// SPDX-License-Identifier: GPL-2.0
/*
* Silvaco dual-role I3C master driver
*
* Copyright (C) 2020 Silvaco
* Author: Miquel RAYNAL <miquel.raynal@bootlin.com>
* Based on a work from: Conor Culhane <conor.culhane@silvaco.com>
*/
#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/completion.h>
#include <linux/errno.h>
#include <linux/i3c/master.h>
#include <linux/interrupt.h>
#include <linux/iopoll.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
/* Master Mode Registers */
#define SVC_I3C_MCONFIG 0x000
#define SVC_I3C_MCONFIG_MASTER_EN BIT(0)
#define SVC_I3C_MCONFIG_DISTO(x) FIELD_PREP(BIT(3), (x))
#define SVC_I3C_MCONFIG_HKEEP(x) FIELD_PREP(GENMASK(5, 4), (x))
#define SVC_I3C_MCONFIG_ODSTOP(x) FIELD_PREP(BIT(6), (x))
#define SVC_I3C_MCONFIG_PPBAUD(x) FIELD_PREP(GENMASK(11, 8), (x))
#define SVC_I3C_MCONFIG_PPLOW(x) FIELD_PREP(GENMASK(15, 12), (x))
#define SVC_I3C_MCONFIG_ODBAUD(x) FIELD_PREP(GENMASK(23, 16), (x))
#define SVC_I3C_MCONFIG_ODHPP(x) FIELD_PREP(BIT(24), (x))
#define SVC_I3C_MCONFIG_SKEW(x) FIELD_PREP(GENMASK(27, 25), (x))
#define SVC_I3C_MCONFIG_I2CBAUD(x) FIELD_PREP(GENMASK(31, 28), (x))
#define SVC_I3C_MCTRL 0x084
#define SVC_I3C_MCTRL_REQUEST_MASK GENMASK(2, 0)
#define SVC_I3C_MCTRL_REQUEST_NONE 0
#define SVC_I3C_MCTRL_REQUEST_START_ADDR 1
#define SVC_I3C_MCTRL_REQUEST_STOP 2
#define SVC_I3C_MCTRL_REQUEST_IBI_ACKNACK 3
#define SVC_I3C_MCTRL_REQUEST_PROC_DAA 4
#define SVC_I3C_MCTRL_REQUEST_AUTO_IBI 7
#define SVC_I3C_MCTRL_TYPE_I3C 0
#define SVC_I3C_MCTRL_TYPE_I2C BIT(4)
#define SVC_I3C_MCTRL_IBIRESP_AUTO 0
#define SVC_I3C_MCTRL_IBIRESP_ACK_WITHOUT_BYTE 0
#define SVC_I3C_MCTRL_IBIRESP_ACK_WITH_BYTE BIT(7)
#define SVC_I3C_MCTRL_IBIRESP_NACK BIT(6)
#define SVC_I3C_MCTRL_IBIRESP_MANUAL GENMASK(7, 6)
#define SVC_I3C_MCTRL_DIR(x) FIELD_PREP(BIT(8), (x))
#define SVC_I3C_MCTRL_DIR_WRITE 0
#define SVC_I3C_MCTRL_DIR_READ 1
#define SVC_I3C_MCTRL_ADDR(x) FIELD_PREP(GENMASK(15, 9), (x))
#define SVC_I3C_MCTRL_RDTERM(x) FIELD_PREP(GENMASK(23, 16), (x))
#define SVC_I3C_MSTATUS 0x088
#define SVC_I3C_MSTATUS_STATE(x) FIELD_GET(GENMASK(2, 0), (x))
#define SVC_I3C_MSTATUS_STATE_DAA(x) (SVC_I3C_MSTATUS_STATE(x) == 5)
#define SVC_I3C_MSTATUS_STATE_IDLE(x) (SVC_I3C_MSTATUS_STATE(x) == 0)
#define SVC_I3C_MSTATUS_BETWEEN(x) FIELD_GET(BIT(4), (x))
#define SVC_I3C_MSTATUS_NACKED(x) FIELD_GET(BIT(5), (x))
#define SVC_I3C_MSTATUS_IBITYPE(x) FIELD_GET(GENMASK(7, 6), (x))
#define SVC_I3C_MSTATUS_IBITYPE_IBI 1
#define SVC_I3C_MSTATUS_IBITYPE_MASTER_REQUEST 2
#define SVC_I3C_MSTATUS_IBITYPE_HOT_JOIN 3
#define SVC_I3C_MINT_SLVSTART BIT(8)
#define SVC_I3C_MINT_MCTRLDONE BIT(9)
#define SVC_I3C_MINT_COMPLETE BIT(10)
#define SVC_I3C_MINT_RXPEND BIT(11)
#define SVC_I3C_MINT_TXNOTFULL BIT(12)
#define SVC_I3C_MINT_IBIWON BIT(13)
#define SVC_I3C_MINT_ERRWARN BIT(15)
#define SVC_I3C_MSTATUS_SLVSTART(x) FIELD_GET(SVC_I3C_MINT_SLVSTART, (x))
#define SVC_I3C_MSTATUS_MCTRLDONE(x) FIELD_GET(SVC_I3C_MINT_MCTRLDONE, (x))
#define SVC_I3C_MSTATUS_COMPLETE(x) FIELD_GET(SVC_I3C_MINT_COMPLETE, (x))
#define SVC_I3C_MSTATUS_RXPEND(x) FIELD_GET(SVC_I3C_MINT_RXPEND, (x))
#define SVC_I3C_MSTATUS_TXNOTFULL(x) FIELD_GET(SVC_I3C_MINT_TXNOTFULL, (x))
#define SVC_I3C_MSTATUS_IBIWON(x) FIELD_GET(SVC_I3C_MINT_IBIWON, (x))
#define SVC_I3C_MSTATUS_ERRWARN(x) FIELD_GET(SVC_I3C_MINT_ERRWARN, (x))
#define SVC_I3C_MSTATUS_IBIADDR(x) FIELD_GET(GENMASK(30, 24), (x))
#define SVC_I3C_IBIRULES 0x08C
#define SVC_I3C_IBIRULES_ADDR(slot, addr) FIELD_PREP(GENMASK(29, 0), \
((addr) & 0x3F) << ((slot) * 6))
#define SVC_I3C_IBIRULES_ADDRS 5
#define SVC_I3C_IBIRULES_MSB0 BIT(30)
#define SVC_I3C_IBIRULES_NOBYTE BIT(31)
#define SVC_I3C_IBIRULES_MANDBYTE 0
#define SVC_I3C_MINTSET 0x090
#define SVC_I3C_MINTCLR 0x094
#define SVC_I3C_MINTMASKED 0x098
#define SVC_I3C_MERRWARN 0x09C
#define SVC_I3C_MERRWARN_NACK BIT(2)
#define SVC_I3C_MERRWARN_TIMEOUT BIT(20)
#define SVC_I3C_MDMACTRL 0x0A0
#define SVC_I3C_MDATACTRL 0x0AC
#define SVC_I3C_MDATACTRL_FLUSHTB BIT(0)
#define SVC_I3C_MDATACTRL_FLUSHRB BIT(1)
#define SVC_I3C_MDATACTRL_UNLOCK_TRIG BIT(3)
#define SVC_I3C_MDATACTRL_TXTRIG_FIFO_NOT_FULL GENMASK(5, 4)
#define SVC_I3C_MDATACTRL_RXTRIG_FIFO_NOT_EMPTY 0
#define SVC_I3C_MDATACTRL_RXCOUNT(x) FIELD_GET(GENMASK(28, 24), (x))
#define SVC_I3C_MDATACTRL_TXFULL BIT(30)
#define SVC_I3C_MDATACTRL_RXEMPTY BIT(31)
#define SVC_I3C_MWDATAB 0x0B0
#define SVC_I3C_MWDATAB_END BIT(8)
#define SVC_I3C_MWDATABE 0x0B4
#define SVC_I3C_MWDATAH 0x0B8
#define SVC_I3C_MWDATAHE 0x0BC
#define SVC_I3C_MRDATAB 0x0C0
#define SVC_I3C_MRDATAH 0x0C8
#define SVC_I3C_MWMSG_SDR 0x0D0
#define SVC_I3C_MRMSG_SDR 0x0D4
#define SVC_I3C_MWMSG_DDR 0x0D8
#define SVC_I3C_MRMSG_DDR 0x0DC
#define SVC_I3C_MDYNADDR 0x0E4
#define SVC_MDYNADDR_VALID BIT(0)
#define SVC_MDYNADDR_ADDR(x) FIELD_PREP(GENMASK(7, 1), (x))
#define SVC_I3C_MAX_DEVS 32
#define SVC_I3C_PM_TIMEOUT_MS 1000
/* This parameter depends on the implementation and may be tuned */
#define SVC_I3C_FIFO_SIZE 16
#define SVC_I3C_PPBAUD_MAX 15
#define SVC_I3C_QUICK_I2C_CLK 4170000
#define SVC_I3C_EVENT_IBI BIT(0)
#define SVC_I3C_EVENT_HOTJOIN BIT(1)
struct svc_i3c_cmd {
u8 addr;
bool rnw;
u8 *in;
const void *out;
unsigned int len;
unsigned int actual_len;
struct i3c_priv_xfer *xfer;
bool continued;
};
struct svc_i3c_xfer {
struct list_head node;
struct completion comp;
int ret;
unsigned int type;
unsigned int ncmds;
struct svc_i3c_cmd cmds[] __counted_by(ncmds);
};
struct svc_i3c_regs_save {
u32 mconfig;
u32 mdynaddr;
};
/**
* struct svc_i3c_master - Silvaco I3C Master structure
* @base: I3C master controller
* @dev: Corresponding device
* @regs: Memory mapping
* @saved_regs: Volatile values for PM operations
* @free_slots: Bit array of available slots
* @addrs: Array containing the dynamic addresses of each attached device
* @descs: Array of descriptors, one per attached device
* @hj_work: Hot-join work
* @ibi_work: IBI work
* @irq: Main interrupt
* @pclk: System clock
* @fclk: Fast clock (bus)
* @sclk: Slow clock (other events)
* @xferqueue: Transfer queue structure
* @xferqueue.list: List member
* @xferqueue.cur: Current ongoing transfer
* @xferqueue.lock: Queue lock
* @ibi: IBI structure
* @ibi.num_slots: Number of slots available in @ibi.slots
* @ibi.slots: Available IBI slots
* @ibi.tbq_slot: To be queued IBI slot
* @ibi.lock: IBI lock
* @lock: Transfer lock, protect between IBI work thread and callbacks from master
* @enabled_events: Bit masks for enable events (IBI, HotJoin).
