From 2c3c1048746a4622d8c89a29670120dc8fab93c4 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 20:49:45 +0200 Subject: Adding upstream version 6.1.76. Signed-off-by: Daniel Baumann --- drivers/hwmon/occ/p8_i2c.c | 257 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 257 insertions(+) create mode 100644 drivers/hwmon/occ/p8_i2c.c (limited to 'drivers/hwmon/occ/p8_i2c.c') diff --git a/drivers/hwmon/occ/p8_i2c.c b/drivers/hwmon/occ/p8_i2c.c new file mode 100644 index 000000000..9e1744fcc --- /dev/null +++ b/drivers/hwmon/occ/p8_i2c.c @@ -0,0 +1,257 @@ +// SPDX-License-Identifier: GPL-2.0+ +// Copyright IBM Corp 2019 + +#include +#include +#include +#include +#include +#include +#include +#include + +#include "common.h" + +#define OCC_TIMEOUT_MS 1000 +#define OCC_CMD_IN_PRG_WAIT_MS 50 + +/* OCB (on-chip control bridge - interface to OCC) registers */ +#define OCB_DATA1 0x6B035 +#define OCB_ADDR 0x6B070 +#define OCB_DATA3 0x6B075 + +/* OCC SRAM address space */ +#define OCC_SRAM_ADDR_CMD 0xFFFF6000 +#define OCC_SRAM_ADDR_RESP 0xFFFF7000 + +#define OCC_DATA_ATTN 0x20010000 + +struct p8_i2c_occ { + struct occ occ; + struct i2c_client *client; +}; + +#define to_p8_i2c_occ(x) container_of((x), struct p8_i2c_occ, occ) + +static int p8_i2c_occ_getscom(struct i2c_client *client, u32 address, u8 *data) +{ + ssize_t rc; + __be64 buf; + struct i2c_msg msgs[2]; + + /* p8 i2c slave requires shift */ + address <<= 1; + + msgs[0].addr = client->addr; + msgs[0].flags = client->flags & I2C_M_TEN; + msgs[0].len = sizeof(u32); + /* address is a scom address; bus-endian */ + msgs[0].buf = (char *)&address; + + /* data from OCC is big-endian */ + msgs[1].addr = client->addr; + msgs[1].flags = (client->flags & I2C_M_TEN) | I2C_M_RD; + msgs[1].len = sizeof(u64); + msgs[1].buf = (char *)&buf; + + rc = i2c_transfer(client->adapter, msgs, 2); + if (rc < 0) + return rc; + + *(u64 *)data = be64_to_cpu(buf); + + return 0; +} + +static int p8_i2c_occ_putscom(struct i2c_client *client, u32 address, u8 *data) +{ + u32 buf[3]; + ssize_t rc; + + /* p8 i2c slave requires shift */ + address <<= 1; + + /* address is bus-endian; data passed through from user as-is */ + buf[0] = address; + memcpy(&buf[1], &data[4], sizeof(u32)); + memcpy(&buf[2], data, sizeof(u32)); + + rc = i2c_master_send(client, (const char *)buf, sizeof(buf)); + if (rc < 0) + return rc; + else if (rc != sizeof(buf)) + return -EIO; + + return 0; +} + +static int p8_i2c_occ_putscom_u32(struct i2c_client *client, u32 address, + u32 data0, u32 data1) +{ + u8 buf[8]; + + memcpy(buf, &data0, 4); + memcpy(buf + 4, &data1, 4); + + return p8_i2c_occ_putscom(client, address, buf); +} + +static int p8_i2c_occ_putscom_be(struct i2c_client *client, u32 address, + u8 *data, size_t len) +{ + __be32 data0 = 0, data1 = 0; + + memcpy(&data0, data, min_t(size_t, len, 4)); + if (len > 4) { + len -= 4; + memcpy(&data1, data + 4, min_t(size_t, len, 4)); + } + + return p8_i2c_occ_putscom_u32(client, address, be32_to_cpu(data0), + be32_to_cpu(data1)); +} + +static int p8_i2c_occ_send_cmd(struct occ *occ, u8 *cmd, size_t len, + void *resp, size_t resp_len) +{ + int i, rc; + unsigned long start; + u16 data_length; + const unsigned long