zephyr/drivers/peci/peci_ite_it8xxx2.c

348 lines
8.8 KiB
C

/*
* Copyright (c) 2022 ITE Corporation. All Rights Reserved.
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT ite_peci_it8xxx2
#include <zephyr/drivers/gpio.h>
#include <zephyr/drivers/pinctrl.h>
#include <zephyr/drivers/peci.h>
#include <zephyr/kernel.h>
#include <errno.h>
#include <zephyr/device.h>
#include <zephyr/drivers/peci.h>
#include <soc.h>
#include <soc_dt.h>
#include <zephyr/logging/log.h>
#include <zephyr/sys/util.h>
LOG_MODULE_REGISTER(peci_ite_it8xxx2, CONFIG_PECI_LOG_LEVEL);
BUILD_ASSERT(IS_ENABLED(CONFIG_PECI_INTERRUPT_DRIVEN),
"Please enable the option CONFIG_PECI_INTERRUPT_DRIVEN");
/*
* This driver is single-instance. If the devicetree contains multiple
* instances, this will fail and the driver needs to be revisited.
*/
BUILD_ASSERT(DT_NUM_INST_STATUS_OKAY(DT_DRV_COMPAT) <= 1,
"Unsupported PECI Instance");
/* The following constants describes the bitrate of it8xxx2 PECI,
* for the frequency are 2000KHz, 1000KHz, and 1600KHz. (Unit: KHz)
*/
#define PECI_IT8XXX2_BITRATE_2MHZ 2000
#define PECI_IT8XXX2_BITRATE_1MHZ 1000
#define PECI_IT8XXX2_BITRATE_1P6MHZ 1600
/* The following masks are designed for the PECI bitrate settings,
* for the bits[7:3] are not related to this features.
*/
#define PECI_IT8XXX2_BITRATE_BITS_MASK 0x07
#define PECI_IT8XXX2_BITRATE_2MHZ_BITS 0x00
#define PECI_IT8XXX2_BITRATE_1MHZ_BITS 0x01
#define PECI_IT8XXX2_BITRATE_1P6MHZ_BITS 0x04
/* The Transaction Timeout */
#define PECI_TIMEOUT_MS 30
/* PECI interface 0 */
#define PECI0 0
/* HOSTAR (F02C00h) */
#define HOBY BIT(0)
#define FINISH BIT(1)
#define RD_FCS_ERR BIT(2)
#define WR_FCS_ERR BIT(3)
#define EXTERR BIT(5)
#define BUS_ER BIT(6)
#define TEMPERR BIT(7)
#define HOSTAR_RST_ANYBIT \
(TEMPERR|BUS_ER|EXTERR|WR_FCS_ERR|RD_FCS_ERR|FINISH)
/* HOCTLR (F02C01h) */
#define START BIT(0)
#define AWFCS_EN BIT(1)
#define CONTROL BIT(2)
#define PECIHEN BIT(3)
#define FCSERR_ABT BIT(4)
#define FIFOCLR BIT(5)
/*
* TODO: The Voltage Configuration
* Related DTSi and registers settings should be fulfilled
* in the future.