* @mctrl_config: Configuration value in SVC_I3C_MCTRL for setting speed back.
*/
struct svc_i3c_master {
struct i3c_master_controller base;
struct device *dev;
void __iomem *regs;
struct svc_i3c_regs_save saved_regs;
u32 free_slots;
u8 addrs[SVC_I3C_MAX_DEVS];
struct i3c_dev_desc *descs[SVC_I3C_MAX_DEVS];
struct work_struct hj_work;
struct work_struct ibi_work;
int irq;
struct clk *pclk;
struct clk *fclk;
struct clk *sclk;
struct {
struct list_head list;
struct svc_i3c_xfer *cur;
/* Prevent races between transfers */
spinlock_t lock;
} xferqueue;
struct {
unsigned int num_slots;
struct i3c_dev_desc **slots;
struct i3c_ibi_slot *tbq_slot;
/* Prevent races within IBI handlers */
spinlock_t lock;
} ibi;
struct mutex lock;
int enabled_events;
u32 mctrl_config;
};
/**
* struct svc_i3c_i2c_dev_data - Device specific data
* @index: Index in the master tables corresponding to this device
* @ibi: IBI slot index in the master structure
* @ibi_pool: IBI pool associated to this device
*/
struct svc_i3c_i2c_dev_data {
u8 index;
int ibi;
struct i3c_generic_ibi_pool *ibi_pool;
};
static inline bool is_events_enabled(struct svc_i3c_master *master, u32 mask)
{
return !!(master->enabled_events & mask);
}
static bool svc_i3c_master_error(struct svc_i3c_master *master)
{
u32 mstatus, merrwarn;
mstatus = readl(master->regs + SVC_I3C_MSTATUS);
if (SVC_I3C_MSTATUS_ERRWARN(mstatus)) {
merrwarn = readl(master->regs + SVC_I3C_MERRWARN);
writel(merrwarn, master->regs + SVC_I3C_MERRWARN);
/* Ignore timeout error */
if (merrwarn & SVC_I3C_MERRWARN_TIMEOUT) {
dev_dbg(master->dev, "Warning condition: MSTATUS 0x%08x, MERRWARN 0x%08x\n",
mstatus, merrwarn);
return false;
}
dev_err(master->dev,
"Error condition: MSTATUS 0x%08x, MERRWARN 0x%08x\n",
mstatus, merrwarn);
return true;
}
return false;
}
static void svc_i3c_master_enable_interrupts(struct svc_i3c_master *master, u32 mask)
{
writel(mask, master->regs + SVC_I3C_MINTSET);
}
static void svc_i3c_master_disable_interrupts(struct svc_i3c_master *master)
{
u32 mask = readl(master->regs + SVC_I3C_MINTSET);
writel(mask, master->regs + SVC_I3C_MINTCLR);
}
static void svc_i3c_master_clear_merrwarn(struct svc_i3c_master *master)
{
/* Clear pending warnings */
writel(readl(master->regs + SVC_I3C_MERRWARN),
master->regs + SVC_I3C_MERRWARN);
}
static void svc_i3c_master_flush_fifo(struct svc_i3c_master *master)
{
/* Flush FIFOs */
writel(SVC_I3C_MDATACTRL_FLUSHTB | SVC_I3C_MDATACTRL_FLUSHRB,
master->regs + SVC_I3C_MDATACTRL);
}
static void svc_i3c_master_reset_fifo_trigger(struct svc_i3c_master *master)
{
u32 reg;
/* Set RX and TX tigger levels, flush FIFOs */
reg = SVC_I3C_MDATACTRL_FLUSHTB |
SVC_I3C_MDATACTRL_FLUSHRB |
SVC_I3C_MDATACTRL_UNLOCK_TRIG |
SVC_I3C_MDATACTRL_TXTRIG_FIFO_NOT_FULL |
SVC_I3C_MDATACTRL_RXTRIG_FIFO_NOT_EMPTY;
writel(reg, master->regs + SVC_I3C_MDATACTRL);
}
static void svc_i3c_master_reset(struct svc_i3c_master *master)
{
svc_i3c_master_clear_merrwarn(master);
svc_i3c_master_reset_fifo_trigger(master);
svc_i3c_master_disable_interrupts(master);
}
static inline struct svc_i3c_master *
to_svc_i3c_master(struct i3c_master_controller *master)
{
return container_of(master, struct svc_i3c_master, base);
}
static void svc_i3c_master_hj_work(struct work_struct *work)
{
struct svc_i3c_master *master;
master = container_of(work, struct svc_i3c_master, hj_work);
i3c_master_do_daa(&master->base);
}
static struct i3c_dev_desc *
svc_i3c_master_dev_from_addr(struct svc_i3c_master *master,
unsigned int ibiaddr)
{
int i;
for (i = 0; i < SVC_I3C_MAX_DEVS; i++)
if (master->addrs[i] == ibiaddr)
break;
if (i == SVC_I3C_MAX_DEVS)
return NULL;
return master->descs[i];
}
static void svc_i3c_master_emit_stop(struct svc_i3c_master *master)
{
writel(SVC_I3C_MCTRL_REQUEST_STOP, master->regs + SVC_I3C_MCTRL);
/*
* This delay is necessary after the emission of a stop, otherwise eg.
* repeating IBIs do not get detected. There is a note in the manual
* about it, stating that the stop condition might not be settled
* correctly if a start condition follows too rapidly.
*/
udelay(1);
}
static int svc_i3c_master_handle_ibi(struct svc_i3c_master *master,
struct i3c_dev_desc *dev)
{
struct svc_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
struct i3c_ibi_slot *slot;
unsigned int count;
u32 mdatactrl;
int ret, val;
u8 *buf;
slot = i3c_generic_ibi_get_free_slot(data->ibi_pool);
if (!slot)
return -ENOSPC;
slot->len = 0;
buf = slot->data;
ret = readl_relaxed_poll_timeout(master->regs + SVC_I3C_MSTATUS, val,
SVC_I3C_MSTATUS_COMPLETE(val), 0, 1000);
if (ret) {
dev_err(master->dev, "Timeout when polling for COMPLETE\n");
return ret;
}
while (SVC_I3C_MSTATUS_RXPEND(readl(master->regs + SVC_I3C_MSTATUS)) &&
slot->len < SVC_I3C_FIFO_SIZE) {
mdatactrl = readl(master->regs + SVC_I3C_MDATACTRL);
count = SVC_I3C_MDATACTRL_RXCOUNT(mdatactrl);
readsl(master->regs + SVC_I3C_MRDATAB, buf, count);
slot->len += count;
buf += count;
}
master->ibi.tbq_slot = slot;
return 0;
}
static int svc_i3c_master_ack_ibi(struct svc_i3c_master *master,
bool mandatory_byte)
{
unsigned int ibi_ack_nack;
u32 reg;
ibi_ack_nack = SVC_I3C_MCTRL_REQUEST_IBI_ACKNACK;
if (mandatory_byte)
ibi_ack_nack |= SVC_I3C_MCTRL_IBIRESP_ACK_WITH_BYTE;
else
ibi_ack_nack |= SVC_I3C_MCTRL_IBIRESP_ACK_WITHOUT_BYTE;
writel(ibi_ack_nack, master->regs + SVC_I3C_MCTRL);
return readl_poll_timeout_atomic(master->regs + SVC_I3C_MSTATUS, reg,
SVC_I3C_MSTATUS_MCTRLDONE(reg), 1, 1000);
}
static int svc_i3c_master_nack_ibi(struct svc_i3c_master *master)
{
int ret;
u32 reg;
writel(SVC_I3C_MCTRL_REQUEST_IBI_ACKNACK |
SVC_I3C_MCTRL_IBIRESP_NACK,
master->regs + SVC_I3C_MCTRL);
ret = readl_poll_timeout_atomic(master->regs + SVC_I3C_MSTATUS, reg,
SVC_I3C_MSTATUS_MCTRLDONE(reg), 1, 1000);
return ret;
}
static int svc_i3c_master_handle_ibi_won(struct svc_i3c_master *master, u32 mstatus)
{
u32 ibitype;
int ret = 0;
ibitype = SVC_I3C_MSTATUS_IBITYPE(mstatus);
writel(SVC_I3C_MINT_IBIWON, master->regs + SVC_I3C_MSTATUS);
/* Hardware can't auto emit NACK for hot join and master request */
switch (ibitype) {
case SVC_I3C_MSTATUS_IBITYPE_HOT_JOIN:
case SVC_I3C_MSTATUS_IBITYPE_MASTER_REQUEST:
ret = svc_i3c_master_nack_ibi(master);
}
return ret;
}
static void svc_i3c_master_ibi_work(struct work_struct *work)
{
struct svc_i3c_master *master = container_of(work, struct svc_i3c_master, ibi_work);
struct svc_i3c_i2c_dev_data *data;
unsigned int ibitype, ibiaddr;
struct i3c_dev_desc *dev;
u32 status, val;
int ret;
/*
* According to I3C spec ver 1.1, 09-Jun-2021, section 5.1.2.5:
*
* The I3C Controller shall hold SCL low while the Bus is in ACK/NACK Phase of I3C/I2C
* transfer. But maximum stall time is 100us. The IRQs have to be disabled to prevent
* schedule during the whole I3C transaction, otherwise, the I3C bus timeout may happen if
* any irq or schedule happen during transaction.
