The I2C Responder (I2CR) is an I2C device that translates I2C commands
to CFAM or SCOM operations, effectively implementing an FSI master and
bus.
Signed-off-by: Eddie James <[email protected]>
---
drivers/fsi/Kconfig | 9 +
drivers/fsi/Makefile | 1 +
drivers/fsi/fsi-master-i2cr.c | 225 +++++++++++++++++++++++++
include/trace/events/fsi_master_i2cr.h | 96 +++++++++++
4 files changed, 331 insertions(+)
create mode 100644 drivers/fsi/fsi-master-i2cr.c
create mode 100644 include/trace/events/fsi_master_i2cr.h
diff --git a/drivers/fsi/Kconfig b/drivers/fsi/Kconfig
index e6668a869913..999be82720c5 100644
--- a/drivers/fsi/Kconfig
+++ b/drivers/fsi/Kconfig
@@ -62,6 +62,15 @@ config FSI_MASTER_ASPEED
Enable it for your BMC kernel in an OpenPower or IBM Power system.
+config FSI_MASTER_I2CR
+ tristate "IBM I2C Responder virtual FSI master"
+ depends on I2C
+ help
+ This option enables a virtual FSI master in order to access a CFAM
+ behind an IBM I2C Responder (I2CR) chip. The I2CR is an I2C device
+ that translates I2C commands to CFAM or SCOM operations, effectively
+ implementing an FSI master and bus.
+
config FSI_SCOM
tristate "SCOM FSI client device driver"
help
diff --git a/drivers/fsi/Makefile b/drivers/fsi/Makefile
index da218a1ad8e1..34dbaa1c452e 100644
--- a/drivers/fsi/Makefile
+++ b/drivers/fsi/Makefile
@@ -4,6 +4,7 @@ obj-$(CONFIG_FSI) += fsi-core.o
obj-$(CONFIG_FSI_MASTER_HUB) += fsi-master-hub.o
obj-$(CONFIG_FSI_MASTER_ASPEED) += fsi-master-aspeed.o
obj-$(CONFIG_FSI_MASTER_GPIO) += fsi-master-gpio.o
+obj-$(CONFIG_FSI_MASTER_I2CR) += fsi-master-i2cr.o
obj-$(CONFIG_FSI_MASTER_AST_CF) += fsi-master-ast-cf.o
obj-$(CONFIG_FSI_SCOM) += fsi-scom.o
obj-$(CONFIG_FSI_SBEFIFO) += fsi-sbefifo.o
diff --git a/drivers/fsi/fsi-master-i2cr.c b/drivers/fsi/fsi-master-i2cr.c
new file mode 100644
index 000000000000..d19ac96c0a83
--- /dev/null
+++ b/drivers/fsi/fsi-master-i2cr.c
@@ -0,0 +1,225 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) IBM Corporation 2023 */
+
+#include <linux/device.h>
+#include <linux/fsi.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/mutex.h>
+
+#include "fsi-master.h"
+
+#define CREATE_TRACE_POINTS
+#include <trace/events/fsi_master_i2cr.h>
+
+#define I2CR_ADDRESS_CFAM(a) ((a) >> 2)
+#define I2CR_STATUS 0x30001
+#define I2CR_STATUS_ERR BIT_ULL(61)
+#define I2CR_ERROR 0x30002
+
+struct fsi_master_i2cr {
+ struct fsi_master master;
+ struct mutex lock; /* protect HW access */
+ struct i2c_client *client;
+};
+
+static bool i2cr_check_parity(u32 v, bool parity)
+{
+ u32 i;
+
+ for (i = 0; i < 32; ++i) {
+ if (v & (1 << i))
+ parity = !parity;
+ }
+
+ return parity;
+}
+
+static __be32 i2cr_get_command(u32 address, bool parity)
+{
+ __be32 command;
+
+ address <<= 1;
+
+ if (i2cr_check_parity(address, parity))
+ address |= 1;
+
+ command = cpu_to_be32(address);
+ trace_i2cr_command((__force uint32_t)command);
+
+ return command;
+}
+
+static int i2cr_transfer(struct i2c_client *client, u32 address, __be64 *data)
+{
+ struct i2c_msg msgs[2];
+ __be32 command;
+ int ret;
+
+ command = i2cr_get_command(address, true);
+ msgs[0].addr = client->addr;
+ msgs[0].flags = 0;
+ msgs[0].len = sizeof(command);
+ msgs[0].buf = (__u8 *)&command;
+ msgs[1].addr = client->addr;
+ msgs[1].flags = I2C_M_RD;
+ msgs[1].len = sizeof(*data);
+ msgs[1].buf = (__u8 *)data;
+
+ ret = i2c_transfer(client->adapter, msgs, 2);
+ if (ret == 2)
+ return 0;
+
+ trace_i2cr_i2c_error(ret);
+
+ if (ret < 0)
