[PATCH v5 09/10] i2c: npcm: Support NPCM845

Tyrone Ting
2022-05-17T10:13:59Z

From: Tyrone Ting <kfting@nuvoton.com>

Add NPCM8XX I2C support.
The NPCM8XX uses a similar i2c module as NPCM7XX.
The internal HW FIFO is larger in NPCM8XX.

Signed-off-by: Tyrone Ting <kfting@nuvoton.com>
---
drivers/i2c/busses/Kconfig | 8 +--
drivers/i2c/busses/Makefile | 2 +-
drivers/i2c/busses/i2c-npcm7xx.c | 114 +++++++++++++++++++------------
3 files changed, 76 insertions(+), 48 deletions(-)

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index a1bae59208e3..b1d7069dd377 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -838,13 +838,13 @@ config I2C_NOMADIK
I2C interface from ST-Ericsson's Nomadik and Ux500 architectures,
as well as the STA2X11 PCIe I/O HUB.

-config I2C_NPCM7XX
+config I2C_NPCM
tristate "Nuvoton I2C Controller"
- depends on ARCH_NPCM7XX || COMPILE_TEST
+ depends on ARCH_NPCM || COMPILE_TEST
help
If you say yes to this option, support will be included for the
- Nuvoton I2C controller, which is available on the NPCM7xx BMC
- controller.
+ Nuvoton I2C controller, which is available on the NPCM BMC
+ controllers.
Driver can also support slave mode (select I2C_SLAVE).

config I2C_OCORES
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 479f60e4ee3d..b0a10e5d9ee9 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -84,7 +84,7 @@ obj-$(CONFIG_I2C_MT7621) += i2c-mt7621.o
obj-$(CONFIG_I2C_MV64XXX) += i2c-mv64xxx.o
obj-$(CONFIG_I2C_MXS) += i2c-mxs.o
obj-$(CONFIG_I2C_NOMADIK) += i2c-nomadik.o
-obj-$(CONFIG_I2C_NPCM7XX) += i2c-npcm7xx.o
+obj-$(CONFIG_I2C_NPCM) += i2c-npcm7xx.o
obj-$(CONFIG_I2C_OCORES) += i2c-ocores.o
obj-$(CONFIG_I2C_OMAP) += i2c-omap.o
obj-$(CONFIG_I2C_OWL) += i2c-owl.o
diff --git a/drivers/i2c/busses/i2c-npcm7xx.c b/drivers/i2c/busses/i2c-npcm7xx.c
index 3f86895f5e64..a032b407f104 100644
--- a/drivers/i2c/busses/i2c-npcm7xx.c
+++ b/drivers/i2c/busses/i2c-npcm7xx.c
@@ -17,6 +17,7 @@
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of.h>
+#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>

@@ -91,7 +92,6 @@ enum i2c_addr {

/* init register and default value required to enable module */
#define NPCM_I2CSEGCTL 0xE4
-#define NPCM_I2CSEGCTL_INIT_VAL 0x0333F000

/* Common regs */
#define NPCM_I2CSDA 0x00
@@ -228,8 +228,7 @@ static const int npcm_i2caddr[I2C_NUM_OWN_ADDR] = {
#define NPCM_I2CFIF_CTS_CLR_FIFO BIT(6)
#define NPCM_I2CFIF_CTS_SLVRSTR BIT(7)

-/* NPCM_I2CTXF_CTL reg fields */
-#define NPCM_I2CTXF_CTL_TX_THR GENMASK(4, 0)
+/* NPCM_I2CTXF_CTL reg field */
#define NPCM_I2CTXF_CTL_THR_TXIE BIT(6)

/* NPCM_I2CT_OUT reg fields */
@@ -238,22 +237,18 @@ static const int npcm_i2caddr[I2C_NUM_OWN_ADDR] = {
#define NPCM_I2CT_OUT_T_OUTST BIT(7)

/* NPCM_I2CTXF_STS reg fields */
-#define NPCM_I2CTXF_STS_TX_BYTES GENMASK(4, 0)
#define NPCM_I2CTXF_STS_TX_THST BIT(6)

/* NPCM_I2CRXF_STS reg fields */
-#define NPCM_I2CRXF_STS_RX_BYTES GENMASK(4, 0)
#define NPCM_I2CRXF_STS_RX_THST BIT(6)