*/
guard(spinlock_irqsave)(&master->xferqueue.lock);
/*
* IBIWON may be set before SVC_I3C_MCTRL_REQUEST_AUTO_IBI, causing
* readl_relaxed_poll_timeout() to return immediately. Consequently,
* ibitype will be 0 since it was last updated only after the 8th SCL
* cycle, leading to missed client IBI handlers.
*
* A typical scenario is when IBIWON occurs and bus arbitration is lost
* at svc_i3c_master_priv_xfers().
*
* Clear SVC_I3C_MINT_IBIWON before sending SVC_I3C_MCTRL_REQUEST_AUTO_IBI.
*/
writel(SVC_I3C_MINT_IBIWON, master->regs + SVC_I3C_MSTATUS);
/* Acknowledge the incoming interrupt with the AUTOIBI mechanism */
writel(SVC_I3C_MCTRL_REQUEST_AUTO_IBI |
SVC_I3C_MCTRL_IBIRESP_AUTO,
master->regs + SVC_I3C_MCTRL);
/* Wait for IBIWON, should take approximately 100us */
ret = readl_relaxed_poll_timeout_atomic(master->regs + SVC_I3C_MSTATUS, val,
SVC_I3C_MSTATUS_IBIWON(val), 0, 100);
if (ret) {
dev_err(master->dev, "Timeout when polling for IBIWON\n");
svc_i3c_master_emit_stop(master);
goto reenable_ibis;
}
status = readl(master->regs + SVC_I3C_MSTATUS);
ibitype = SVC_I3C_MSTATUS_IBITYPE(status);
ibiaddr = SVC_I3C_MSTATUS_IBIADDR(status);
/* Handle the critical responses to IBI's */
switch (ibitype) {
case SVC_I3C_MSTATUS_IBITYPE_IBI:
dev = svc_i3c_master_dev_from_addr(master, ibiaddr);
if (!dev || !is_events_enabled(master, SVC_I3C_EVENT_IBI))
svc_i3c_master_nack_ibi(master);
else
svc_i3c_master_handle_ibi(master, dev);
break;
case SVC_I3C_MSTATUS_IBITYPE_HOT_JOIN:
if (is_events_enabled(master, SVC_I3C_EVENT_HOTJOIN))
svc_i3c_master_ack_ibi(master, false);
else
svc_i3c_master_nack_ibi(master);
break;
case SVC_I3C_MSTATUS_IBITYPE_MASTER_REQUEST:
svc_i3c_master_nack_ibi(master);
break;
default:
break;
}
/*
* If an error happened, we probably got interrupted and the exchange
* timedout. In this case we just drop everything, emit a stop and wait
* for the slave to interrupt again.
*/
if (svc_i3c_master_error(master)) {
if (master->ibi.tbq_slot) {
data = i3c_dev_get_master_data(dev);
i3c_generic_ibi_recycle_slot(data->ibi_pool,
master->ibi.tbq_slot);
master->ibi.tbq_slot = NULL;
}
svc_i3c_master_emit_stop(master);
goto reenable_ibis;
}
/* Handle the non critical tasks */
switch (ibitype) {
case SVC_I3C_MSTATUS_IBITYPE_IBI:
if (dev) {
i3c_master_queue_ibi(dev, master->ibi.tbq_slot);
master->ibi.tbq_slot = NULL;
}
svc_i3c_master_emit_stop(master);
break;
case SVC_I3C_MSTATUS_IBITYPE_HOT_JOIN:
svc_i3c_master_emit_stop(master);
if (is_events_enabled(master, SVC_I3C_EVENT_HOTJOIN))
queue_work(master->base.wq, &master->hj_work);
break;
case SVC_I3C_MSTATUS_IBITYPE_MASTER_REQUEST:
default:
break;
}
reenable_ibis:
svc_i3c_master_enable_interrupts(master, SVC_I3C_MINT_SLVSTART);
}
static irqreturn_t svc_i3c_master_irq_handler(int irq, void *dev_id)
{
struct svc_i3c_master *master = (struct svc_i3c_master *)dev_id;
u32 active = readl(master->regs + SVC_I3C_MSTATUS);
if (!SVC_I3C_MSTATUS_SLVSTART(active))
return IRQ_NONE;
/* Clear the interrupt status */
writel(SVC_I3C_MINT_SLVSTART, master->regs + SVC_I3C_MSTATUS);
svc_i3c_master_disable_interrupts(master);
/* Handle the interrupt in a non atomic context */
queue_work(master->base.wq, &master->ibi_work);
return IRQ_HANDLED;
}
static int svc_i3c_master_set_speed(struct i3c_master_controller *m,
enum i3c_open_drain_speed speed)
{
struct svc_i3c_master *master = to_svc_i3c_master(m);
struct i3c_bus *bus = i3c_master_get_bus(&master->base);
u32 ppbaud, odbaud, odhpp, mconfig;
unsigned long fclk_rate;
int ret;
ret = pm_runtime_resume_and_get(master->dev);
if (ret < 0) {
dev_err(master->dev, "<%s> Cannot get runtime PM.\n", __func__);
return ret;
}
switch (speed) {
case I3C_OPEN_DRAIN_SLOW_SPEED:
fclk_rate = clk_get_rate(master->fclk);
if (!fclk_rate) {
ret = -EINVAL;
goto rpm_out;
}
/*
* Set 50% duty-cycle I2C speed to I3C OPEN-DRAIN mode, so the first
* broadcast address is visible to all I2C/I3C devices on the I3C bus.
* I3C device working as a I2C device will turn off its 50ns Spike
* Filter to change to I3C mode.
*/
mconfig = master->mctrl_config;
ppbaud = FIELD_GET(GENMASK(11, 8), mconfig);
odhpp = 0;
odbaud = DIV_ROUND_UP(fclk_rate, bus->scl_rate.i2c * (2 + 2 * ppbaud)) - 1;
mconfig &= ~GENMASK(24, 16);
mconfig |= SVC_I3C_MCONFIG_ODBAUD(odbaud) | SVC_I3C_MCONFIG_ODHPP(odhpp);
writel(mconfig, master->regs + SVC_I3C_MCONFIG);
break;
case I3C_OPEN_DRAIN_NORMAL_SPEED:
writel(master->mctrl_config, master->regs + SVC_I3C_MCONFIG);
break;
}
rpm_out:
pm_runtime_mark_last_busy(master->dev);
pm_runtime_put_autosuspend(master->dev);
return ret;
}
static int svc_i3c_master_bus_init(struct i3c_master_controller *m)
{
struct svc_i3c_master *master = to_svc_i3c_master(m);
struct i3c_bus *bus = i3c_master_get_bus(m);
struct i3c_device_info info = {};
unsigned long fclk_rate, fclk_period_ns;
unsigned long i2c_period_ns, i2c_scl_rate, i3c_scl_rate;
unsigned int high_period_ns, od_low_period_ns;
u32 ppbaud, pplow, odhpp, odbaud, odstop, i2cbaud, reg;
int ret;
ret = pm_runtime_resume_and_get(master->dev);
if (ret < 0) {
dev_err(master->dev,
"<%s> cannot resume i3c bus master, err: %d\n",
__func__, ret);
return ret;
}
/* Timings derivation */
fclk_rate = clk_get_rate(master->fclk);
if (!fclk_rate) {
ret = -EINVAL;
goto rpm_out;
}
fclk_period_ns = DIV_ROUND_UP(1000000000, fclk_rate);
i2c_period_ns = DIV_ROUND_UP(1000000000, bus->scl_rate.i2c);
i2c_scl_rate = bus->scl_rate.i2c;
i3c_scl_rate = bus->scl_rate.i3c;
/*
* Using I3C Push-Pull mode, target is 12.5MHz/80ns period.