+ return ret;
+
+ return -EIO;
+}
+
+static int i2cr_check_status(struct i2c_client *client)
+{
+ __be64 status_be = 0;
+ u64 status;
+ int ret;
+
+ ret = i2cr_transfer(client, I2CR_STATUS, &status_be);
+ if (ret)
+ return ret;
+
+ status = be64_to_cpu(status_be);
+ if (status & I2CR_STATUS_ERR) {
+ __be64 error_be = 0;
+ u64 error;
+
+ i2cr_transfer(client, I2CR_ERROR, &error_be);
+ error = be64_to_cpu(error_be);
+ trace_i2cr_status_error(status, error);
+ dev_err(&client->dev, "status:%016llx error:%016llx\n", status, error);
+ return -EREMOTEIO;
+ }
+
+ trace_i2cr_status(status);
+ return 0;
+}
+
+static int i2cr_read(struct fsi_master *master, int link, uint8_t id, uint32_t addr, void *val,
+ size_t size)
+{
+ struct fsi_master_i2cr *i2cr = container_of(master, struct fsi_master_i2cr, master);
+ __be64 data = 0;
+ int ret;
+
+ if (link || id || (addr & 0xffff0000) || !size || size > 4 || size == 3)
+ return -EINVAL;
+
+ mutex_lock(&i2cr->lock);
+
+ ret = i2cr_transfer(i2cr->client, I2CR_ADDRESS_CFAM(addr), &data);
+ if (ret)
+ goto unlock;
+
+ ret = i2cr_check_status(i2cr->client);
+ if (ret)
+ goto unlock;
+
+ trace_i2cr_read(addr, size, (__force uint32_t)data);
+ memcpy(val, &data, size);
+
+unlock:
+ mutex_unlock(&i2cr->lock);
+ return ret;
+}
+
+static int i2cr_write(struct fsi_master *master, int link, uint8_t id, uint32_t addr,
+ const void *val, size_t size)
+{
+ struct fsi_master_i2cr *i2cr = container_of(master, struct fsi_master_i2cr, master);
+ __be32 data[3];
+ int ret;
+
+ if (link || id || (addr & 0xffff0000) || !size || size > 4 || size == 3)
+ return -EINVAL;
+
+ data[1] = 0;
+ memcpy(&data[1], val, size);
+ data[0] = i2cr_get_command(I2CR_ADDRESS_CFAM(addr),
+ i2cr_check_parity((__force u32)data[1], true));
+ data[2] = 0;
+
+ mutex_lock(&i2cr->lock);
+
+ ret = i2c_master_send(i2cr->client, (const char *)data, sizeof(data));
+ if (ret == sizeof(data)) {
+ ret = i2cr_check_status(i2cr->client);
+ if (!ret)
+ trace_i2cr_write(addr, size, (__force uint32_t)data[1]);
+ } else {
+ trace_i2cr_i2c_error(ret);
+
+ if (ret >= 0)
+ ret = -EIO;
+ }
+
+ mutex_unlock(&i2cr->lock);
+ return ret;
+}
+
+static int i2cr_probe(struct i2c_client *client)
+{
+ struct fsi_master_i2cr *i2cr;
+ int ret;
+
+ i2cr = devm_kzalloc(&client->dev, sizeof(*i2cr), GFP_KERNEL);
+ if (!i2cr)
+ return -ENOMEM;
+
+ i2cr->master.dev.parent = &client->dev;
+ i2cr->master.dev.of_node = of_node_get(dev_of_node(&client->dev));
+
+ i2cr->master.n_links = 1;
+ i2cr->master.read = i2cr_read;
+ i2cr->master.write = i2cr_write;
+
+ mutex_init(&i2cr->lock);
+ i2cr->client = client;
+
+ ret = fsi_master_register(&i2cr->master);
+ if (ret)
+ return ret;
+
+ i2c_set_clientdata(client, i2cr);
+ return 0;
+}
+
+static int i2cr_remove(struct i2c_client *client)
+{
+ struct fsi_master_i2cr *i2cr = i2c_get_clientdata(client);
+
+ fsi_master_unregister(&i2cr->master);
+
+ return 0;
+}
+
+static const struct of_device_id i2cr_i2c_ids[] = {
+ { .compatible = "ibm,i2cr", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, i2cr_i2c_ids);
+
+static struct i2c_driver i2cr_driver = {
+ .probe_new = i2cr_probe,
+ .remove = i2cr_remove,
+ .driver = {
+ .name = "i2cr",
+ .of_match_table = i2cr_i2c_ids,
+ },
+};
+
+module_i2c_driver(i2cr_driver)
+
+MODULE_AUTHOR("Eddie James <[email protected]>");
+MODULE_DESCRIPTION("IBM I2C Responder virtual FSI master driver");
+MODULE_LICENSE("GPL");
diff --git a/include/trace/events/fsi_master_i2cr.h b/include/trace/events/fsi_master_i2cr.h