/* NPCM_I2CFIF_CTL reg fields */
#define NPCM_I2CFIF_CTL_FIFO_EN BIT(4)

/* NPCM_I2CRXF_CTL reg fields */
-#define NPCM_I2CRXF_CTL_RX_THR GENMASK(4, 0)
-#define NPCM_I2CRXF_CTL_LAST_PEC BIT(5)
#define NPCM_I2CRXF_CTL_THR_RXIE BIT(6)

-#define I2C_HW_FIFO_SIZE 16
+#define MAX_I2C_HW_FIFO_SIZE 32

/* I2C_VER reg fields */
#define I2C_VER_VERSION GENMASK(6, 0)
@@ -270,11 +265,36 @@ static const int npcm_i2caddr[I2C_NUM_OWN_ADDR] = {
#define I2C_FREQ_MIN_HZ 10000
#define I2C_FREQ_MAX_HZ I2C_MAX_FAST_MODE_PLUS_FREQ

+struct npcm_i2c_data {
+ u8 fifo_size;
+ u32 segctl_init_val;
+ u8 txf_sts_tx_bytes;
+ u8 rxf_sts_rx_bytes;
+ u8 rxf_ctl_last_pec;
+};
+
+static const struct npcm_i2c_data npxm7xx_i2c_data = {
+ .fifo_size = 16,
+ .segctl_init_val = 0x0333F000,
+ .txf_sts_tx_bytes = GENMASK(4, 0),
+ .rxf_sts_rx_bytes = GENMASK(4, 0),
+ .rxf_ctl_last_pec = BIT(5),
+};
+
+static const struct npcm_i2c_data npxm8xx_i2c_data = {
+ .fifo_size = 32,
+ .segctl_init_val = 0x9333F000,
+ .txf_sts_tx_bytes = GENMASK(5, 0),
+ .rxf_sts_rx_bytes = GENMASK(5, 0),
+ .rxf_ctl_last_pec = BIT(7),
+};
+
/* Status of one I2C module */
struct npcm_i2c {
struct i2c_adapter adap;
struct device *dev;
unsigned char __iomem *reg;
+ const struct npcm_i2c_data *data;
spinlock_t lock; /* IRQ synchronization */
struct completion cmd_complete;
int cmd_err;
@@ -307,8 +327,8 @@ struct npcm_i2c {
int slv_rd_ind;
int slv_wr_size;
int slv_wr_ind;
- u8 slv_rd_buf[I2C_HW_FIFO_SIZE];
- u8 slv_wr_buf[I2C_HW_FIFO_SIZE];
+ u8 slv_rd_buf[MAX_I2C_HW_FIFO_SIZE];
+ u8 slv_wr_buf[MAX_I2C_HW_FIFO_SIZE];
#endif
struct dentry *debugfs; /* debugfs device directory */
u64 ber_cnt;
@@ -441,7 +461,7 @@ static inline bool npcm_i2c_tx_fifo_empty(struct npcm_i2c *bus)

tx_fifo_sts = ioread8(bus->reg + NPCM_I2CTXF_STS);
/* check if TX FIFO is not empty */
- if ((tx_fifo_sts & NPCM_I2CTXF_STS_TX_BYTES) == 0)
+ if ((tx_fifo_sts & bus->data->txf_sts_tx_bytes) == 0)
return false;

/* check if TX FIFO status bit is set: */
@@ -454,7 +474,7 @@ static inline bool npcm_i2c_rx_fifo_full(struct npcm_i2c *bus)

rx_fifo_sts = ioread8(bus->reg + NPCM_I2CRXF_STS);
/* check if RX FIFO is not empty: */
- if ((rx_fifo_sts & NPCM_I2CRXF_STS_RX_BYTES) == 0)
+ if ((rx_fifo_sts & bus->data->rxf_sts_rx_bytes) == 0)
return false;

/* check if rx fifo full status is set: */
@@ -742,11 +762,11 @@ static void npcm_i2c_callback(struct npcm_i2c *bus,
static u8 npcm_i2c_fifo_usage(struct npcm_i2c *bus)
{
if (bus->operation == I2C_WRITE_OPER)
- return FIELD_GET(NPCM_I2CTXF_STS_TX_BYTES,
- ioread8(bus->reg + NPCM_I2CTXF_STS));
+ return (bus->data->txf_sts_tx_bytes &
+ ioread8(bus->reg + NPCM_I2CTXF_STS));
if (bus->operation == I2C_READ_OPER)
- return FIELD_GET(NPCM_I2CRXF_STS_RX_BYTES,
- ioread8(bus->reg + NPCM_I2CRXF_STS));
+ return (bus->data->rxf_sts_rx_bytes &
+ ioread8(bus->reg + NPCM_I2CRXF_STS));
return 0;
}