* Simplest configuration is using a 50% duty-cycle of 40ns.
*/
ppbaud = DIV_ROUND_UP(fclk_rate / 2, i3c_scl_rate) - 1;
pplow = 0;
/*
* Using I3C Open-Drain mode, target is 4.17MHz/240ns with a
* duty-cycle tuned so that high levels are filetered out by
* the 50ns filter (target being 40ns).
*/
odhpp = 1;
high_period_ns = (ppbaud + 1) * fclk_period_ns;
odbaud = DIV_ROUND_UP(fclk_rate, SVC_I3C_QUICK_I2C_CLK * (1 + ppbaud)) - 2;
od_low_period_ns = (odbaud + 1) * high_period_ns;
switch (bus->mode) {
case I3C_BUS_MODE_PURE:
i2cbaud = 0;
odstop = 0;
break;
case I3C_BUS_MODE_MIXED_FAST:
/*
* Using I2C Fm+ mode, target is 1MHz/1000ns, the difference
* between the high and low period does not really matter.
*/
i2cbaud = DIV_ROUND_UP(i2c_period_ns, od_low_period_ns) - 2;
odstop = 1;
break;
case I3C_BUS_MODE_MIXED_LIMITED:
case I3C_BUS_MODE_MIXED_SLOW:
/* I3C PP + I3C OP + I2C OP both use i2c clk rate */
if (ppbaud > SVC_I3C_PPBAUD_MAX) {
ppbaud = SVC_I3C_PPBAUD_MAX;
pplow = DIV_ROUND_UP(fclk_rate, i3c_scl_rate) - (2 + 2 * ppbaud);
}
high_period_ns = (ppbaud + 1) * fclk_period_ns;
odhpp = 0;
odbaud = DIV_ROUND_UP(fclk_rate, i2c_scl_rate * (2 + 2 * ppbaud)) - 1;
od_low_period_ns = (odbaud + 1) * high_period_ns;
i2cbaud = DIV_ROUND_UP(i2c_period_ns, od_low_period_ns) - 2;
odstop = 1;
break;
default:
goto rpm_out;
}
reg = SVC_I3C_MCONFIG_MASTER_EN |
SVC_I3C_MCONFIG_DISTO(0) |
SVC_I3C_MCONFIG_HKEEP(0) |
SVC_I3C_MCONFIG_ODSTOP(odstop) |
SVC_I3C_MCONFIG_PPBAUD(ppbaud) |
SVC_I3C_MCONFIG_PPLOW(pplow) |
SVC_I3C_MCONFIG_ODBAUD(odbaud) |
SVC_I3C_MCONFIG_ODHPP(odhpp) |
SVC_I3C_MCONFIG_SKEW(0) |
SVC_I3C_MCONFIG_I2CBAUD(i2cbaud);
writel(reg, master->regs + SVC_I3C_MCONFIG);
master->mctrl_config = reg;
/* Master core's registration */
ret = i3c_master_get_free_addr(m, 0);
if (ret < 0)
goto rpm_out;
info.dyn_addr = ret;
writel(SVC_MDYNADDR_VALID | SVC_MDYNADDR_ADDR(info.dyn_addr),
master->regs + SVC_I3C_MDYNADDR);
ret = i3c_master_set_info(&master->base, &info);
if (ret)
goto rpm_out;
rpm_out:
pm_runtime_mark_last_busy(master->dev);
pm_runtime_put_autosuspend(master->dev);
return ret;
}
static void svc_i3c_master_bus_cleanup(struct i3c_master_controller *m)
{
struct svc_i3c_master *master = to_svc_i3c_master(m);
int ret;
ret = pm_runtime_resume_and_get(master->dev);
if (ret < 0) {
dev_err(master->dev, "<%s> Cannot get runtime PM.\n", __func__);
return;
}
svc_i3c_master_disable_interrupts(master);
/* Disable master */
writel(0, master->regs + SVC_I3C_MCONFIG);
pm_runtime_mark_last_busy(master->dev);
pm_runtime_put_autosuspend(master->dev);
}
static int svc_i3c_master_reserve_slot(struct svc_i3c_master *master)
{
unsigned int slot;
if (!(master->free_slots & GENMASK(SVC_I3C_MAX_DEVS - 1, 0)))
return -ENOSPC;
slot = ffs(master->free_slots) - 1;
master->free_slots &= ~BIT(slot);
return slot;
}
static void svc_i3c_master_release_slot(struct svc_i3c_master *master,
unsigned int slot)
{
master->free_slots |= BIT(slot);
}
static int svc_i3c_master_attach_i3c_dev(struct i3c_dev_desc *dev)
{
struct i3c_master_controller *m = i3c_dev_get_master(dev);
struct svc_i3c_master *master = to_svc_i3c_master(m);
struct svc_i3c_i2c_dev_data *data;
int slot;
slot = svc_i3c_master_reserve_slot(master);
if (slot < 0)
return slot;
data = kzalloc(sizeof(*data), GFP_KERNEL);
if (!data) {
svc_i3c_master_release_slot(master, slot);
return -ENOMEM;
}
data->ibi = -1;
data->index = slot;
master->addrs[slot] = dev->info.dyn_addr ? dev->info.dyn_addr :
dev->info.static_addr;
master->descs[slot] = dev;
i3c_dev_set_master_data(dev, data);
return 0;
}
static int svc_i3c_master_reattach_i3c_dev(struct i3c_dev_desc *dev,
u8 old_dyn_addr)
{
struct i3c_master_controller *m = i3c_dev_get_master(dev);
struct svc_i3c_master *master = to_svc_i3c_master(m);
struct svc_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
master->addrs[data->index] = dev->info.dyn_addr ? dev->info.dyn_addr :
dev->info.static_addr;
return 0;
}
static void svc_i3c_master_detach_i3c_dev(struct i3c_dev_desc *dev)
{
struct svc_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
struct i3c_master_controller *m = i3c_dev_get_master(dev);
struct svc_i3c_master *master = to_svc_i3c_master(m);
master->addrs[data->index] = 0;
svc_i3c_master_release_slot(master, data->index);
kfree(data);
}
static int svc_i3c_master_attach_i2c_dev(struct i2c_dev_desc *dev)
{
struct i3c_master_controller *m = i2c_dev_get_master(dev);
struct svc_i3c_master *master = to_svc_i3c_master(m);
struct svc_i3c_i2c_dev_data *data;
int slot;
slot = svc_i3c_master_reserve_slot(master);
if (slot < 0)
return slot;
data = kzalloc(sizeof(*data), GFP_KERNEL);
if (!data) {
svc_i3c_master_release_slot(master, slot);
return -ENOMEM;
}
data->index = slot;
master->addrs[slot] = dev->addr;
i2c_dev_set_master_data(dev, data);
return 0;
}
static void svc_i3c_master_detach_i2c_dev(struct i2c_dev_desc *dev)
{
struct svc_i3c_i2c_dev_data *data = i2c_dev_get_master_data(dev);
struct i3c_master_controller *m = i2c_dev_get_master(dev);
struct svc_i3c_master *master = to_svc_i3c_master(m);
svc_i3c_master_release_slot(master, data->index);
kfree(data);
}
static int svc_i3c_master_readb(struct svc_i3c_master *master, u8 *dst,
unsigned int len)
{
int ret, i;
u32 reg;
for (i = 0; i < len; i++) {
ret = readl_poll_timeout_atomic(master->regs + SVC_I3C_MSTATUS,
reg,
SVC_I3C_MSTATUS_RXPEND(reg),
0, 1000);
if (ret)
return ret;
dst[i] = readl(master->regs + SVC_I3C_MRDATAB);
}
return 0;
}
static int svc_i3c_master_do_daa_locked(struct svc_i3c_master *master,
u8 *addrs, unsigned int *count)
{
u64 prov_id[SVC_I3C_MAX_DEVS] = {}, nacking_prov_id = 0;
unsigned int dev_nb = 0, last_addr = 0;
u32 reg;
int ret, i;
while (true) {
/* clean SVC_I3C_MINT_IBIWON w1c bits */
writel(SVC_I3C_MINT_IBIWON, master->regs + SVC_I3C_MSTATUS);
/* SVC_I3C_MCTRL_REQUEST_PROC_DAA have two mode, ENTER DAA or PROCESS DAA.
*
* ENTER DAA:
* 1 will issue START, 7E, ENTDAA, and then emits 7E/R to process first target.
* 2 Stops just before the new Dynamic Address (DA) is to be emitted.
*
* PROCESS DAA:
* 1 The DA is written using MWDATAB or ADDR bits 6:0.