*/
/* PADCTLR (F02C0Eh) */
#define PECI_DVIE 0x04
enum peci_vtts {
HOVTTS0P85V = 0x00,
HOVTTS0P90V = 0x01,
HOVTTS0P95V = 0x02,
HOVTTS1P00V = 0x03,
HOVTTS1P05V = 0x08,
HOVTTS1P10V = 0x09,
HOVTTS1P15V = 0x0A,
HOVTTS1P20V = 0x0B,
HOVTTS1P25V = 0x10,
};
struct peci_it8xxx2_config {
uintptr_t base_addr;
uint8_t irq_no;
const struct pinctrl_dev_config *pcfg;
};
struct peci_it8xxx2_data {
struct peci_msg *msgs;
struct k_sem device_sync_sem;
uint32_t bitrate;
};
PINCTRL_DT_INST_DEFINE(0);
static const struct peci_it8xxx2_config peci_it8xxx2_config0 = {
.base_addr = DT_INST_REG_ADDR(0),
.irq_no = DT_INST_IRQN(0),
.pcfg = PINCTRL_DT_INST_DEV_CONFIG_GET(0),
};
static struct peci_it8xxx2_data peci_it8xxx2_data0;
/* ITE IT8XXX2 PECI Functions */
static void peci_it8xxx2_init_vtts(struct peci_it8xxx2_regs *reg_base,
enum peci_vtts vol_opt)
{
reg_base->PADCTLR = (reg_base->PADCTLR & PECI_DVIE) | vol_opt;
}
static void peci_it8xxx2_rst_status(struct peci_it8xxx2_regs *reg_base)
{
reg_base->HOSTAR = HOSTAR_RST_ANYBIT;
}
static int peci_it8xxx2_check_host_busy(struct peci_it8xxx2_regs *reg_base)
{
return (reg_base->HOSTAR & HOBY) ? (-EBUSY) : 0;
}
static int peci_it8xxx2_check_host_finish(const struct device *dev)
{
struct peci_it8xxx2_data *data = dev->data;
const struct peci_it8xxx2_config *config = dev->config;
struct peci_it8xxx2_regs *const peci_regs =
(struct peci_it8xxx2_regs *)config->base_addr;
int ret = k_sem_take(&data->device_sync_sem, K_MSEC(PECI_TIMEOUT_MS));
if (ret == -EAGAIN) {
LOG_ERR("%s: Timeout", __func__);
return -ETIMEDOUT;
}
if (peci_regs->HOSTAR != FINISH) {
LOG_ERR("[PECI] Error: HOSTAR=0x%02X\r\n", peci_regs->HOSTAR);
return -EIO;
}
return 0;
}
static int peci_it8xxx2_configure(const struct device *dev, uint32_t bitrate)
{
struct peci_it8xxx2_data *data = dev->data;
const struct peci_it8xxx2_config *config = dev->config;
struct peci_it8xxx2_regs *const peci_regs =
(struct peci_it8xxx2_regs *)config->base_addr;
uint8_t hoctl2r_to_write;
data->bitrate = bitrate;
hoctl2r_to_write =
(peci_regs->HOCTL2R) & (~(PECI_IT8XXX2_BITRATE_BITS_MASK));
switch (bitrate) {
case PECI_IT8XXX2_BITRATE_2MHZ:
break;
case PECI_IT8XXX2_BITRATE_1MHZ:
hoctl2r_to_write |= PECI_IT8XXX2_BITRATE_1MHZ_BITS;
break;
case PECI_IT8XXX2_BITRATE_1P6MHZ:
hoctl2r_to_write |= PECI_IT8XXX2_BITRATE_1P6MHZ_BITS;
break;
default:
LOG_ERR("[PECI] Error: Specified Bitrate Not Supported\r\n");
hoctl2r_to_write |= PECI_IT8XXX2_BITRATE_1MHZ_BITS;
data->bitrate = PECI_IT8XXX2_BITRATE_1MHZ;
peci_regs->HOCTL2R = hoctl2r_to_write;
return -ENOTSUP;
}
peci_regs->HOCTL2R = hoctl2r_to_write;
return 0;
}
static int peci_it8xxx2_enable(const struct device *dev)
{
const struct peci_it8xxx2_config *config = dev->config;
struct peci_it8xxx2_regs *const peci_regs =
(struct peci_it8xxx2_regs *)config->base_addr;
peci_regs->HOCTLR |= (FIFOCLR|FCSERR_ABT|PECIHEN|CONTROL);
return 0;
}
static int peci_it8xxx2_disable(const struct device *dev)
{
const struct peci_it8xxx2_config *config = dev->config;
struct peci_it8xxx2_regs *const peci_regs =
(struct peci_it8xxx2_regs *)config->base_addr;
peci_regs->HOCTLR &= ~(PECIHEN);
return 0;
}
static void peci_it8xxx2_rst_module(const struct device *dev)
{
const struct peci_it8xxx2_config *config = dev->config;
struct peci_it8xxx2_regs *const peci_regs =
(struct peci_it8xxx2_regs *)config->base_addr;
LOG_ERR("[PECI] Module Reset for Status Error.\r\n");
/* Reset IT8XXX2 PECI Module Thoroughly */
IT83XX_GCTRL_RSTC4 |= RPECI;
/*
* Due to the fact that we've checked if the peci_enable()
* called before calling the peci_transfer(), so the peci
* were definitely enabled before the error occurred.