new file mode 100644
index 000000000000..7b53c6a35bc7
--- /dev/null
+++ b/include/trace/events/fsi_master_i2cr.h
@@ -0,0 +1,96 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM fsi_master_i2cr
+
+#if !defined(_TRACE_FSI_MASTER_I2CR_H) || defined(TRACE_HEADER_MULTI_READ)
+#define _TRACE_FSI_MASTER_I2CR_H
+
+#include <linux/tracepoint.h>
+
+TRACE_EVENT(i2cr_command,
+ TP_PROTO(uint32_t command),
+ TP_ARGS(command),
+ TP_STRUCT__entry(
+ __field(uint32_t, command)
+ ),
+ TP_fast_assign(
+ __entry->command = command;
+ ),
+ TP_printk("command:%08x", __entry->command)
+);
+
+TRACE_EVENT(i2cr_i2c_error,
+ TP_PROTO(int rc),
+ TP_ARGS(rc),
+ TP_STRUCT__entry(
+ __field(int, rc)
+ ),
+ TP_fast_assign(
+ __entry->rc = rc;
+ ),
+ TP_printk("rc:%d", __entry->rc)
+);
+
+TRACE_EVENT(i2cr_read,
+ TP_PROTO(uint32_t addr, size_t size, uint64_t result),
+ TP_ARGS(addr, size, result),
+ TP_STRUCT__entry(
+ __field(uint32_t, addr)
+ __field(size_t, size)
+ __field(uint64_t, result)
+ ),
+ TP_fast_assign(
+ __entry->addr = addr;
+ __entry->size = size;
+ __entry->result = result;
+ ),
+ TP_printk("addr:%08x size:%zu result:%016llx", __entry->addr, __entry->size,
+ __entry->result)
+);
+
+TRACE_EVENT(i2cr_status,
+ TP_PROTO(uint64_t status),
+ TP_ARGS(status),
+ TP_STRUCT__entry(
+ __field(uint32_t, status)
+ ),
+ TP_fast_assign(
+ __entry->status = status >> 32;
+ ),
+ TP_printk("status:%08x", __entry->status)
+);
+
+TRACE_EVENT(i2cr_status_error,
+ TP_PROTO(uint64_t status, uint64_t error),
+ TP_ARGS(status, error),
+ TP_STRUCT__entry(
+ __field(uint64_t, error)
+ __field(uint32_t, status)
+ ),
+ TP_fast_assign(
+ __entry->error = error;
+ __entry->status = status >> 32;
+ ),
+ TP_printk("status:%08x error:%016llx", __entry->status, __entry->error)
+);
+
+TRACE_EVENT(i2cr_write,
+ TP_PROTO(uint32_t addr, uint32_t val, size_t size),
+ TP_ARGS(addr, val, size),
+ TP_STRUCT__entry(
+ __field(uint32_t, addr)
+ __field(uint32_t, val)
+ __field(size_t, size)
+ ),
+ TP_fast_assign(
+ __entry->addr = addr;
+ __entry->val = val;
+ __entry->size = size;
+ ),
+ TP_printk("addr:%08x val:%08x size:%zu", __entry->addr, __entry->val, __entry->size)
+);
+
+#endif
+
+#include <trace/define_trace.h>
--
2.31.1
On Fri, 20 Jan 2023, at 04:17, Eddie James wrote:
> The I2C Responder (I2CR) is an I2C device that translates I2C commands
> to CFAM or SCOM operations, effectively implementing an FSI master and
> bus.
>
> Signed-off-by: Eddie James <[email protected]>
> ---
> drivers/fsi/Kconfig | 9 +
> drivers/fsi/Makefile | 1 +
> drivers/fsi/fsi-master-i2cr.c | 225 +++++++++++++++++++++++++
> include/trace/events/fsi_master_i2cr.h | 96 +++++++++++
> 4 files changed, 331 insertions(+)
> create mode 100644 drivers/fsi/fsi-master-i2cr.c
> create mode 100644 include/trace/events/fsi_master_i2cr.h
>
> diff --git a/drivers/fsi/Kconfig b/drivers/fsi/Kconfig
> index e6668a869913..999be82720c5 100644
> --- a/drivers/fsi/Kconfig
> +++ b/drivers/fsi/Kconfig
> @@ -62,6 +62,15 @@ config FSI_MASTER_ASPEED
>
> Enable it for your BMC kernel in an OpenPower or IBM Power system.
>
> +config FSI_MASTER_I2CR
> + tristate "IBM I2C Responder virtual FSI master"
> + depends on I2C
> + help
> + This option enables a virtual FSI master in order to access a CFAM
> + behind an IBM I2C Responder (I2CR) chip. The I2CR is an I2C device
> + that translates I2C commands to CFAM or SCOM operations, effectively
> + implementing an FSI master and bus.