* 2 ProcessDAA is requested again to write the new address, and then starts the
* next (START, 7E, ENTDAA) unless marked to STOP; an MSTATUS indicating NACK
* means DA was not accepted (e.g. parity error). If PROCESSDAA is NACKed on the
* 7E/R, which means no more Slaves need a DA, then a COMPLETE will be signaled
* (along with DONE), and a STOP issued automatically.
*/
writel(SVC_I3C_MCTRL_REQUEST_PROC_DAA |
SVC_I3C_MCTRL_TYPE_I3C |
SVC_I3C_MCTRL_IBIRESP_NACK |
SVC_I3C_MCTRL_DIR(SVC_I3C_MCTRL_DIR_WRITE),
master->regs + SVC_I3C_MCTRL);
/*
* Either one slave will send its ID, or the assignment process
* is done.
*/
ret = readl_poll_timeout_atomic(master->regs + SVC_I3C_MSTATUS,
reg,
SVC_I3C_MSTATUS_RXPEND(reg) |
SVC_I3C_MSTATUS_MCTRLDONE(reg),
1, 1000);
if (ret)
break;
if (SVC_I3C_MSTATUS_RXPEND(reg)) {
u8 data[6];
/*
* We only care about the 48-bit provisioned ID yet to
* be sure a device does not nack an address twice.
* Otherwise, we would just need to flush the RX FIFO.
*/
ret = svc_i3c_master_readb(master, data, 6);
if (ret)
break;
for (i = 0; i < 6; i++)
prov_id[dev_nb] |= (u64)(data[i]) << (8 * (5 - i));
/* We do not care about the BCR and DCR yet */
ret = svc_i3c_master_readb(master, data, 2);
if (ret)
break;
} else if (SVC_I3C_MSTATUS_IBIWON(reg)) {
ret = svc_i3c_master_handle_ibi_won(master, reg);
if (ret)
break;
continue;
} else if (SVC_I3C_MSTATUS_MCTRLDONE(reg)) {
if (SVC_I3C_MSTATUS_STATE_IDLE(reg) &&
SVC_I3C_MSTATUS_COMPLETE(reg)) {
/*
* All devices received and acked they dynamic
* address, this is the natural end of the DAA
* procedure.
*
* Hardware will auto emit STOP at this case.
*/
*count = dev_nb;
return 0;
} else if (SVC_I3C_MSTATUS_NACKED(reg)) {
/* No I3C devices attached */
if (dev_nb == 0) {
/*
* Hardware can't treat first NACK for ENTAA as normal
* COMPLETE. So need manual emit STOP.
*/
ret = 0;
*count = 0;
break;
}
/*
* A slave device nacked the address, this is
* allowed only once, DAA will be stopped and
* then resumed. The same device is supposed to
* answer again immediately and shall ack the
* address this time.
*/
if (prov_id[dev_nb] == nacking_prov_id) {
ret = -EIO;
break;
}
dev_nb--;
nacking_prov_id = prov_id[dev_nb];
svc_i3c_master_emit_stop(master);
continue;
} else {
break;
}
}
/* Wait for the slave to be ready to receive its address */
ret = readl_poll_timeout_atomic(master->regs + SVC_I3C_MSTATUS,
reg,
SVC_I3C_MSTATUS_MCTRLDONE(reg) &&
SVC_I3C_MSTATUS_STATE_DAA(reg) &&
SVC_I3C_MSTATUS_BETWEEN(reg),
0, 1000);
if (ret)
break;
/* Give the slave device a suitable dynamic address */
ret = i3c_master_get_free_addr(&master->base, last_addr + 1);
if (ret < 0)
break;
addrs[dev_nb] = ret;
dev_dbg(master->dev, "DAA: device %d assigned to 0x%02x\n",
dev_nb, addrs[dev_nb]);
writel(addrs[dev_nb], master->regs + SVC_I3C_MWDATAB);
last_addr = addrs[dev_nb++];
}
/* Need manual issue STOP except for Complete condition */
svc_i3c_master_emit_stop(master);
return ret;
}
static int svc_i3c_update_ibirules(struct svc_i3c_master *master)
{
struct i3c_dev_desc *dev;
u32 reg_mbyte = 0, reg_nobyte = SVC_I3C_IBIRULES_NOBYTE;
unsigned int mbyte_addr_ok = 0, mbyte_addr_ko = 0, nobyte_addr_ok = 0,
nobyte_addr_ko = 0;
bool list_mbyte = false, list_nobyte = false;
/* Create the IBIRULES register for both cases */
i3c_bus_for_each_i3cdev(&master->base.bus, dev) {
if (I3C_BCR_DEVICE_ROLE(dev->info.bcr) == I3C_BCR_I3C_MASTER)
continue;
if (dev->info.bcr & I3C_BCR_IBI_PAYLOAD) {
reg_mbyte |= SVC_I3C_IBIRULES_ADDR(mbyte_addr_ok,
dev->info.dyn_addr);
/* IBI rules cannot be applied to devices with MSb=1 */
if (dev->info.dyn_addr & BIT(7))
mbyte_addr_ko++;
else
mbyte_addr_ok++;
} else {
reg_nobyte |= SVC_I3C_IBIRULES_ADDR(nobyte_addr_ok,
dev->info.dyn_addr);
/* IBI rules cannot be applied to devices with MSb=1 */
if (dev->info.dyn_addr & BIT(7))
nobyte_addr_ko++;
else
nobyte_addr_ok++;
}
}
/* Device list cannot be handled by hardware */
if (!mbyte_addr_ko && mbyte_addr_ok <= SVC_I3C_IBIRULES_ADDRS)
list_mbyte = true;
if (!nobyte_addr_ko && nobyte_addr_ok <= SVC_I3C_IBIRULES_ADDRS)
list_nobyte = true;
/* No list can be properly handled, return an error */
if (!list_mbyte && !list_nobyte)
return -ERANGE;
/* Pick the first list that can be handled by hardware, randomly */
if (list_mbyte)
writel(reg_mbyte, master->regs + SVC_I3C_IBIRULES);
else
writel(reg_nobyte, master->regs + SVC_I3C_IBIRULES);
return 0;
}
static int svc_i3c_master_do_daa(struct i3c_master_controller *m)
{
struct svc_i3c_master *master = to_svc_i3c_master(m);
u8 addrs[SVC_I3C_MAX_DEVS];
unsigned long flags;
unsigned int dev_nb;
int ret, i;
ret = pm_runtime_resume_and_get(master->dev);
if (ret < 0) {
dev_err(master->dev, "<%s> Cannot get runtime PM.\n", __func__);
return ret;
}
spin_lock_irqsave(&master->xferqueue.lock, flags);
ret = svc_i3c_master_do_daa_locked(master, addrs, &dev_nb);
spin_unlock_irqrestore(&master->xferqueue.lock, flags);
svc_i3c_master_clear_merrwarn(master);
if (ret)
goto rpm_out;
/*
* Register all devices who participated to the core
*
* If two devices (A and B) are detected in DAA and address 0xa is assigned to
* device A and 0xb to device B, a failure in i3c_master_add_i3c_dev_locked()
* for device A (addr: 0xa) could prevent device B (addr: 0xb) from being
* registered on the bus. The I3C stack might still consider 0xb a free
* address. If a subsequent Hotjoin occurs, 0xb might be assigned to Device A,
* causing both devices A and B to use the same address 0xb, violating the I3C
* specification.
*
* The return value for i3c_master_add_i3c_dev_locked() should not be checked
* because subsequent steps will scan the entire I3C bus, independent of
* whether i3c_master_add_i3c_dev_locked() returns success.
*
* If device A registration fails, there is still a chance to register device
* B. i3c_master_add_i3c_dev_locked() can reset DAA if a failure occurs while
* retrieving device information.
*/
for (i = 0; i < dev_nb; i++)
i3c_master_add_i3c_dev_locked(m, addrs[i]);
/* Configure IBI auto-rules */
ret = svc_i3c_update_ibirules(master);
if (ret)
dev_err(master->dev, "Cannot handle such a list of devices");
rpm_out:
pm_runtime_mark_last_busy(master->dev);
pm_runtime_put_autosuspend(master->dev);
return ret;
}
static int svc_i3c_master_read(struct svc_i3c_master *master,
u8 *in, unsigned int len)
{
int offset = 0, i;
u32 mdctrl, mstatus;
bool completed = false;
unsigned int count;
unsigned long start = jiffies;
while (!completed) {
mstatus = readl(master->regs + SVC_I3C_MSTATUS);
if (SVC_I3C_MSTATUS_COMPLETE(mstatus) != 0)
completed = true;
if (time_after(jiffies, start + msecs_to_jiffies(1000))) {
dev_dbg(master->dev, "I3C read timeout\n");
return -ETIMEDOUT;
}
mdctrl = readl(master->regs + SVC_I3C_MDATACTRL);
count = SVC_I3C_MDATACTRL_RXCOUNT(mdctrl);
if (offset + count > len) {
dev_err(master->dev, "I3C receive length too long!\n");
return -EINVAL;
}
for (i = 0; i < count; i++)
in[offset + i] = readl(master->regs + SVC_I3C_MRDATAB);
offset += count;
}
return offset;
}
static int svc_i3c_master_write(struct svc_i3c_master *master,
const u8 *out, unsigned int len)
{
int offset = 0, ret;
u32 mdctrl;
while (offset < len) {
ret = readl_poll_timeout(master->regs + SVC_I3C_MDATACTRL,
mdctrl,
!(mdctrl & SVC_I3C_MDATACTRL_TXFULL),
0, 1000);
if (ret)
return ret;
/*
* The last byte to be sent over the bus must either have the
* "end" bit set or be written in MWDATABE.
