diff options
Diffstat (limited to 'drivers/mailbox/scpi_protocol.c')
| -rw-r--r-- | drivers/mailbox/scpi_protocol.c | 353 |
1 files changed, 353 insertions, 0 deletions
diff --git a/drivers/mailbox/scpi_protocol.c b/drivers/mailbox/scpi_protocol.c new file mode 100644 index 000000000000..edcf47ea06ab --- /dev/null +++ b/drivers/mailbox/scpi_protocol.c @@ -0,0 +1,353 @@ +/* + * System Control and Power Interface (SCPI) Message Protocol driver + * + * Copyright (C) 2014 ARM Ltd. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/err.h> +#include <linux/export.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/printk.h> +#include <linux/mailbox_client.h> +#include <linux/scpi_protocol.h> +#include <linux/slab.h> + +#include "arm_mhu.h" + +#define CMD_ID_SHIFT 0 +#define CMD_ID_MASK 0xff +#define CMD_SENDER_ID_SHIFT 8 +#define CMD_SENDER_ID_MASK 0xff +#define CMD_DATA_SIZE_SHIFT 20 +#define CMD_DATA_SIZE_MASK 0x1ff +#define PACK_SCPI_CMD(cmd, sender, txsz) \ + ((((cmd) & CMD_ID_MASK) << CMD_ID_SHIFT) | \ + (((sender) & CMD_SENDER_ID_MASK) << CMD_SENDER_ID_SHIFT) | \ + (((txsz) & CMD_DATA_SIZE_MASK) << CMD_DATA_SIZE_SHIFT)) + +#define MAX_DVFS_DOMAINS 3 +#define MAX_DVFS_OPPS 4 +#define DVFS_LATENCY(hdr) ((hdr) >> 16) +#define DVFS_OPP_COUNT(hdr) (((hdr) >> 8) & 0xff) + +enum scpi_error_codes { + SCPI_SUCCESS = 0, /* Success */ + SCPI_ERR_PARAM = 1, /* Invalid parameter(s) */ + SCPI_ERR_ALIGN = 2, /* Invalid alignment */ + SCPI_ERR_SIZE = 3, /* Invalid size */ + SCPI_ERR_HANDLER = 4, /* Invalid handler/callback */ + SCPI_ERR_ACCESS = 5, /* Invalid access/permission denied */ + SCPI_ERR_RANGE = 6, /* Value out of range */ + SCPI_ERR_TIMEOUT = 7, /* Timeout has occurred */ + SCPI_ERR_NOMEM = 8, /* Invalid memory area or pointer */ + SCPI_ERR_PWRSTATE = 9, /* Invalid power state */ + SCPI_ERR_SUPPORT = 10, /* Not supported or disabled */ + SCPI_ERR_DEVICE = 11, /* Device error */ + SCPI_ERR_MAX +}; + +enum scpi_client_id { + SCPI_CL_NONE, + SCPI_CL_CLOCKS, + SCPI_CL_DVFS, + SCPI_CL_POWER, + SCPI_MAX, +}; + +enum scpi_std_cmd { + SCPI_CMD_INVALID = 0x00, + SCPI_CMD_SCPI_READY = 0x01, + SCPI_CMD_SCPI_CAPABILITIES = 0x02, + SCPI_CMD_EVENT = 0x03, + SCPI_CMD_SET_CSS_PWR_STATE = 0x04, + SCPI_CMD_GET_CSS_PWR_STATE = 0x05, + SCPI_CMD_CFG_PWR_STATE_STAT = 0x06, + SCPI_CMD_GET_PWR_STATE_STAT = 0x07, + SCPI_CMD_SYS_PWR_STATE = 0x08, + SCPI_CMD_L2_READY = 0x09, + SCPI_CMD_SET_AP_TIMER = 0x0a, + SCPI_CMD_CANCEL_AP_TIME = 0x0b, + SCPI_CMD_DVFS_CAPABILITIES = 0x0c, + SCPI_CMD_GET_DVFS_INFO = 0x0d, + SCPI_CMD_SET_DVFS = 0x0e, + SCPI_CMD_GET_DVFS = 0x0f, + SCPI_CMD_GET_DVFS_STAT = 0x10, + SCPI_CMD_SET_RTC = 0x11, + SCPI_CMD_GET_RTC = 0x12, + SCPI_CMD_CLOCK_CAPABILITIES = 0x13, + SCPI_CMD_SET_CLOCK_INDEX = 0x14, + SCPI_CMD_SET_CLOCK_VALUE = 0x15, + SCPI_CMD_GET_CLOCK_VALUE = 0x16, + SCPI_CMD_PSU_CAPABILITIES = 0x17, + SCPI_CMD_SET_PSU = 0x18, + SCPI_CMD_GET_PSU = 0x19, + SCPI_CMD_SENSOR_CAPABILITIES = 0x1a, + SCPI_CMD_SENSOR_INFO = 0x1b, + SCPI_CMD_SENSOR_VALUE = 0x1c, + SCPI_CMD_SENSOR_CFG_PERIODIC = 0x1d, + SCPI_CMD_SENSOR_CFG_BOUNDS = 0x1e, + SCPI_CMD_SENSOR_ASYNC_VALUE = 0x1f, + SCPI_CMD_COUNT +}; + +struct scpi_data_buf { + int client_id; + struct mhu_data_buf *data; + struct completion complete; +}; + +static int high_priority_cmds[] = { + SCPI_CMD_GET_CSS_PWR_STATE, + SCPI_CMD_CFG_PWR_STATE_STAT, + SCPI_CMD_GET_PWR_STATE_STAT, + SCPI_CMD_SET_DVFS, + SCPI_CMD_GET_DVFS, + SCPI_CMD_SET_RTC, + SCPI_CMD_GET_RTC, + SCPI_CMD_SET_CLOCK_INDEX, + SCPI_CMD_SET_CLOCK_VALUE, + SCPI_CMD_GET_CLOCK_VALUE, + SCPI_CMD_SET_PSU, + SCPI_CMD_GET_PSU, + SCPI_CMD_SENSOR_VALUE, + SCPI_CMD_SENSOR_CFG_PERIODIC, + SCPI_CMD_SENSOR_CFG_BOUNDS, +}; + +static struct scpi_opp *scpi_opps[MAX_DVFS_DOMAINS]; + +static int scpi_linux_errmap[SCPI_ERR_MAX] = { + 0, -EINVAL, -ENOEXEC, -EMSGSIZE, + -EINVAL, -EACCES, -ERANGE, -ETIMEDOUT, + -ENOMEM, -EINVAL, -EOPNOTSUPP, -EIO, +}; + +static inline int scpi_to_linux_errno(int errno) +{ + if (errno >= SCPI_SUCCESS && errno < SCPI_ERR_MAX) + return scpi_linux_errmap[errno]; + return -EIO; +} + +static bool high_priority_chan_supported(int cmd) +{ + int idx; + for (idx = 0; idx < ARRAY_SIZE(high_priority_cmds); idx++) + if (cmd == high_priority_cmds[idx]) + return true; + return false; +} + +static void scpi_rx_callback(struct mbox_client *cl, void *msg) +{ + struct mhu_data_buf *data = (struct mhu_data_buf *)msg; + struct scpi_data_buf *scpi_buf = data->cl_data; + complete(&scpi_buf->complete); +} + +static int send_scpi_cmd(struct scpi_data_buf *scpi_buf, bool high_priority) +{ + struct mbox_chan *chan; + struct mbox_client cl; + struct mhu_data_buf *data = scpi_buf->data; + u32 status; + + cl.dev = the_scpi_device; + cl.rx_callback = scpi_rx_callback; + cl.tx_done = NULL; + cl.tx_block = false; + cl.knows_txdone = false; + cl.chan_name = high_priority ? + CHANNEL_HIGH_PRIORITY : + CHANNEL_LOW_PRIORITY; + + chan = mbox_request_channel(&cl); + if (IS_ERR(chan)) + return PTR_ERR(chan); + + init_completion(&scpi_buf->complete); + if (mbox_send_message(chan, (void *)data) < 0) { + status = SCPI_ERR_TIMEOUT; + goto free_channel; + } + + wait_for_completion(&scpi_buf->complete); + status = *(u32 *)(data->rx_buf); /* read first word */ + +free_channel: + mbox_free_channel(chan); + + return scpi_to_linux_errno(status); +} + +#define SCPI_SETUP_DBUF(scpi_buf, mhu_buf, _client_id,\ + _cmd, _tx_buf, _rx_buf) \ +do { \ + struct mhu_data_buf *pdata = &mhu_buf; \ + pdata->cmd = _cmd; \ + pdata->tx_buf = &_tx_buf; \ + pdata->tx_size = sizeof(_tx_buf); \ + pdata->rx_buf = &_rx_buf; \ + pdata->rx_size = sizeof(_rx_buf); \ + scpi_buf.client_id = _client_id; \ + scpi_buf.data = pdata; \ +} while (0) + +static int scpi_execute_cmd(struct scpi_data_buf *scpi_buf) +{ + struct mhu_data_buf *data; + bool high_priority; + + if (!scpi_buf || !scpi_buf->data) + return -EINVAL; + + data = scpi_buf->data; + high_priority = high_priority_chan_supported(data->cmd); + data->cmd = PACK_SCPI_CMD(data->cmd, scpi_buf->client_id, + data->tx_size); + data->cl_data = scpi_buf; + + return send_scpi_cmd(scpi_buf, high_priority); +} + +unsigned long scpi_clk_get_val(u16 clk_id) +{ + struct scpi_data_buf sdata; + struct mhu_data_buf mdata; + struct __packed { + u32 status; + u32 clk_rate; + } buf; + + SCPI_SETUP_DBUF(sdata, mdata, SCPI_CL_CLOCKS, + SCPI_CMD_GET_CLOCK_VALUE, clk_id, buf); + if (scpi_execute_cmd(&sdata)) + return 0; + + return buf.clk_rate; +} +EXPORT_SYMBOL_GPL(scpi_clk_get_val); + +int scpi_clk_set_val(u16 clk_id, unsigned long rate) +{ + struct scpi_data_buf sdata; + struct mhu_data_buf mdata; + int stat; + struct __packed { + u32 clk_rate; + u16 clk_id; + } buf; + + buf.clk_rate = (u32)rate; + buf.clk_id = clk_id; + + SCPI_SETUP_DBUF(sdata, mdata, SCPI_CL_CLOCKS, + SCPI_CMD_SET_CLOCK_VALUE, buf, stat); + return scpi_execute_cmd(&sdata); +} +EXPORT_SYMBOL_GPL(scpi_clk_set_val); + +struct scpi_opp *scpi_dvfs_get_opps(u8 domain) +{ + struct scpi_data_buf sdata; + struct mhu_data_buf mdata; + struct __packed { + u32 status; + u32 header; + u32 freqs[MAX_DVFS_OPPS]; + } buf; + struct scpi_opp *opp; + size_t freqs_sz; + int count, ret; + + if (domain >= MAX_DVFS_DOMAINS) + return ERR_PTR(-EINVAL); + + if (scpi_opps[domain]) /* data already populated */ + return scpi_opps[domain]; + + SCPI_SETUP_DBUF(sdata, mdata, SCPI_CL_DVFS, + SCPI_CMD_GET_DVFS_INFO, domain, buf); + ret = scpi_execute_cmd(&sdata); + if (ret) + return ERR_PTR(ret); + + opp = kmalloc(sizeof(*opp), GFP_KERNEL); + if (!opp) + return ERR_PTR(-ENOMEM); + + count = DVFS_OPP_COUNT(buf.header); + freqs_sz = count * sizeof(*(opp->freqs)); + + opp->count = count; + opp->latency = DVFS_LATENCY(buf.header); + opp->freqs = kmalloc(freqs_sz, GFP_KERNEL); + if (!opp->freqs) { + kfree(opp); + return ERR_PTR(-ENOMEM); + } + + memcpy(opp->freqs, &buf.freqs[0], freqs_sz); + scpi_opps[domain] = opp; + + return opp; +} +EXPORT_SYMBOL_GPL(scpi_dvfs_get_opps); + +int scpi_dvfs_get_idx(u8 domain) +{ + struct scpi_data_buf sdata; + struct mhu_data_buf mdata; + struct __packed { + u32 status; + u8 dvfs_idx; + } buf; + int ret; + + if (domain >= MAX_DVFS_DOMAINS) + return -EINVAL; + + SCPI_SETUP_DBUF(sdata, mdata, SCPI_CL_DVFS, + SCPI_CMD_GET_DVFS, domain, buf); + ret = scpi_execute_cmd(&sdata); + + if (!ret) + ret = buf.dvfs_idx; + return ret; +} +EXPORT_SYMBOL_GPL(scpi_dvfs_get_idx); + +int scpi_dvfs_set_idx(u8 domain, u8 idx) +{ + struct scpi_data_buf sdata; + struct mhu_data_buf mdata; + struct __packed { + u8 dvfs_domain; + u8 dvfs_idx; + } buf; + int stat; + + buf.dvfs_idx = idx; + buf.dvfs_domain = domain; + + if (domain >= MAX_DVFS_DOMAINS) + return -EINVAL; + + SCPI_SETUP_DBUF(sdata, mdata, SCPI_CL_DVFS, + SCPI_CMD_SET_DVFS, buf, stat); + return scpi_execute_cmd(&sdata); +} +EXPORT_SYMBOL_GPL(scpi_dvfs_set_idx); |