> +
> config FSI_SCOM
> tristate "SCOM FSI client device driver"
> help
> diff --git a/drivers/fsi/Makefile b/drivers/fsi/Makefile
> index da218a1ad8e1..34dbaa1c452e 100644
> --- a/drivers/fsi/Makefile
> +++ b/drivers/fsi/Makefile
> @@ -4,6 +4,7 @@ obj-$(CONFIG_FSI) += fsi-core.o
> obj-$(CONFIG_FSI_MASTER_HUB) += fsi-master-hub.o
> obj-$(CONFIG_FSI_MASTER_ASPEED) += fsi-master-aspeed.o
> obj-$(CONFIG_FSI_MASTER_GPIO) += fsi-master-gpio.o
> +obj-$(CONFIG_FSI_MASTER_I2CR) += fsi-master-i2cr.o
> obj-$(CONFIG_FSI_MASTER_AST_CF) += fsi-master-ast-cf.o
> obj-$(CONFIG_FSI_SCOM) += fsi-scom.o
> obj-$(CONFIG_FSI_SBEFIFO) += fsi-sbefifo.o
> diff --git a/drivers/fsi/fsi-master-i2cr.c
> b/drivers/fsi/fsi-master-i2cr.c
> new file mode 100644
> index 000000000000..d19ac96c0a83
> --- /dev/null
> +++ b/drivers/fsi/fsi-master-i2cr.c
> @@ -0,0 +1,225 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Copyright (C) IBM Corporation 2023 */
> +
> +#include <linux/device.h>
> +#include <linux/fsi.h>
> +#include <linux/i2c.h>
> +#include <linux/module.h>
> +#include <linux/mod_devicetable.h>
> +#include <linux/mutex.h>
> +
> +#include "fsi-master.h"
> +
> +#define CREATE_TRACE_POINTS
> +#include <trace/events/fsi_master_i2cr.h>
> +
> +#define I2CR_ADDRESS_CFAM(a) ((a) >> 2)
> +#define I2CR_STATUS 0x30001
> +#define I2CR_STATUS_ERR BIT_ULL(61)
> +#define I2CR_ERROR 0x30002
> +
> +struct fsi_master_i2cr {
> + struct fsi_master master;
> + struct mutex lock; /* protect HW access */
> + struct i2c_client *client;
> +};
> +
> +static bool i2cr_check_parity(u32 v, bool parity)
> +{
> + u32 i;
> +
> + for (i = 0; i < 32; ++i) {
> + if (v & (1 << i))
> + parity = !parity;
> + }
> +
> + return parity;
> +}
> +
> +static __be32 i2cr_get_command(u32 address, bool parity)
> +{
> + __be32 command;
> +
> + address <<= 1;
> +
> + if (i2cr_check_parity(address, parity))
> + address |= 1;
> +
> + command = cpu_to_be32(address);
> + trace_i2cr_command((__force uint32_t)command);
> +
> + return command;
> +}
> +
> +static int i2cr_transfer(struct i2c_client *client, u32 address,
> __be64 *data)
Is there a reason to use __be64 *data here and not `void *data, size_t
len`? We never actually use it as the declared type internally, only
cast it to __u8 *.
> +{
> + struct i2c_msg msgs[2];
> + __be32 command;
> + int ret;
> +
> + command = i2cr_get_command(address, true);
> + msgs[0].addr = client->addr;
> + msgs[0].flags = 0;
> + msgs[0].len = sizeof(command);
> + msgs[0].buf = (__u8 *)&command;
> + msgs[1].addr = client->addr;
> + msgs[1].flags = I2C_M_RD;
> + msgs[1].len = sizeof(*data);
> + msgs[1].buf = (__u8 *)data;
> +
> + ret = i2c_transfer(client->adapter, msgs, 2);
> + if (ret == 2)
> + return 0;
> +
> + trace_i2cr_i2c_error(ret);
> +
> + if (ret < 0)
> + return ret;
> +
> + return -EIO;
> +}
> +
> +static int i2cr_check_status(struct i2c_client *client)
> +{
> + __be64 status_be = 0;
> + u64 status;
> + int ret;
> +
> + ret = i2cr_transfer(client, I2CR_STATUS, &status_be);
> + if (ret)
> + return ret;
> +
> + status = be64_to_cpu(status_be);
> + if (status & I2CR_STATUS_ERR) {
> + __be64 error_be = 0;
> + u64 error;
> +
> + i2cr_transfer(client, I2CR_ERROR, &error_be);
> + error = be64_to_cpu(error_be);
> + trace_i2cr_status_error(status, error);
> + dev_err(&client->dev, "status:%016llx error:%016llx\n", status,
> error);
> + return -EREMOTEIO;
> + }
> +
> + trace_i2cr_status(status);
> + return 0;
> +}
> +
> +static int i2cr_read(struct fsi_master *master, int link, uint8_t id,
> uint32_t addr, void *val,
> + size_t size)
> +{
> + struct fsi_master_i2cr *i2cr = container_of(master, struct
> fsi_master_i2cr, master);
> + __be64 data = 0;
> + int ret;
> +
> + if (link || id || (addr & 0xffff0000) || !size || size > 4 || size ==
> 3)
These size constraints are a bit funky. Instead of `!size || size > 4 ||
size == 3` we write `!(size == 1 || size == 2 || size == 4)`?
