i3c: dw: Add support for in-band interrupts

This change adds support for receiving and dequeueing i3c IBIs.

By setting struct dw_i3c_master->ibi_capable before probe, a platform
implementation can select the IBI-enabled version of the i3c_master_ops,
enabling the global IBI infrastrcture for that controller.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Link: https://lore.kernel.org/r/79daeefd7ccb7c935d0c159149df21a6c9a73ffa.1680161823.git.jk@codeconstruct.com.au
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
This commit is contained in:
Jeremy Kerr 2023-03-30 15:50:34 +08:00 коммит произвёл Alexandre Belloni
Родитель e2d43101f6
Коммит e389b1d72a
2 изменённых файлов: 289 добавлений и 3 удалений

Просмотреть файл

@ -76,7 +76,22 @@
#define RX_TX_DATA_PORT 0x14
#define IBI_QUEUE_STATUS 0x18
#define IBI_QUEUE_STATUS_IBI_ID(x) (((x) & GENMASK(15, 8)) >> 8)
#define IBI_QUEUE_STATUS_DATA_LEN(x) ((x) & GENMASK(7, 0))
#define IBI_QUEUE_IBI_ADDR(x) (IBI_QUEUE_STATUS_IBI_ID(x) >> 1)
#define IBI_QUEUE_IBI_RNW(x) (IBI_QUEUE_STATUS_IBI_ID(x) & BIT(0))
#define IBI_TYPE_MR(x) \
((IBI_QUEUE_IBI_ADDR(x) != I3C_HOT_JOIN_ADDR) && !IBI_QUEUE_IBI_RNW(x))
#define IBI_TYPE_HJ(x) \
((IBI_QUEUE_IBI_ADDR(x) == I3C_HOT_JOIN_ADDR) && !IBI_QUEUE_IBI_RNW(x))
#define IBI_TYPE_SIRQ(x) \
((IBI_QUEUE_IBI_ADDR(x) != I3C_HOT_JOIN_ADDR) && IBI_QUEUE_IBI_RNW(x))
#define QUEUE_THLD_CTRL 0x1c
#define QUEUE_THLD_CTRL_IBI_STAT_MASK GENMASK(31, 24)
#define QUEUE_THLD_CTRL_IBI_STAT(x) (((x) - 1) << 24)
#define QUEUE_THLD_CTRL_IBI_DATA_MASK GENMASK(20, 16)
#define QUEUE_THLD_CTRL_IBI_DATA(x) ((x) << 16)
#define QUEUE_THLD_CTRL_RESP_BUF_MASK GENMASK(15, 8)
#define QUEUE_THLD_CTRL_RESP_BUF(x) (((x) - 1) << 8)
@ -186,6 +201,8 @@
#define EXTENDED_CAPABILITY 0xe8
#define SLAVE_CONFIG 0xec
#define DEV_ADDR_TABLE_IBI_MDB BIT(12)
#define DEV_ADDR_TABLE_SIR_REJECT BIT(13)
#define DEV_ADDR_TABLE_LEGACY_I2C_DEV BIT(31)
#define DEV_ADDR_TABLE_DYNAMIC_ADDR(x) (((x) << 16) & GENMASK(23, 16))
#define DEV_ADDR_TABLE_STATIC_ADDR(x) ((x) & GENMASK(6, 0))
@ -221,6 +238,7 @@ struct dw_i3c_xfer {
struct dw_i3c_i2c_dev_data {
u8 index;
struct i3c_generic_ibi_pool *ibi_pool;
};
static u8 even_parity(u8 p)
@ -336,6 +354,12 @@ static void dw_i3c_master_read_rx_fifo(struct dw_i3c_master *master,
return dw_i3c_master_read_fifo(master, RX_TX_DATA_PORT, bytes, nbytes);
}
static void dw_i3c_master_read_ibi_fifo(struct dw_i3c_master *master,
u8 *bytes, int nbytes)
{
return dw_i3c_master_read_fifo(master, IBI_QUEUE_STATUS, bytes, nbytes);
}
static struct dw_i3c_xfer *
dw_i3c_master_alloc_xfer(struct dw_i3c_master *master, unsigned int ncmds)
{