* Here is the recovery mechanism for recovering the PECI
* bus when the errors occur.
*/
peci_regs->PADCTLR |= PECI_DVIE;
peci_it8xxx2_init_vtts(peci_regs, HOVTTS0P95V);
peci_it8xxx2_configure(dev, PECI_IT8XXX2_BITRATE_1MHZ);
peci_it8xxx2_enable(dev);
LOG_ERR("[PECI] Reinitialization Finished.\r\n");
}
static int peci_it8xxx2_transfer(const struct device *dev, struct peci_msg *msg)
{
const struct peci_it8xxx2_config *config = dev->config;
struct peci_it8xxx2_regs *const peci_regs =
(struct peci_it8xxx2_regs *)config->base_addr;
struct peci_buf *peci_rx_buf = &msg->rx_buffer;
struct peci_buf *peci_tx_buf = &msg->tx_buffer;
int cnt, ret_code;
ret_code = 0;
if (!(peci_regs->HOCTLR & PECIHEN)) {
LOG_ERR("[PECI] Please call the peci_enable() first.\r\n");
return -ECONNREFUSED;
}
if (peci_it8xxx2_check_host_busy(peci_regs) != 0) {
return -EBUSY;
}
peci_regs->HOTRADDR = msg->addr;
peci_regs->HOWRLR = peci_tx_buf->len;
peci_regs->HORDLR = peci_rx_buf->len;
peci_regs->HOCMDR = msg->cmd_code;
if (msg->cmd_code != PECI_CMD_PING) {
for (cnt = 0; cnt < (peci_tx_buf->len - 1); cnt++) {
peci_regs->HOWRDR = peci_tx_buf->buf[cnt];
}
}
/* Host Available */
irq_enable(config->irq_no);
peci_regs->HOCTLR |= START;
ret_code = peci_it8xxx2_check_host_finish(dev);
if (!ret_code) {
/* Host Transactions Finished, Fetch Data from the regs */
if (peci_rx_buf->len) {
for (cnt = 0; cnt < (peci_rx_buf->len); cnt++) {
peci_rx_buf->buf[cnt] = peci_regs->HORDDR;
}
}
peci_it8xxx2_rst_status(peci_regs);
} else {
/* Host Transactions Failure */
peci_it8xxx2_rst_module(dev);
}
return (ret_code);
}
static void peci_it8xxx2_isr(const struct device *dev)
{
struct peci_it8xxx2_data *data = dev->data;
const struct peci_it8xxx2_config *config = dev->config;
irq_disable(config->irq_no);
k_sem_give(&data->device_sync_sem);
}
static const struct peci_driver_api peci_it8xxx2_driver_api = {
.config = peci_it8xxx2_configure,
.enable = peci_it8xxx2_enable,
.disable = peci_it8xxx2_disable,
.transfer = peci_it8xxx2_transfer,
};
static int peci_it8xxx2_init(const struct device *dev)
{
struct peci_it8xxx2_data *data = dev->data;
const struct peci_it8xxx2_config *config = dev->config;
struct peci_it8xxx2_regs *const peci_regs =
(struct peci_it8xxx2_regs *)config->base_addr;
int status;
/* Initialize Semaphore */
k_sem_init(&data->device_sync_sem, 0, 1);
/* Configure the GPF6 to Alternative Function 3: PECI */
status = pinctrl_apply_state(config->pcfg, PINCTRL_STATE_DEFAULT);
if (status < 0) {
LOG_ERR("Failed to configure PECI pins");
return status;
}
peci_regs->PADCTLR |= PECI_DVIE;
peci_it8xxx2_init_vtts(peci_regs, HOVTTS0P95V);
peci_it8xxx2_configure(dev, PECI_IT8XXX2_BITRATE_1MHZ);
/* Interrupt Assignment */
IRQ_CONNECT(DT_INST_IRQN(0),
0,
peci_it8xxx2_isr,
DEVICE_DT_INST_GET(0),
0);
return 0;
}
DEVICE_DT_INST_DEFINE(0,
&peci_it8xxx2_init,
NULL,
&peci_it8xxx2_data0,
&peci_it8xxx2_config0,
POST_KERNEL, CONFIG_PECI_INIT_PRIORITY,
&peci_it8xxx2_driver_api);