> + return -EINVAL;
> +
> + mutex_lock(&i2cr->lock);
> +
> + ret = i2cr_transfer(i2cr->client, I2CR_ADDRESS_CFAM(addr), &data);
> + if (ret)
> + goto unlock;
> +
> + ret = i2cr_check_status(i2cr->client);
> + if (ret)
> + goto unlock;
> +
> + trace_i2cr_read(addr, size, (__force uint32_t)data);
> + memcpy(val, &data, size);
> +
> +unlock:
> + mutex_unlock(&i2cr->lock);
> + return ret;
> +}
> +
> +static int i2cr_write(struct fsi_master *master, int link, uint8_t id,
> uint32_t addr,
> + const void *val, size_t size)
> +{
> + struct fsi_master_i2cr *i2cr = container_of(master, struct
> fsi_master_i2cr, master);
> + __be32 data[3];
> + int ret;
> +
> + if (link || id || (addr & 0xffff0000) || !size || size > 4 || size ==
> 3)
As above
> + return -EINVAL;
> +
> + data[1] = 0;
> + memcpy(&data[1], val, size);
> + data[0] = i2cr_get_command(I2CR_ADDRESS_CFAM(addr),
> + i2cr_check_parity((__force u32)data[1], true));
> + data[2] = 0;
> +
> + mutex_lock(&i2cr->lock);
> +
> + ret = i2c_master_send(i2cr->client, (const char *)data, sizeof(data));
> + if (ret == sizeof(data)) {
> + ret = i2cr_check_status(i2cr->client);
> + if (!ret)
> + trace_i2cr_write(addr, size, (__force uint32_t)data[1]);
I think we can reduce the amount of __force if we flip the endianness
of the data variable?
```
u32 data[3];
__be32 cmd_be;
data[1] = 0;
memcpy(&data[1], val, size);
cmd_be = i2cr_get_command(I2CR_ADDRESS_CFAM(addr),
i2cr_check_parity(data[1], true));
data[0] = (__force u32)cmd_be;
data[2] = 0;
....
trace_i2cr_write(addr, size, data[1]);
```
?
Or define i2cr_check_parity() and the tracepoint in terms of big-endian?
> + } else {
> + trace_i2cr_i2c_error(ret);
> +
> + if (ret >= 0)
> + ret = -EIO;
> + }
> +
> + mutex_unlock(&i2cr->lock);
> + return ret;
> +}
> +
> +static int i2cr_probe(struct i2c_client *client)
> +{
> + struct fsi_master_i2cr *i2cr;
> + int ret;
> +
> + i2cr = devm_kzalloc(&client->dev, sizeof(*i2cr), GFP_KERNEL);
> + if (!i2cr)
> + return -ENOMEM;
> +
> + i2cr->master.dev.parent = &client->dev;
> + i2cr->master.dev.of_node = of_node_get(dev_of_node(&client->dev));
> +
> + i2cr->master.n_links = 1;
> + i2cr->master.read = i2cr_read;
> + i2cr->master.write = i2cr_write;
> +
> + mutex_init(&i2cr->lock);
> + i2cr->client = client;
> +
> + ret = fsi_master_register(&i2cr->master);
> + if (ret)
> + return ret;
> +
> + i2c_set_clientdata(client, i2cr);
> + return 0;
> +}
> +
> +static int i2cr_remove(struct i2c_client *client)
> +{
> + struct fsi_master_i2cr *i2cr = i2c_get_clientdata(client);
> +
> + fsi_master_unregister(&i2cr->master);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id i2cr_i2c_ids[] = {
> + { .compatible = "ibm,i2cr", },
This may need an update after discussion on the binding patch.