@ -605,7 +629,11 @@ static int dw_i3c_master_bus_init(struct i3c_master_controller *m)
}
thld_ctrl = readl(master->regs + QUEUE_THLD_CTRL);
thld_ctrl &= ~QUEUE_THLD_CTRL_RESP_BUF_MASK;
thld_ctrl &= ~(QUEUE_THLD_CTRL_RESP_BUF_MASK |
QUEUE_THLD_CTRL_IBI_STAT_MASK |
QUEUE_THLD_CTRL_IBI_STAT_MASK);
thld_ctrl |= QUEUE_THLD_CTRL_IBI_STAT(1) |
QUEUE_THLD_CTRL_IBI_DATA(31);
writel(thld_ctrl, master->regs + QUEUE_THLD_CTRL);
thld_ctrl = readl(master->regs + DATA_BUFFER_THLD_CTRL);
@ -1074,6 +1102,226 @@ static void dw_i3c_master_detach_i2c_dev(struct i2c_dev_desc *dev)
kfree(data);
}
static int dw_i3c_master_request_ibi(struct i3c_dev_desc *dev,
const struct i3c_ibi_setup *req)
{
struct dw_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
struct i3c_master_controller *m = i3c_dev_get_master(dev);
struct dw_i3c_master *master = to_dw_i3c_master(m);
unsigned long flags;
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->devs_lock, flags);
master->devs[data->index].ibi_dev = dev;
spin_unlock_irqrestore(&master->devs_lock, flags);
return 0;
}
static void dw_i3c_master_free_ibi(struct i3c_dev_desc *dev)
{
struct dw_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
struct i3c_master_controller *m = i3c_dev_get_master(dev);
struct dw_i3c_master *master = to_dw_i3c_master(m);
unsigned long flags;
spin_lock_irqsave(&master->devs_lock, flags);
master->devs[data->index].ibi_dev = NULL;
spin_unlock_irqrestore(&master->devs_lock, flags);
i3c_generic_ibi_free_pool(data->ibi_pool);
data->ibi_pool = NULL;
}
static void dw_i3c_master_set_sir_enabled(struct dw_i3c_master *master,
struct i3c_dev_desc *dev,
u8 idx, bool enable)
{
unsigned long flags;
u32 dat_entry, reg;
bool global;
dat_entry = DEV_ADDR_TABLE_LOC(master->datstartaddr, idx);
spin_lock_irqsave(&master->devs_lock, flags);
reg = readl(master->regs + dat_entry);
if (enable) {
reg &= ~DEV_ADDR_TABLE_SIR_REJECT;
if (dev->info.bcr & I3C_BCR_IBI_PAYLOAD)
reg |= DEV_ADDR_TABLE_IBI_MDB;
} else {
reg |= DEV_ADDR_TABLE_SIR_REJECT;
}
writel(reg, master->regs + dat_entry);
reg = readl(master->regs + IBI_SIR_REQ_REJECT);
if (enable) {
global = reg == 0xffffffff;
reg &= ~BIT(idx);
} else {
global = reg == 0;
reg |= BIT(idx);
}
writel(reg, master->regs + IBI_SIR_REQ_REJECT);
if (global) {
reg = readl(master->regs + INTR_STATUS_EN);
reg &= ~INTR_IBI_THLD_STAT;
if (enable)
reg |= INTR_IBI_THLD_STAT;
writel(reg, master->regs + INTR_STATUS_EN);
reg = readl(master->regs + INTR_SIGNAL_EN);
reg &= ~INTR_IBI_THLD_STAT;
if (enable)
reg |= INTR_IBI_THLD_STAT;
writel(reg, master->regs + INTR_SIGNAL_EN);
}
spin_unlock_irqrestore(&master->devs_lock, flags);
}
static int dw_i3c_master_enable_ibi(struct i3c_dev_desc *dev)