timeout = msecs_to_jiffies(OCC_TIMEOUT_MS); + const long wait_time = msecs_to_jiffies(OCC_CMD_IN_PRG_WAIT_MS); + struct p8_i2c_occ *ctx = to_p8_i2c_occ(occ); + struct i2c_client *client = ctx->client; + struct occ_response *or = (struct occ_response *)resp; + + start = jiffies; + + /* set sram address for command */ + rc = p8_i2c_occ_putscom_u32(client, OCB_ADDR, OCC_SRAM_ADDR_CMD, 0); + if (rc) + return rc; + + /* write command (expected to already be BE), we need bus-endian... */ + rc = p8_i2c_occ_putscom_be(client, OCB_DATA3, cmd, len); + if (rc) + return rc; + + /* trigger OCC attention */ + rc = p8_i2c_occ_putscom_u32(client, OCB_DATA1, OCC_DATA_ATTN, 0); + if (rc) + return rc; + + do { + /* set sram address for response */ + rc = p8_i2c_occ_putscom_u32(client, OCB_ADDR, + OCC_SRAM_ADDR_RESP, 0); + if (rc) + return rc; + + rc = p8_i2c_occ_getscom(client, OCB_DATA3, (u8 *)resp); + if (rc) + return rc; + + /* wait for OCC */ + if (or->return_status == OCC_RESP_CMD_IN_PRG) { + rc = -EALREADY; + + if (time_after(jiffies, start + timeout)) + break; + + set_current_state(TASK_INTERRUPTIBLE); + schedule_timeout(wait_time); + } + } while (rc); + + /* check the OCC response */ + switch (or->return_status) { + case OCC_RESP_CMD_IN_PRG: + rc = -ETIMEDOUT; + break; + case OCC_RESP_SUCCESS: + rc = 0; + break; + case OCC_RESP_CMD_INVAL: + case OCC_RESP_CMD_LEN_INVAL: + case OCC_RESP_DATA_INVAL: + case OCC_RESP_CHKSUM_ERR: + rc = -EINVAL; + break; + case OCC_RESP_INT_ERR: + case OCC_RESP_BAD_STATE: + case OCC_RESP_CRIT_EXCEPT: + case OCC_RESP_CRIT_INIT: + case OCC_RESP_CRIT_WATCHDOG: + case OCC_RESP_CRIT_OCB: + case OCC_RESP_CRIT_HW: + rc = -EREMOTEIO; + break; + default: + rc = -EPROTO; + } + + if (rc < 0) + return rc; + + data_length = get_unaligned_be16(&or->data_length); + if ((data_length + 7) > resp_len) + return -EMSGSIZE; + + /* fetch the rest of the response data */ + for (i = 8; i < data_length + 7; i += 8) { + rc = p8_i2c_occ_getscom(client, OCB_DATA3, ((u8 *)resp) + i); + if (rc) + return rc; + } + + return 0; +} + +static int p8_i2c_occ_probe(struct i2c_client *client) +{ + struct occ *occ; + struct p8_i2c_occ *ctx = devm_kzalloc(&client->dev, sizeof(*ctx), + GFP_KERNEL); + if (!ctx) + return -ENOMEM; + + ctx->client = client; + occ = &ctx->occ; + occ->bus_dev = &client->dev; + dev_set_drvdata(&client->dev, occ); + + occ->powr_sample_time_us = 250; + occ->poll_cmd_data = 0x10; /* P8 OCC poll data */ + occ->send_cmd = p8_i2c_occ_send_cmd; + + return occ_setup(occ); +} + +static void p8_i2c_occ_remove(struct i2c_client *client) +{ + struct occ *occ = dev_get_drvdata(&client->dev); + + occ_shutdown(occ); +} + +static const struct of_device_id p8_i2c_occ_of_match[] = { + { .compatible = "ibm,p8-occ-hwmon" }, + {} +}; +MODULE_DEVICE_TABLE(of, p8_i2c_occ_of_match); + +static struct i2c_driver p8_i2c_occ_driver = { + .class = I2C_CLASS_HWMON, + .driver = { + .name = "occ-hwmon", + .of_match_table = p8_i2c_occ_of_match, + }, + .probe_new = p8_i2c_occ_probe, + .remove = p8_i2c_occ_remove, +}; + +module_i2c_driver(p8_i2c_occ_driver); + +MODULE_AUTHOR("Eddie James "); +MODULE_DESCRIPTION("BMC P8 OCC hwmon driver"); +MODULE_LICENSE("GPL"); -- cgit v1.2.3