Andrew
Hi Eddie,
I love your patch! Yet something to improve:
[auto build test ERROR on robh/for-next]
[also build test ERROR on linus/master v6.2-rc4 next-20230120]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Eddie-James/dt-bindings-fsi-Document-the-IBM-I2C-Responder-virtual-FSI-master/20230120-014831
base: https://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git for-next
patch link: https://lore.kernel.org/r/20230119174714.1486042-3-eajames%40linux.ibm.com
patch subject: [PATCH 2/2] fsi: Add IBM I2C Responder virtual FSI master
config: alpha-allyesconfig (https://download.01.org/0day-ci/archive/20230120/[email protected]/config)
compiler: alpha-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/1312ba80b81ef02457d213ee6bc6ee80739c3e01
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Eddie-James/dt-bindings-fsi-Document-the-IBM-I2C-Responder-virtual-FSI-master/20230120-014831
git checkout 1312ba80b81ef02457d213ee6bc6ee80739c3e01
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=alpha olddefconfig
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=alpha SHELL=/bin/bash
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <[email protected]>
All errors (new ones prefixed by >>):
>> drivers/fsi/fsi-master-i2cr.c:214:19: error: initialization of 'void (*)(struct i2c_client *)' from incompatible pointer type 'int (*)(struct i2c_client *)' [-Werror=incompatible-pointer-types]
214 | .remove = i2cr_remove,
| ^~~~~~~~~~~
drivers/fsi/fsi-master-i2cr.c:214:19: note: (near initialization for 'i2cr_driver.remove')
cc1: some warnings being treated as errors
vim +214 drivers/fsi/fsi-master-i2cr.c
211
212 static struct i2c_driver i2cr_driver = {
213 .probe_new = i2cr_probe,
> 214 .remove = i2cr_remove,
215 .driver = {
216 .name = "i2cr",
217 .of_match_table = i2cr_i2c_ids,
218 },
219 };
220
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests
Hi Eddie,
I love your patch! Yet something to improve:
[auto build test ERROR on robh/for-next]
[also build test ERROR on linus/master v6.2-rc4 next-20230120]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Eddie-James/dt-bindings-fsi-Document-the-IBM-I2C-Responder-virtual-FSI-master/20230120-014831
base: https://git.kernel.org/pub/scm/linux/kernel/git/robh/linux.git for-next
patch link: https://lore.kernel.org/r/20230119174714.1486042-3-eajames%40linux.ibm.com
patch subject: [PATCH 2/2] fsi: Add IBM I2C Responder virtual FSI master
config: arm-randconfig-c002-20230120 (https://download.01.org/0day-ci/archive/20230121/[email protected]/config)
compiler: clang version 16.0.0 (https://github.com/llvm/llvm-project 4196ca3278f78c6e19246e54ab0ecb364e37d66a)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install arm cross compiling tool for clang build
# apt-get install binutils-arm-linux-gnueabi
# https://github.com/intel-lab-lkp/linux/commit/1312ba80b81ef02457d213ee6bc6ee80739c3e01
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Eddie-James/dt-bindings-fsi-Document-the-IBM-I2C-Responder-virtual-FSI-master/20230120-014831
git checkout 1312ba80b81ef02457d213ee6bc6ee80739c3e01
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm olddefconfig
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm SHELL=/bin/bash drivers/fsi/
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <[email protected]>
All errors (new ones prefixed by >>):
>> drivers/fsi/fsi-master-i2cr.c:214:12: error: incompatible function pointer types initializing 'void (*)(struct i2c_client *)' with an expression of type 'int (struct i2c_client *)' [-Wincompatible-function-pointer-types]
.remove = i2cr_remove,
^~~~~~~~~~~
1 error generated.
vim +214 drivers/fsi/fsi-master-i2cr.c
211
212 static struct i2c_driver i2cr_driver = {
213 .probe_new = i2cr_probe,
> 214 .remove = i2cr_remove,
215 .driver = {
216 .name = "i2cr",
217 .of_match_table = i2cr_i2c_ids,
218 },
219 };
220
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests
On 1/19/23 19:09, Andrew Jeffery wrote:
>
> On Fri, 20 Jan 2023, at 04:17, Eddie James wrote:
>> The I2C Responder (I2CR) is an I2C device that translates I2C commands
>> to CFAM or SCOM operations, effectively implementing an FSI master and
>> bus.
>>
>> Signed-off-by: Eddie James <[email protected]>
>> ---
>> drivers/fsi/Kconfig | 9 +
>> drivers/fsi/Makefile | 1 +
>> drivers/fsi/fsi-master-i2cr.c | 225 +++++++++++++++++++++++++
>> include/trace/events/fsi_master_i2cr.h | 96 +++++++++++
>> 4 files changed, 331 insertions(+)
>> create mode 100644 drivers/fsi/fsi-master-i2cr.c
>> create mode 100644 include/trace/events/fsi_master_i2cr.h
>>
>> diff --git a/drivers/fsi/Kconfig b/drivers/fsi/Kconfig
>> index e6668a869913..999be82720c5 100644
>> --- a/drivers/fsi/Kconfig
>> +++ b/drivers/fsi/Kconfig
>> @@ -62,6 +62,15 @@ config FSI_MASTER_ASPEED
>>
>> Enable it for your BMC kernel in an OpenPower or IBM Power system.
>>
>> +config FSI_MASTER_I2CR
>> + tristate "IBM I2C Responder virtual FSI master"
>> + depends on I2C
>> + help
>> + This option enables a virtual FSI master in order to access a CFAM
>> + behind an IBM I2C Responder (I2CR) chip. The I2CR is an I2C device
>> + that translates I2C commands to CFAM or SCOM operations, effectively
>> + implementing an FSI master and bus.