{
struct dw_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
struct i3c_master_controller *m = i3c_dev_get_master(dev);
struct dw_i3c_master *master = to_dw_i3c_master(m);
int rc;
dw_i3c_master_set_sir_enabled(master, dev, data->index, true);
rc = i3c_master_enec_locked(m, dev->info.dyn_addr, I3C_CCC_EVENT_SIR);
if (rc)
dw_i3c_master_set_sir_enabled(master, dev, data->index, false);
return rc;
}
static int dw_i3c_master_disable_ibi(struct i3c_dev_desc *dev)
{
struct dw_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
struct i3c_master_controller *m = i3c_dev_get_master(dev);
struct dw_i3c_master *master = to_dw_i3c_master(m);
int rc;
rc = i3c_master_disec_locked(m, dev->info.dyn_addr, I3C_CCC_EVENT_SIR);
if (rc)
return rc;
dw_i3c_master_set_sir_enabled(master, dev, data->index, false);
return 0;
}
static void dw_i3c_master_recycle_ibi_slot(struct i3c_dev_desc *dev,
struct i3c_ibi_slot *slot)
{
struct dw_i3c_i2c_dev_data *data = i3c_dev_get_master_data(dev);
i3c_generic_ibi_recycle_slot(data->ibi_pool, slot);
}
static void dw_i3c_master_drain_ibi_queue(struct dw_i3c_master *master,
int len)
{
int i;
for (i = 0; i < DIV_ROUND_UP(len, 4); i++)
readl(master->regs + IBI_QUEUE_STATUS);
}
static void dw_i3c_master_handle_ibi_sir(struct dw_i3c_master *master,
u32 status)
{
struct dw_i3c_i2c_dev_data *data;
struct i3c_ibi_slot *slot;
struct i3c_dev_desc *dev;
unsigned long flags;
u8 addr, len;
int idx;
addr = IBI_QUEUE_IBI_ADDR(status);
len = IBI_QUEUE_STATUS_DATA_LEN(status);
spin_lock_irqsave(&master->devs_lock, flags);
idx = dw_i3c_master_get_addr_pos(master, addr);
if (idx < 0) {
dev_dbg_ratelimited(&master->base.dev,
"IBI from unknown addr 0x%x\n", addr);
goto err_drain;
}
dev = master->devs[idx].ibi_dev;
if (!dev || !dev->ibi) {
dev_dbg_ratelimited(&master->base.dev,
"IBI from non-requested dev idx %d\n", idx);
goto err_drain;
}
data = i3c_dev_get_master_data(dev);
slot = i3c_generic_ibi_get_free_slot(data->ibi_pool);
if (!slot) {
dev_dbg_ratelimited(&master->base.dev,
"No IBI slots available\n");
goto err_drain;
}
if (dev->ibi->max_payload_len < len) {
dev_dbg_ratelimited(&master->base.dev,
"IBI payload len %d greater than max %d\n",
len, dev->ibi->max_payload_len);
goto err_drain;
}
if (len) {
dw_i3c_master_read_ibi_fifo(master, slot->data, len);
slot->len = len;
}
i3c_master_queue_ibi(dev, slot);
spin_unlock_irqrestore(&master->devs_lock, flags);
return;
err_drain:
dw_i3c_master_drain_ibi_queue(master, len);
spin_unlock_irqrestore(&master->devs_lock, flags);
}
/* "ibis": referring to In-Band Interrupts, and not
* https://en.wikipedia.org/wiki/Australian_white_ibis. The latter should
* not be handled.