*/
if (likely(offset < (len - 1)))
writel(out[offset++], master->regs + SVC_I3C_MWDATAB);
else
writel(out[offset++], master->regs + SVC_I3C_MWDATABE);
}
return 0;
}
static int svc_i3c_master_xfer(struct svc_i3c_master *master,
bool rnw, unsigned int xfer_type, u8 addr,
u8 *in, const u8 *out, unsigned int xfer_len,
unsigned int *actual_len, bool continued)
{
int retry = 2;
u32 reg;
int ret;
/* clean SVC_I3C_MINT_IBIWON w1c bits */
writel(SVC_I3C_MINT_IBIWON, master->regs + SVC_I3C_MSTATUS);
while (retry--) {
writel(SVC_I3C_MCTRL_REQUEST_START_ADDR |
xfer_type |
SVC_I3C_MCTRL_IBIRESP_NACK |
SVC_I3C_MCTRL_DIR(rnw) |
SVC_I3C_MCTRL_ADDR(addr) |
SVC_I3C_MCTRL_RDTERM(*actual_len),
master->regs + SVC_I3C_MCTRL);
ret = readl_poll_timeout(master->regs + SVC_I3C_MSTATUS, reg,
SVC_I3C_MSTATUS_MCTRLDONE(reg), 0, 1000);
if (ret)
goto emit_stop;
/*
* According to I3C spec ver 1.1.1, 5.1.2.2.3 Consequence of Controller Starting a
* Frame with I3C Target Address.
*
* The I3C Controller normally should start a Frame, the Address may be arbitrated,
* and so the Controller shall monitor to see whether an In-Band Interrupt request,
* a Controller Role Request (i.e., Secondary Controller requests to become the
* Active Controller), or a Hot-Join Request has been made.
*
* If missed IBIWON check, the wrong data will be return. When IBIWON happen, issue
* repeat start. Address arbitrate only happen at START, never happen at REPEAT
* start.
*/
if (SVC_I3C_MSTATUS_IBIWON(reg)) {
ret = svc_i3c_master_handle_ibi_won(master, reg);
if (ret)
goto emit_stop;
continue;
}
if (readl(master->regs + SVC_I3C_MERRWARN) & SVC_I3C_MERRWARN_NACK) {
/*
* According to I3C Spec 1.1.1, 11-Jun-2021, section: 5.1.2.2.3.
* If the Controller chooses to start an I3C Message with an I3C Dynamic
* Address, then special provisions shall be made because that same I3C
* Target may be initiating an IBI or a Controller Role Request. So, one of
* three things may happen: (skip 1, 2)
*
* 3. The Addresses match and the RnW bits also match, and so neither
* Controller nor Target will ACK since both are expecting the other side to
* provide ACK. As a result, each side might think it had "won" arbitration,
* but neither side would continue, as each would subsequently see that the
* other did not provide ACK.
* ...
* For either value of RnW: Due to the NACK, the Controller shall defer the
* Private Write or Private Read, and should typically transmit the Target
* Address again after a Repeated START (i.e., the next one or any one prior
* to a STOP in the Frame). Since the Address Header following a Repeated
* START is not arbitrated, the Controller will always win (see Section
* 5.1.2.2.4).
*/
if (retry && addr != 0x7e) {
writel(SVC_I3C_MERRWARN_NACK, master->regs + SVC_I3C_MERRWARN);
} else {
ret = -ENXIO;
*actual_len = 0;
goto emit_stop;
}
} else {
break;
}
}
if (rnw)
ret = svc_i3c_master_read(master, in, xfer_len);
else
ret = svc_i3c_master_write(master, out, xfer_len);
if (ret < 0)
goto emit_stop;
if (rnw)
*actual_len = ret;
ret = readl_poll_timeout(master->regs + SVC_I3C_MSTATUS, reg,
SVC_I3C_MSTATUS_COMPLETE(reg), 0, 1000);
if (ret)
goto emit_stop;
writel(SVC_I3C_MINT_COMPLETE, master->regs + SVC_I3C_MSTATUS);
if (!continued) {
svc_i3c_master_emit_stop(master);
/* Wait idle if stop is sent. */
readl_poll_timeout(master->regs + SVC_I3C_MSTATUS, reg,
SVC_I3C_MSTATUS_STATE_IDLE(reg), 0, 1000);
}
return 0;
emit_stop:
svc_i3c_master_emit_stop(master);
svc_i3c_master_clear_merrwarn(master);
return ret;
}
static struct svc_i3c_xfer *
svc_i3c_master_alloc_xfer(struct svc_i3c_master *master, unsigned int ncmds)
{
struct svc_i3c_xfer *xfer;
xfer = kzalloc(struct_size(xfer, cmds, ncmds), GFP_KERNEL);
if (!xfer)
return NULL;
INIT_LIST_HEAD(&xfer->node);
xfer->ncmds = ncmds;
xfer->ret = -ETIMEDOUT;
return xfer;
}
static void svc_i3c_master_free_xfer(struct svc_i3c_xfer *xfer)
{
kfree(xfer);
}
static void svc_i3c_master_dequeue_xfer_locked(struct svc_i3c_master *master,
struct svc_i3c_xfer *xfer)
{
if (master->xferqueue.cur == xfer)
master->xferqueue.cur = NULL;
else
list_del_init(&xfer->node);
}
static void svc_i3c_master_dequeue_xfer(struct svc_i3c_master *master,
struct svc_i3c_xfer *xfer)
{
unsigned long flags;
spin_lock_irqsave(&master->xferqueue.lock, flags);
svc_i3c_master_dequeue_xfer_locked(master, xfer);
spin_unlock_irqrestore(&master->xferqueue.lock, flags);
}
static void svc_i3c_master_start_xfer_locked(struct svc_i3c_master *master)
{
struct svc_i3c_xfer *xfer = master->xferqueue.cur;
int ret, i;
if (!xfer)
return;
svc_i3c_master_clear_merrwarn(master);
svc_i3c_master_flush_fifo(master);
for (i = 0; i < xfer->ncmds; i++) {
struct svc_i3c_cmd *cmd = &xfer->cmds[i];
ret = svc_i3c_master_xfer(master, cmd->rnw, xfer->type,
cmd->addr, cmd->in, cmd->out,
cmd->len, &cmd->actual_len,
cmd->continued);
/* cmd->xfer is NULL if I2C or CCC transfer */
if (cmd->xfer)
cmd->xfer->actual_len = cmd->actual_len;
if (ret)
break;
}
xfer->ret = ret;
complete(&xfer->comp);
if (ret < 0)
svc_i3c_master_dequeue_xfer_locked(master, xfer);
xfer = list_first_entry_or_null(&master->xferqueue.list,
struct svc_i3c_xfer,
node);
if (xfer)
list_del_init(&xfer->node);
master->xferqueue.cur = xfer;
svc_i3c_master_start_xfer_locked(master);
}
static void svc_i3c_master_enqueue_xfer(struct svc_i3c_master *master,
struct svc_i3c_xfer *xfer)
{
unsigned long flags;
int ret;
ret = pm_runtime_resume_and_get(master->dev);
if (ret < 0) {
dev_err(master->dev, "<%s> Cannot get runtime PM.\n", __func__);
return;
}
init_completion(&xfer->comp);
spin_lock_irqsave(&master->xferqueue.lock, flags);
if (master->xferqueue.cur) {
list_add_tail(&xfer->node, &master->xferqueue.list);
} else {
master->xferqueue.cur = xfer;
svc_i3c_master_start_xfer_locked(master);
}
spin_unlock_irqrestore(&master->xferqueue.lock, flags);
pm_runtime_mark_last_busy(master->dev);
pm_runtime_put_autosuspend(master->dev);
}
static bool
svc_i3c_master_supports_ccc_cmd(struct i3c_master_controller *master,
const struct i3c_ccc_cmd *cmd)
{
/* No software support for CCC commands targeting more than one slave */
return (cmd->ndests == 1);
}
static int svc_i3c_master_send_bdcast_ccc_cmd(struct svc_i3c_master *master,
struct i3c_ccc_cmd *ccc)
{
unsigned int xfer_len = ccc->dests[0].payload.len + 1;
struct svc_i3c_xfer *xfer;
struct svc_i3c_cmd *cmd;
u8 *buf;
int ret;
xfer = svc_i3c_master_alloc_xfer(master, 1);
if (!xfer)
return -ENOMEM;
buf = kmalloc(xfer_len, GFP_KERNEL);
if (!buf) {
svc_i3c_master_free_xfer(xfer);
return -ENOMEM;
}
buf[0] = ccc->id;
memcpy(&buf[1], ccc->dests[0].payload.data, ccc->dests[0].payload.len);
xfer->type = SVC_I3C_MCTRL_TYPE_I3C;
cmd = &xfer->cmds[0];
cmd->addr = ccc->dests[0].addr;