>> +
>> config FSI_SCOM
>> tristate "SCOM FSI client device driver"
>> help
>> diff --git a/drivers/fsi/Makefile b/drivers/fsi/Makefile
>> index da218a1ad8e1..34dbaa1c452e 100644
>> --- a/drivers/fsi/Makefile
>> +++ b/drivers/fsi/Makefile
>> @@ -4,6 +4,7 @@ obj-$(CONFIG_FSI) += fsi-core.o
>> obj-$(CONFIG_FSI_MASTER_HUB) += fsi-master-hub.o
>> obj-$(CONFIG_FSI_MASTER_ASPEED) += fsi-master-aspeed.o
>> obj-$(CONFIG_FSI_MASTER_GPIO) += fsi-master-gpio.o
>> +obj-$(CONFIG_FSI_MASTER_I2CR) += fsi-master-i2cr.o
>> obj-$(CONFIG_FSI_MASTER_AST_CF) += fsi-master-ast-cf.o
>> obj-$(CONFIG_FSI_SCOM) += fsi-scom.o
>> obj-$(CONFIG_FSI_SBEFIFO) += fsi-sbefifo.o
>> diff --git a/drivers/fsi/fsi-master-i2cr.c
>> b/drivers/fsi/fsi-master-i2cr.c
>> new file mode 100644
>> index 000000000000..d19ac96c0a83
>> --- /dev/null
>> +++ b/drivers/fsi/fsi-master-i2cr.c
>> @@ -0,0 +1,225 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/* Copyright (C) IBM Corporation 2023 */
>> +
>> +#include <linux/device.h>
>> +#include <linux/fsi.h>
>> +#include <linux/i2c.h>
>> +#include <linux/module.h>
>> +#include <linux/mod_devicetable.h>
>> +#include <linux/mutex.h>
>> +
>> +#include "fsi-master.h"
>> +
>> +#define CREATE_TRACE_POINTS
>> +#include <trace/events/fsi_master_i2cr.h>
>> +
>> +#define I2CR_ADDRESS_CFAM(a) ((a) >> 2)
>> +#define I2CR_STATUS 0x30001
>> +#define I2CR_STATUS_ERR BIT_ULL(61)
>> +#define I2CR_ERROR 0x30002
>> +
>> +struct fsi_master_i2cr {
>> + struct fsi_master master;
>> + struct mutex lock; /* protect HW access */
>> + struct i2c_client *client;
>> +};
>> +
>> +static bool i2cr_check_parity(u32 v, bool parity)
>> +{
>> + u32 i;
>> +
>> + for (i = 0; i < 32; ++i) {
>> + if (v & (1 << i))
>> + parity = !parity;
>> + }
>> +
>> + return parity;
>> +}
>> +
>> +static __be32 i2cr_get_command(u32 address, bool parity)
>> +{
>> + __be32 command;
>> +
>> + address <<= 1;
>> +
>> + if (i2cr_check_parity(address, parity))
>> + address |= 1;
>> +
>> + command = cpu_to_be32(address);
>> + trace_i2cr_command((__force uint32_t)command);
>> +
>> + return command;
>> +}
>> +
>> +static int i2cr_transfer(struct i2c_client *client, u32 address,
>> __be64 *data)
> Is there a reason to use __be64 *data here and not `void *data, size_t
> len`? We never actually use it as the declared type internally, only
> cast it to __u8 *.
Well, its mostly to ensure the user buffer is at least 8 bytes. We have
to read 8 bytes of data, so passing in a length doesn't really make sense?
>
>> +{
>> + struct i2c_msg msgs[2];
>> + __be32 command;
>> + int ret;
>> +
>> + command = i2cr_get_command(address, true);
>> + msgs[0].addr = client->addr;
>> + msgs[0].flags = 0;
>> + msgs[0].len = sizeof(command);
>> + msgs[0].buf = (__u8 *)&command;
>> + msgs[1].addr = client->addr;
>> + msgs[1].flags = I2C_M_RD;
>> + msgs[1].len = sizeof(*data);
>> + msgs[1].buf = (__u8 *)data;
>> +
>> + ret = i2c_transfer(client->adapter, msgs, 2);
>> + if (ret == 2)
>> + return 0;
>> +
>> + trace_i2cr_i2c_error(ret);
>> +
>> + if (ret < 0)
>> + return ret;
>> +
>> + return -EIO;
>> +}
>> +
>> +static int i2cr_check_status(struct i2c_client *client)
>> +{
>> + __be64 status_be = 0;
>> + u64 status;
>> + int ret;
>> +
>> + ret = i2cr_transfer(client, I2CR_STATUS, &status_be);
>> + if (ret)
>> + return ret;
>> +
>> + status = be64_to_cpu(status_be);
>> + if (status & I2CR_STATUS_ERR) {
>> + __be64 error_be = 0;
>> + u64 error;
>> +
>> + i2cr_transfer(client, I2CR_ERROR, &error_be);
>> + error = be64_to_cpu(error_be);
>> + trace_i2cr_status_error(status, error);
>> + dev_err(&client->dev, "status:%016llx error:%016llx\n", status,
>> error);
>> + return -EREMOTEIO;
>> + }
>> +
>> + trace_i2cr_status(status);
>> + return 0;
>> +}
>> +
>> +static int i2cr_read(struct fsi_master *master, int link, uint8_t id,
>> uint32_t addr, void *val,
>> + size_t size)
>> +{
>> + struct fsi_master_i2cr *i2cr = container_of(master, struct
>> fsi_master_i2cr, master);
>> + __be64 data = 0;
>> + int ret;
>> +
>> + if (link || id || (addr & 0xffff0000) || !size || size > 4 || size ==
>> 3)
> These size constraints are a bit funky. Instead of `!size || size > 4 ||
> size == 3` we write `!(size == 1 || size == 2 || size == 4)`?