*/
static void dw_i3c_master_irq_handle_ibis(struct dw_i3c_master *master)
{
unsigned int i, len, n_ibis;
u32 reg;
reg = readl(master->regs + QUEUE_STATUS_LEVEL);
n_ibis = QUEUE_STATUS_IBI_STATUS_CNT(reg);
if (!n_ibis)
return;
for (i = 0; i < n_ibis; i++) {
reg = readl(master->regs + IBI_QUEUE_STATUS);
if (IBI_TYPE_SIRQ(reg)) {
dw_i3c_master_handle_ibi_sir(master, reg);
} else {
len = IBI_QUEUE_STATUS_DATA_LEN(reg);
dev_info(&master->base.dev,
"unsupported IBI type 0x%lx len %d\n",
IBI_QUEUE_STATUS_IBI_ID(reg), len);
dw_i3c_master_drain_ibi_queue(master, len);
}
}
}
static irqreturn_t dw_i3c_master_irq_handler(int irq, void *dev_id)
{
struct dw_i3c_master *master = dev_id;
@ -1092,6 +1340,9 @@ static irqreturn_t dw_i3c_master_irq_handler(int irq, void *dev_id)
writel(INTR_TRANSFER_ERR_STAT, master->regs + INTR_STATUS);
spin_unlock(&master->xferqueue.lock);
if (status & INTR_IBI_THLD_STAT)
dw_i3c_master_irq_handle_ibis(master);
return IRQ_HANDLED;
}
@ -1110,6 +1361,26 @@ static const struct i3c_master_controller_ops dw_mipi_i3c_ops = {
.i2c_xfers = dw_i3c_master_i2c_xfers,
};
static const struct i3c_master_controller_ops dw_mipi_i3c_ibi_ops = {
.bus_init = dw_i3c_master_bus_init,
.bus_cleanup = dw_i3c_master_bus_cleanup,
.attach_i3c_dev = dw_i3c_master_attach_i3c_dev,
.reattach_i3c_dev = dw_i3c_master_reattach_i3c_dev,
.detach_i3c_dev = dw_i3c_master_detach_i3c_dev,
.do_daa = dw_i3c_master_daa,
.supports_ccc_cmd = dw_i3c_master_supports_ccc_cmd,
.send_ccc_cmd = dw_i3c_master_send_ccc_cmd,
.priv_xfers = dw_i3c_master_priv_xfers,
.attach_i2c_dev = dw_i3c_master_attach_i2c_dev,
.detach_i2c_dev = dw_i3c_master_detach_i2c_dev,
.i2c_xfers = dw_i3c_master_i2c_xfers,
.request_ibi = dw_i3c_master_request_ibi,
.free_ibi = dw_i3c_master_free_ibi,
.enable_ibi = dw_i3c_master_enable_ibi,
.disable_ibi = dw_i3c_master_disable_ibi,
.recycle_ibi_slot = dw_i3c_master_recycle_ibi_slot,
};
/* default platform ops implementations */
static int dw_i3c_platform_init_nop(struct dw_i3c_master *i3c)
{
@ -1123,6 +1394,7 @@ static const struct dw_i3c_platform_ops dw_i3c_platform_ops_default = {
int dw_i3c_common_probe(struct dw_i3c_master *master,
struct platform_device *pdev)
{
const struct i3c_master_controller_ops *ops;
int ret, irq;
if (!master->platform_ops)
@ -1172,8 +1444,11 @@ int dw_i3c_common_probe(struct dw_i3c_master *master,
master->maxdevs = ret >> 16;
master->free_pos = GENMASK(master->maxdevs - 1, 0);
ret = i3c_master_register(&master->base, &pdev->dev,
&dw_mipi_i3c_ops, false);
ops = &dw_mipi_i3c_ops;
if (master->ibi_capable)
ops = &dw_mipi_i3c_ibi_ops;
ret = i3c_master_register(&master->base, &pdev->dev, ops, false);
if (ret)
goto err_assert_rst;

Просмотреть файл

@ -19,6 +19,7 @@ struct dw_i3c_master_caps {
struct dw_i3c_dat_entry {
u8 addr;
struct i3c_dev_desc *ibi_dev;
};
struct dw_i3c_master {
@ -37,12 +38,22 @@ struct dw_i3c_master {
struct clk *core_clk;
char version[5];
char type[5];
bool ibi_capable;
/*
* Per-device hardware data, used to manage the device address table
* (DAT)
*
* Locking: the devs array may be referenced in IRQ context while
* processing an IBI. However, IBIs (for a specific device, which
* implies a specific DAT entry) can only happen while interrupts are
* requested for that device, which is serialised against other
* insertions/removals from the array by the global i3c infrastructure.
* So, devs_lock protects against concurrent updates to devs->ibi_dev
* between request_ibi/free_ibi and the IBI irq event.
*/
struct dw_i3c_dat_entry devs[DW_I3C_MAX_DEVS];
spinlock_t devs_lock;
/* platform-specific data */
const struct dw_i3c_platform_ops *platform_ops;