@@ -758,13 +778,13 @@ static void npcm_i2c_write_to_fifo_master(struct npcm_i2c *bus, u16 max_bytes)
* Fill the FIFO, while the FIFO is not full and there are more bytes
* to write
*/
- size_free_fifo = I2C_HW_FIFO_SIZE - npcm_i2c_fifo_usage(bus);
+ size_free_fifo = bus->data->fifo_size - npcm_i2c_fifo_usage(bus);
while (max_bytes-- && size_free_fifo) {
if (bus->wr_ind < bus->wr_size)
npcm_i2c_wr_byte(bus, bus->wr_buf[bus->wr_ind++]);
else
npcm_i2c_wr_byte(bus, 0xFF);
- size_free_fifo = I2C_HW_FIFO_SIZE - npcm_i2c_fifo_usage(bus);
+ size_free_fifo = bus->data->fifo_size - npcm_i2c_fifo_usage(bus);
}
}

@@ -785,11 +805,11 @@ static void npcm_i2c_set_fifo(struct npcm_i2c *bus, int nread, int nwrite)

/* configure RX FIFO */
if (nread > 0) {
- rxf_ctl = min_t(int, nread, I2C_HW_FIFO_SIZE);
+ rxf_ctl = min_t(int, nread, bus->data->fifo_size);

/* set LAST bit. if LAST is set next FIFO packet is nacked */
- if (nread <= I2C_HW_FIFO_SIZE)
- rxf_ctl |= NPCM_I2CRXF_CTL_LAST_PEC;
+ if (nread <= bus->data->fifo_size)
+ rxf_ctl |= bus->data->rxf_ctl_last_pec;

/*
* if we are about to read the first byte in blk rd mode,
@@ -807,9 +827,9 @@ static void npcm_i2c_set_fifo(struct npcm_i2c *bus, int nread, int nwrite)

/* configure TX FIFO */
if (nwrite > 0) {
- if (nwrite > I2C_HW_FIFO_SIZE)
+ if (nwrite > bus->data->fifo_size)
/* data to send is more then FIFO size. */
- iowrite8(I2C_HW_FIFO_SIZE, bus->reg + NPCM_I2CTXF_CTL);
+ iowrite8(bus->data->fifo_size, bus->reg + NPCM_I2CTXF_CTL);
else
iowrite8(nwrite, bus->reg + NPCM_I2CTXF_CTL);

@@ -876,13 +896,13 @@ static void npcm_i2c_write_fifo_slave(struct npcm_i2c *bus, u16 max_bytes)
npcm_i2c_clear_fifo_int(bus);
npcm_i2c_clear_tx_fifo(bus);
iowrite8(0, bus->reg + NPCM_I2CTXF_CTL);
- while (max_bytes-- && I2C_HW_FIFO_SIZE != npcm_i2c_fifo_usage(bus)) {
+ while (max_bytes-- && bus->data->fifo_size != npcm_i2c_fifo_usage(bus)) {
if (bus->slv_wr_size <= 0)
break;
- bus->slv_wr_ind = bus->slv_wr_ind % I2C_HW_FIFO_SIZE;
+ bus->slv_wr_ind = bus->slv_wr_ind & (bus->data->fifo_size - 1);
npcm_i2c_wr_byte(bus, bus->slv_wr_buf[bus->slv_wr_ind]);
bus->slv_wr_ind++;
- bus->slv_wr_ind = bus->slv_wr_ind % I2C_HW_FIFO_SIZE;
+ bus->slv_wr_ind = bus->slv_wr_ind & (bus->data->fifo_size - 1);
bus->slv_wr_size--;
}
}
@@ -897,7 +917,7 @@ static void npcm_i2c_read_fifo_slave(struct npcm_i2c *bus, u8 bytes_in_fifo)
while (bytes_in_fifo--) {
data = npcm_i2c_rd_byte(bus);