Good idea, thanks.
>
>> + return -EINVAL;
>> +
>> + mutex_lock(&i2cr->lock);
>> +
>> + ret = i2cr_transfer(i2cr->client, I2CR_ADDRESS_CFAM(addr), &data);
>> + if (ret)
>> + goto unlock;
>> +
>> + ret = i2cr_check_status(i2cr->client);
>> + if (ret)
>> + goto unlock;
>> +
>> + trace_i2cr_read(addr, size, (__force uint32_t)data);
>> + memcpy(val, &data, size);
>> +
>> +unlock:
>> + mutex_unlock(&i2cr->lock);
>> + return ret;
>> +}
>> +
>> +static int i2cr_write(struct fsi_master *master, int link, uint8_t id,
>> uint32_t addr,
>> + const void *val, size_t size)
>> +{
>> + struct fsi_master_i2cr *i2cr = container_of(master, struct
>> fsi_master_i2cr, master);
>> + __be32 data[3];
>> + int ret;
>> +
>> + if (link || id || (addr & 0xffff0000) || !size || size > 4 || size ==
>> 3)
> As above
>
>> + return -EINVAL;
>> +
>> + data[1] = 0;
>> + memcpy(&data[1], val, size);
>> + data[0] = i2cr_get_command(I2CR_ADDRESS_CFAM(addr),
>> + i2cr_check_parity((__force u32)data[1], true));
>> + data[2] = 0;
>> +
>> + mutex_lock(&i2cr->lock);
>> +
>> + ret = i2c_master_send(i2cr->client, (const char *)data, sizeof(data));
>> + if (ret == sizeof(data)) {
>> + ret = i2cr_check_status(i2cr->client);
>> + if (!ret)
>> + trace_i2cr_write(addr, size, (__force uint32_t)data[1]);
> I think we can reduce the amount of __force if we flip the endianness
> of the data variable?
>
> ```
> u32 data[3];
> __be32 cmd_be;
>
> data[1] = 0;
> memcpy(&data[1], val, size);
> cmd_be = i2cr_get_command(I2CR_ADDRESS_CFAM(addr),
> i2cr_check_parity(data[1], true));
> data[0] = (__force u32)cmd_be;
> data[2] = 0;
> ....
> trace_i2cr_write(addr, size, data[1]);
> ```
>
> ?
>
> Or define i2cr_check_parity() and the tracepoint in terms of big-endian?
I think I'll define a struct with the command as __be32 and the data as
u32. That should clean it up.
>
>> + } else {
>> + trace_i2cr_i2c_error(ret);
>> +
>> + if (ret >= 0)
>> + ret = -EIO;
>> + }
>> +
>> + mutex_unlock(&i2cr->lock);
>> + return ret;
>> +}
>> +
>> +static int i2cr_probe(struct i2c_client *client)
>> +{
>> + struct fsi_master_i2cr *i2cr;
>> + int ret;
>> +
>> + i2cr = devm_kzalloc(&client->dev, sizeof(*i2cr), GFP_KERNEL);
>> + if (!i2cr)
>> + return -ENOMEM;
>> +
>> + i2cr->master.dev.parent = &client->dev;
>> + i2cr->master.dev.of_node = of_node_get(dev_of_node(&client->dev));
>> +
>> + i2cr->master.n_links = 1;
>> + i2cr->master.read = i2cr_read;
>> + i2cr->master.write = i2cr_write;
>> +
>> + mutex_init(&i2cr->lock);
>> + i2cr->client = client;
>> +
>> + ret = fsi_master_register(&i2cr->master);
>> + if (ret)
>> + return ret;
>> +
>> + i2c_set_clientdata(client, i2cr);
>> + return 0;
>> +}
>> +
>> +static int i2cr_remove(struct i2c_client *client)
>> +{
>> + struct fsi_master_i2cr *i2cr = i2c_get_clientdata(client);
>> +
>> + fsi_master_unregister(&i2cr->master);
>> +
>> + return 0;
>> +}
>> +
>> +static const struct of_device_id i2cr_i2c_ids[] = {
>> + { .compatible = "ibm,i2cr", },
> This may need an update after discussion on the binding patch.
Yep.
Thanks for the review!
Eddie
>
> Andrew