device's
CPU. Writing to this file generates a write transaction while
reading from the file generates a read transaction
What: /sys/kernel/debug/habanalabs/hl<n>/i2c_len
Date: Dec 2021
KernelVersion: 5.17
Contact: obitton@habana.ai
Description: Sets I2C length in bytes for I2C transaction that is generated by
the device's CPU
What: /sys/kernel/debug/habanalabs/hl<n>/i2c_reg
Date: Jan 2019
KernelVersion: 5.1

50
drivers/misc/habanalabs/common/debugfs.c
View File

@ -15,19 +15,25 @@
#define MMU_ADDR_BUF_SIZE 40
#define MMU_ASID_BUF_SIZE 10
#define MMU_KBUF_SIZE (MMU_ADDR_BUF_SIZE + MMU_ASID_BUF_SIZE)
#define I2C_MAX_TRANSACTION_LEN 8
static struct dentry *hl_debug_root;
static int hl_debugfs_i2c_read(struct hl_device *hdev, u8 i2c_bus, u8 i2c_addr,
u8 i2c_reg, long *val)
u8 i2c_reg, u8 i2c_len, u64 *val)
{
struct cpucp_packet pkt;
u64 result;
int rc;
if (!hl_device_operational(hdev, NULL))
return -EBUSY;
if (i2c_len > I2C_MAX_TRANSACTION_LEN) {
dev_err(hdev->dev, "I2C transaction length %u, exceeds maximum of %u\n",
i2c_len, I2C_MAX_TRANSACTION_LEN);
return -EINVAL;
}
memset(&pkt, 0, sizeof(pkt));
pkt.ctl = cpu_to_le32(CPUCP_PACKET_I2C_RD <<
@ -35,12 +41,10 @@ static int hl_debugfs_i2c_read(struct hl_device *hdev, u8 i2c_bus, u8 i2c_addr,
pkt.i2c_bus = i2c_bus;
pkt.i2c_addr = i2c_addr;
pkt.i2c_reg = i2c_reg;
pkt.i2c_len = i2c_len;
rc = hdev->asic_funcs->send_cpu_message(hdev, (u32 *) &pkt, sizeof(pkt),
0, &result);
*val = (long) result;
0, val);
if (rc)
dev_err(hdev->dev, "Failed to read from I2C, error %d\n", rc);
@ -48,7 +52,7 @@ static int hl_debugfs_i2c_read(struct hl_device *hdev, u8 i2c_bus, u8 i2c_addr,
}
static int hl_debugfs_i2c_write(struct hl_device *hdev, u8 i2c_bus, u8 i2c_addr,
u8 i2c_reg, u32 val)
u8 i2c_reg, u8 i2c_len, u64 val)
{
struct cpucp_packet pkt;
int rc;
@ -56,6 +60,12 @@ static int hl_debugfs_i2c_write(struct hl_device *hdev, u8 i2c_bus, u8 i2c_addr,
if (!hl_device_operational(hdev, NULL))
return -EBUSY;
if (i2c_len > I2C_MAX_TRANSACTION_LEN) {
dev_err(hdev->dev, "I2C transaction length %u, exceeds maximum of %u\n",
i2c_len, I2C_MAX_TRANSACTION_LEN);
return -EINVAL;
}
memset(&pkt, 0, sizeof(pkt));
pkt.ctl = cpu_to_le32(CPUCP_PACKET_I2C_WR <<
@ -63,6 +73,7 @@ static int hl_debugfs_i2c_write(struct hl_device *hdev, u8 i2c_bus, u8 i2c_addr,
pkt.i2c_bus = i2c_bus;
pkt.i2c_addr = i2c_addr;
pkt.i2c_reg = i2c_reg;
pkt.i2c_len = i2c_len;
pkt.value = cpu_to_le64(val);
rc = hdev->asic_funcs->send_cpu_message(hdev, (u32 *) &pkt, sizeof(pkt),
@ -899,22 +910,22 @@ static ssize_t hl_i2c_data_read(struct file *f, char __user *buf,
struct hl_dbg_device_entry *entry = file_inode(f)->i_private;
struct hl_device *hdev = entry->hdev;
char tmp_buf[32];
long val;
u64 val;
ssize_t rc;
if (*ppos)
return 0;
rc = hl_debugfs_i2c_read(hdev, entry->i2c_bus, entry->i2c_addr,
entry->i2c_reg, &val);
entry->i2c_reg, entry->i2c_len, &val);
if (rc) {
dev_err(hdev->dev,
"Failed to read from I2C bus %d, addr %d, reg %d\n",
entry->i2c_bus, entry->i2c_addr, entry->i2c_reg);
"Failed to read from I2C bus %d, addr %d, reg %d, len %d\n",
entry->i2c_bus, entry->i2c_addr, entry->i2c_reg, entry->i2c_len);
return rc;
}
sprintf(tmp_buf, "0x%02lx\n", val);
sprintf(tmp_buf, "%#02llx\n", val);
rc = simple_read_from_buffer(buf, count, ppos, tmp_buf,
strlen(tmp_buf));
@ -926,19 +937,19 @@ static ssize_t hl_i2c_data_write(struct file *f, const char __user *buf,
{
struct hl_dbg_device_entry *entry = file_inode(f)->i_private;
struct hl_device *hdev = entry->hdev;
u32 value;
u64 value;
ssize_t rc;
rc = kstrtouint_from_user(buf, count, 16, &value);
rc = kstrtou64_from_user(buf, count, 16, &value);
if (rc)
return rc;
rc = hl_debugfs_i2c_write(hdev, entry->i2c_bus, entry->i2c_addr,
entry->i2c_reg, value);
entry->i2c_reg, entry->i2c_len, value);
if (rc) {
dev_err(hdev->dev,
"Failed to write 0x%02x to I2C bus %d, addr %d, reg %d\n",
value, entry->i2c_bus, entry->i2c_addr, entry->i2c_reg);
"Failed to write %#02llx to I2C bus %d, addr %d, reg %d, len %d\n",
value, entry->i2c_bus, entry->i2c_addr, entry->i2c_reg, entry->i2c_len);
return rc;
}
@ -1421,6 +1432,11 @@ void hl_debugfs_add_device(struct hl_device *hdev)
dev_entry->root,
&dev_entry->i2c_reg);
debugfs_create_u8("i2c_len",
0644,
dev_entry->root,
&dev_entry->i2c_len);
debugfs_create_file("i2c_data",
0644,
dev_entry->root,