cmd->rnw = ccc->rnw;
cmd->in = NULL;
cmd->out = buf;
cmd->len = xfer_len;
cmd->actual_len = 0;
cmd->continued = false;
mutex_lock(&master->lock);
svc_i3c_master_enqueue_xfer(master, xfer);
if (!wait_for_completion_timeout(&xfer->comp, msecs_to_jiffies(1000)))
svc_i3c_master_dequeue_xfer(master, xfer);
mutex_unlock(&master->lock);
ret = xfer->ret;
kfree(buf);
svc_i3c_master_free_xfer(xfer);
return ret;
}
static int svc_i3c_master_send_direct_ccc_cmd(struct svc_i3c_master *master,
struct i3c_ccc_cmd *ccc)
{
unsigned int xfer_len = ccc->dests[0].payload.len;
unsigned int actual_len = ccc->rnw ? xfer_len : 0;
struct svc_i3c_xfer *xfer;
struct svc_i3c_cmd *cmd;
int ret;
xfer = svc_i3c_master_alloc_xfer(master, 2);
if (!xfer)
return -ENOMEM;
xfer->type = SVC_I3C_MCTRL_TYPE_I3C;
/* Broadcasted message */
cmd = &xfer->cmds[0];
cmd->addr = I3C_BROADCAST_ADDR;
cmd->rnw = 0;
cmd->in = NULL;
cmd->out = &ccc->id;
cmd->len = 1;
cmd->actual_len = 0;
cmd->continued = true;
/* Directed message */
cmd = &xfer->cmds[1];
cmd->addr = ccc->dests[0].addr;
cmd->rnw = ccc->rnw;
cmd->in = ccc->rnw ? ccc->dests[0].payload.data : NULL;
cmd->out = ccc->rnw ? NULL : ccc->dests[0].payload.data;
cmd->len = xfer_len;
cmd->actual_len = actual_len;
cmd->continued = false;
mutex_lock(&master->lock);
svc_i3c_master_enqueue_xfer(master, xfer);
if (!wait_for_completion_timeout(&xfer->comp, msecs_to_jiffies(1000)))
svc_i3c_master_dequeue_xfer(master, xfer);
mutex_unlock(&master->lock);
if (cmd->actual_len != xfer_len)
ccc->dests[0].payload.len = cmd->actual_len;
ret = xfer->ret;
svc_i3c_master_free_xfer(xfer);
return ret;
}
static int svc_i3c_master_send_ccc_cmd(struct i3c_master_controller *m,
struct i3c_ccc_cmd *cmd)
{
struct svc_i3c_master *master = to_svc_i3c_master(m);
bool broadcast = cmd->id < 0x80;
int ret;
if (broadcast)
ret = svc_i3c_master_send_bdcast_ccc_cmd(master, cmd);
else
ret = svc_i3c_master_send_direct_ccc_cmd(master, cmd);
if (ret)
cmd->err = I3C_ERROR_M2;
return ret;
}
static int svc_i3c_master_priv_xfers(struct i3c_dev_desc *dev,
struct i3c_priv_xfer *xfers,
int nxfers)
{
struct i3c_master_controller *m = i3c_dev_get_master(dev);
struct svc_i3c_master *master = to_svc_i3c_master(m);
struct svc_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
struct svc_i3c_xfer *xfer;
int ret, i;
xfer = svc_i3c_master_alloc_xfer(master, nxfers);
if (!xfer)
return -ENOMEM;
xfer->type = SVC_I3C_MCTRL_TYPE_I3C;
for (i = 0; i < nxfers; i++) {
struct svc_i3c_cmd *cmd = &xfer->cmds[i];
cmd->xfer = &xfers[i];
cmd->addr = master->addrs[data->index];
cmd->rnw = xfers[i].rnw;
cmd->in = xfers[i].rnw ? xfers[i].data.in : NULL;
cmd->out = xfers[i].rnw ? NULL : xfers[i].data.out;
cmd->len = xfers[i].len;
cmd->actual_len = xfers[i].rnw ? xfers[i].len : 0;
cmd->continued = (i + 1) < nxfers;
}
mutex_lock(&master->lock);
svc_i3c_master_enqueue_xfer(master, xfer);
if (!wait_for_completion_timeout(&xfer->comp, msecs_to_jiffies(1000)))
svc_i3c_master_dequeue_xfer(master, xfer);
mutex_unlock(&master->lock);
ret = xfer->ret;
svc_i3c_master_free_xfer(xfer);
return ret;
}
static int svc_i3c_master_i2c_xfers(struct i2c_dev_desc *dev,
const struct i2c_msg *xfers,
int nxfers)
{
struct i3c_master_controller *m = i2c_dev_get_master(dev);
struct svc_i3c_master *master = to_svc_i3c_master(m);
struct svc_i3c_i2c_dev_data *data = i2c_dev_get_master_data(dev);
struct svc_i3c_xfer *xfer;
int ret, i;
xfer = svc_i3c_master_alloc_xfer(master, nxfers);
if (!xfer)
return -ENOMEM;
xfer->type = SVC_I3C_MCTRL_TYPE_I2C;
for (i = 0; i < nxfers; i++) {
struct svc_i3c_cmd *cmd = &xfer->cmds[i];
cmd->addr = master->addrs[data->index];
cmd->rnw = xfers[i].flags & I2C_M_RD;
cmd->in = cmd->rnw ? xfers[i].buf : NULL;
cmd->out = cmd->rnw ? NULL : xfers[i].buf;
cmd->len = xfers[i].len;
cmd->actual_len = cmd->rnw ? xfers[i].len : 0;
cmd->continued = (i + 1 < nxfers);
}
mutex_lock(&master->lock);
svc_i3c_master_enqueue_xfer(master, xfer);
if (!wait_for_completion_timeout(&xfer->comp, msecs_to_jiffies(1000)))
svc_i3c_master_dequeue_xfer(master, xfer);
mutex_unlock(&master->lock);
ret = xfer->ret;
svc_i3c_master_free_xfer(xfer);
return ret;
}
static int svc_i3c_master_request_ibi(struct i3c_dev_desc *dev,
const struct i3c_ibi_setup *req)
{
struct i3c_master_controller *m = i3c_dev_get_master(dev);
struct svc_i3c_master *master = to_svc_i3c_master(m);
struct svc_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
unsigned long flags;
unsigned int i;
if (dev->ibi->max_payload_len > SVC_I3C_FIFO_SIZE) {
dev_err(master->dev, "IBI max payload %d should be < %d\n",
dev->ibi->max_payload_len, SVC_I3C_FIFO_SIZE);
return -ERANGE;
}
data->ibi_pool = i3c_generic_ibi_alloc_pool(dev, req);
if (IS_ERR(data->ibi_pool))
return PTR_ERR(data->ibi_pool);
spin_lock_irqsave(&master->ibi.lock, flags);
for (i = 0; i < master->ibi.num_slots; i++) {
if (!master->ibi.slots[i]) {
data->ibi = i;
master->ibi.slots[i] = dev;
break;
}
}
spin_unlock_irqrestore(&master->ibi.lock, flags);
if (i < master->ibi.num_slots)
return 0;
i3c_generic_ibi_free_pool(data->ibi_pool);
data->ibi_pool = NULL;
return -ENOSPC;
}
static void svc_i3c_master_free_ibi(struct i3c_dev_desc *dev)
{
struct i3c_master_controller *m = i3c_dev_get_master(dev);
struct svc_i3c_master *master = to_svc_i3c_master(m);
struct svc_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
unsigned long flags;
spin_lock_irqsave(&master->ibi.lock, flags);
master->ibi.slots[data->ibi] = NULL;
data->ibi = -1;
spin_unlock_irqrestore(&master->ibi.lock, flags);
i3c_generic_ibi_free_pool(data->ibi_pool);
}
static int svc_i3c_master_enable_ibi(struct i3c_dev_desc *dev)
{
struct i3c_master_controller *m = i3c_dev_get_master(dev);
struct svc_i3c_master *master = to_svc_i3c_master(m);
int ret;
ret = pm_runtime_resume_and_get(master->dev);
if (ret < 0) {
dev_err(master->dev, "<%s> Cannot get runtime PM.\n", __func__);
return ret;
}
master->enabled_events |= SVC_I3C_EVENT_IBI;
svc_i3c_master_enable_interrupts(master, SVC_I3C_MINT_SLVSTART);
return i3c_master_enec_locked(m, dev->info.dyn_addr, I3C_CCC_EVENT_SIR);
}
static int svc_i3c_master_disable_ibi(struct i3c_dev_desc *dev)
{
struct i3c_master_controller *m = i3c_dev_get_master(dev);
struct svc_i3c_master *master = to_svc_i3c_master(m);
int ret;
master->enabled_events &= ~SVC_I3C_EVENT_IBI;
if (!master->enabled_events)
svc_i3c_master_disable_interrupts(master);
ret = i3c_master_disec_locked(m, dev->info.dyn_addr, I3C_CCC_EVENT_SIR);
pm_runtime_mark_last_busy(master->dev);
pm_runtime_put_autosuspend(master->dev);
return ret;
}
static int svc_i3c_master_enable_hotjoin(struct i3c_master_controller *m)
{
struct svc_i3c_master *master = to_svc_i3c_master(m);
int ret;