2
drivers/misc/habanalabs/common/habanalabs.h
View File

@ -1889,6 +1889,7 @@ struct hl_debugfs_entry {
* @i2c_bus: generic u8 debugfs file for bus value to use in i2c_data_read.
* @i2c_addr: generic u8 debugfs file for address value to use in i2c_data_read.
* @i2c_reg: generic u8 debugfs file for register value to use in i2c_data_read.
* @i2c_len: generic u8 debugfs file for length value to use in i2c_data_read.
*/
struct hl_dbg_device_entry {
struct dentry *root;
@ -1917,6 +1918,7 @@ struct hl_dbg_device_entry {
u8 i2c_bus;
u8 i2c_addr;
u8 i2c_reg;
u8 i2c_len;
};
/**

9
drivers/misc/habanalabs/include/common/cpucp_if.h
View File

@ -493,7 +493,14 @@ struct cpucp_packet {
__u8 i2c_bus;
__u8 i2c_addr;
__u8 i2c_reg;
__u8 pad; /* unused */
/*
* In legacy implemetations, i2c_len was not present,
* was unused and just added as pad.
* So if i2c_len is 0, it is treated as legacy
* and r/w 1 Byte, else if i2c_len is specified,
* its treated as new multibyte r/w support.
*/
__u8 i2c_len;
};
struct {/* For PLL info fetch */