ret = pm_runtime_resume_and_get(master->dev);
if (ret < 0) {
dev_err(master->dev, "<%s> Cannot get runtime PM.\n", __func__);
return ret;
}
master->enabled_events |= SVC_I3C_EVENT_HOTJOIN;
svc_i3c_master_enable_interrupts(master, SVC_I3C_MINT_SLVSTART);
return 0;
}
static int svc_i3c_master_disable_hotjoin(struct i3c_master_controller *m)
{
struct svc_i3c_master *master = to_svc_i3c_master(m);
master->enabled_events &= ~SVC_I3C_EVENT_HOTJOIN;
if (!master->enabled_events)
svc_i3c_master_disable_interrupts(master);
pm_runtime_mark_last_busy(master->dev);
pm_runtime_put_autosuspend(master->dev);
return 0;
}
static void svc_i3c_master_recycle_ibi_slot(struct i3c_dev_desc *dev,
struct i3c_ibi_slot *slot)
{
struct svc_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
i3c_generic_ibi_recycle_slot(data->ibi_pool, slot);
}
static const struct i3c_master_controller_ops svc_i3c_master_ops = {
.bus_init = svc_i3c_master_bus_init,
.bus_cleanup = svc_i3c_master_bus_cleanup,
.attach_i3c_dev = svc_i3c_master_attach_i3c_dev,
.detach_i3c_dev = svc_i3c_master_detach_i3c_dev,
.reattach_i3c_dev = svc_i3c_master_reattach_i3c_dev,
.attach_i2c_dev = svc_i3c_master_attach_i2c_dev,
.detach_i2c_dev = svc_i3c_master_detach_i2c_dev,
.do_daa = svc_i3c_master_do_daa,
.supports_ccc_cmd = svc_i3c_master_supports_ccc_cmd,
.send_ccc_cmd = svc_i3c_master_send_ccc_cmd,
.priv_xfers = svc_i3c_master_priv_xfers,
.i2c_xfers = svc_i3c_master_i2c_xfers,
.request_ibi = svc_i3c_master_request_ibi,
.free_ibi = svc_i3c_master_free_ibi,
.recycle_ibi_slot = svc_i3c_master_recycle_ibi_slot,
.enable_ibi = svc_i3c_master_enable_ibi,
.disable_ibi = svc_i3c_master_disable_ibi,
.enable_hotjoin = svc_i3c_master_enable_hotjoin,
.disable_hotjoin = svc_i3c_master_disable_hotjoin,
.set_speed = svc_i3c_master_set_speed,
};
static int svc_i3c_master_prepare_clks(struct svc_i3c_master *master)
{
int ret = 0;
ret = clk_prepare_enable(master->pclk);
if (ret)
return ret;
ret = clk_prepare_enable(master->fclk);
if (ret) {
clk_disable_unprepare(master->pclk);
return ret;
}
ret = clk_prepare_enable(master->sclk);
if (ret) {
clk_disable_unprepare(master->pclk);
clk_disable_unprepare(master->fclk);
return ret;
}
return 0;
}
static void svc_i3c_master_unprepare_clks(struct svc_i3c_master *master)
{
clk_disable_unprepare(master->pclk);
clk_disable_unprepare(master->fclk);
clk_disable_unprepare(master->sclk);
}
static int svc_i3c_master_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct svc_i3c_master *master;
int ret;
master = devm_kzalloc(dev, sizeof(*master), GFP_KERNEL);
if (!master)
return -ENOMEM;
master->regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(master->regs))
return PTR_ERR(master->regs);
master->pclk = devm_clk_get(dev, "pclk");
if (IS_ERR(master->pclk))
return PTR_ERR(master->pclk);
master->fclk = devm_clk_get(dev, "fast_clk");
if (IS_ERR(master->fclk))
return PTR_ERR(master->fclk);
master->sclk = devm_clk_get(dev, "slow_clk");
if (IS_ERR(master->sclk))
return PTR_ERR(master->sclk);
master->irq = platform_get_irq(pdev, 0);
if (master->irq < 0)
return master->irq;
master->dev = dev;
ret = svc_i3c_master_prepare_clks(master);
if (ret)
return ret;
INIT_WORK(&master->hj_work, svc_i3c_master_hj_work);
INIT_WORK(&master->ibi_work, svc_i3c_master_ibi_work);
mutex_init(&master->lock);
ret = devm_request_irq(dev, master->irq, svc_i3c_master_irq_handler,
IRQF_NO_SUSPEND, "svc-i3c-irq", master);
if (ret)
goto err_disable_clks;
master->free_slots = GENMASK(SVC_I3C_MAX_DEVS - 1, 0);
spin_lock_init(&master->xferqueue.lock);
INIT_LIST_HEAD(&master->xferqueue.list);
spin_lock_init(&master->ibi.lock);
master->ibi.num_slots = SVC_I3C_MAX_DEVS;
master->ibi.slots = devm_kcalloc(&pdev->dev, master->ibi.num_slots,
sizeof(*master->ibi.slots),
GFP_KERNEL);
if (!master->ibi.slots) {
ret = -ENOMEM;
goto err_disable_clks;
}
platform_set_drvdata(pdev, master);
pm_runtime_set_autosuspend_delay(&pdev->dev, SVC_I3C_PM_TIMEOUT_MS);
pm_runtime_use_autosuspend(&pdev->dev);
pm_runtime_get_noresume(&pdev->dev);
pm_runtime_set_active(&pdev->dev);
pm_runtime_enable(&pdev->dev);
svc_i3c_master_reset(master);
/* Register the master */
ret = i3c_master_register(&master->base, &pdev->dev,
&svc_i3c_master_ops, false);
if (ret)
goto rpm_disable;
pm_runtime_mark_last_busy(&pdev->dev);
pm_runtime_put_autosuspend(&pdev->dev);
return 0;
rpm_disable:
pm_runtime_dont_use_autosuspend(&pdev->dev);
pm_runtime_put_noidle(&pdev->dev);
pm_runtime_set_suspended(&pdev->dev);
pm_runtime_disable(&pdev->dev);
err_disable_clks:
svc_i3c_master_unprepare_clks(master);
return ret;
}
static void svc_i3c_master_remove(struct platform_device *pdev)
{
struct svc_i3c_master *master = platform_get_drvdata(pdev);
cancel_work_sync(&master->hj_work);
i3c_master_unregister(&master->base);
pm_runtime_dont_use_autosuspend(&pdev->dev);
pm_runtime_disable(&pdev->dev);
}
static void svc_i3c_save_regs(struct svc_i3c_master *master)
{
master->saved_regs.mconfig = readl(master->regs + SVC_I3C_MCONFIG);
master->saved_regs.mdynaddr = readl(master->regs + SVC_I3C_MDYNADDR);
}
static void svc_i3c_restore_regs(struct svc_i3c_master *master)
{
if (readl(master->regs + SVC_I3C_MDYNADDR) !=
master->saved_regs.mdynaddr) {
writel(master->saved_regs.mconfig,
master->regs + SVC_I3C_MCONFIG);
writel(master->saved_regs.mdynaddr,
master->regs + SVC_I3C_MDYNADDR);
}
}
static int __maybe_unused svc_i3c_runtime_suspend(struct device *dev)
{
struct svc_i3c_master *master = dev_get_drvdata(dev);
svc_i3c_save_regs(master);
svc_i3c_master_unprepare_clks(master);
pinctrl_pm_select_sleep_state(dev);
return 0;
}
static int __maybe_unused svc_i3c_runtime_resume(struct device *dev)
{
struct svc_i3c_master *master = dev_get_drvdata(dev);
pinctrl_pm_select_default_state(dev);
svc_i3c_master_prepare_clks(master);
svc_i3c_restore_regs(master);
return 0;
}
static const struct dev_pm_ops svc_i3c_pm_ops = {
SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
pm_runtime_force_resume)
SET_RUNTIME_PM_OPS(svc_i3c_runtime_suspend,
svc_i3c_runtime_resume, NULL)
};
static const struct of_device_id svc_i3c_master_of_match_tbl[] = {
{ .compatible = "silvaco,i3c-master-v1"},
{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, svc_i3c_master_of_match_tbl);
static struct platform_driver svc_i3c_master = {
.probe = svc_i3c_master_probe,
.remove_new = svc_i3c_master_remove,
.driver = {
.name = "silvaco-i3c-master",
.of_match_table = svc_i3c_master_of_match_tbl,
.pm = &svc_i3c_pm_ops,
},
};
module_platform_driver(svc_i3c_master);
MODULE_AUTHOR("Conor Culhane <conor.culhane@silvaco.com>");
MODULE_AUTHOR("Miquel Raynal <miquel.raynal@bootlin.com>");
MODULE_DESCRIPTION("Silvaco dual-role I3C master driver");
MODULE_LICENSE("GPL v2");