- bus->slv_rd_ind = bus->slv_rd_ind % I2C_HW_FIFO_SIZE;
+ bus->slv_rd_ind = bus->slv_rd_ind & (bus->data->fifo_size - 1);
bus->slv_rd_buf[bus->slv_rd_ind] = data;
bus->slv_rd_ind++;

@@ -915,8 +935,8 @@ static int npcm_i2c_slave_get_wr_buf(struct npcm_i2c *bus)
int ret = bus->slv_wr_ind;

/* fill a cyclic buffer */
- for (i = 0; i < I2C_HW_FIFO_SIZE; i++) {
- if (bus->slv_wr_size >= I2C_HW_FIFO_SIZE)
+ for (i = 0; i < bus->data->fifo_size; i++) {
+ if (bus->slv_wr_size >= bus->data->fifo_size)
break;
if (bus->state == I2C_SLAVE_MATCH) {
i2c_slave_event(bus->slave, I2C_SLAVE_READ_REQUESTED, &value);
@@ -924,11 +944,11 @@ static int npcm_i2c_slave_get_wr_buf(struct npcm_i2c *bus)
} else {
i2c_slave_event(bus->slave, I2C_SLAVE_READ_PROCESSED, &value);
}
- ind = (bus->slv_wr_ind + bus->slv_wr_size) % I2C_HW_FIFO_SIZE;
+ ind = (bus->slv_wr_ind + bus->slv_wr_size) & (bus->data->fifo_size - 1);
bus->slv_wr_buf[ind] = value;
bus->slv_wr_size++;
}
- return I2C_HW_FIFO_SIZE - ret;
+ return bus->data->fifo_size - ret;
}

static void npcm_i2c_slave_send_rd_buf(struct npcm_i2c *bus)
@@ -963,7 +983,7 @@ static void npcm_i2c_slave_receive(struct npcm_i2c *bus, u16 nread,
bus->slv_rd_ind = 0;

iowrite8(0, bus->reg + NPCM_I2CTXF_CTL);
- iowrite8(I2C_HW_FIFO_SIZE, bus->reg + NPCM_I2CRXF_CTL);
+ iowrite8(bus->data->fifo_size, bus->reg + NPCM_I2CRXF_CTL);
npcm_i2c_clear_tx_fifo(bus);
npcm_i2c_clear_rx_fifo(bus);
}
@@ -996,12 +1016,12 @@ static void npcm_i2c_slave_wr_buf_sync(struct npcm_i2c *bus)
{
int left_in_fifo;

- left_in_fifo = FIELD_GET(NPCM_I2CTXF_STS_TX_BYTES,
- ioread8(bus->reg + NPCM_I2CTXF_STS));
+ left_in_fifo = bus->data->txf_sts_tx_bytes &
+ ioread8(bus->reg + NPCM_I2CTXF_STS);

/* fifo already full: */
- if (left_in_fifo >= I2C_HW_FIFO_SIZE ||
- bus->slv_wr_size >= I2C_HW_FIFO_SIZE)
+ if (left_in_fifo >= bus->data->fifo_size ||
+ bus->slv_wr_size >= bus->data->fifo_size)
return;

/* update the wr fifo index back to the untransmitted bytes: */
@@ -1009,7 +1029,7 @@ static void npcm_i2c_slave_wr_buf_sync(struct npcm_i2c *bus)
bus->slv_wr_size = bus->slv_wr_size + left_in_fifo;

if (bus->slv_wr_ind < 0)
- bus->slv_wr_ind += I2C_HW_FIFO_SIZE;
+ bus->slv_wr_ind += bus->data->fifo_size;
}

static void npcm_i2c_slave_rd_wr(struct npcm_i2c *bus)
@@ -1155,7 +1175,7 @@ static irqreturn_t npcm_i2c_int_slave_handler(struct npcm_i2c *bus)
npcm_i2c_clear_rx_fifo(bus);
npcm_i2c_clear_tx_fifo(bus);
iowrite8(0, bus->reg + NPCM_I2CTXF_CTL);
- iowrite8(I2C_HW_FIFO_SIZE, bus->reg + NPCM_I2CRXF_CTL);
+ iowrite8(bus->data->fifo_size, bus->reg + NPCM_I2CRXF_CTL);
if (NPCM_I2CST_XMIT & i2cst) {
bus->operation = I2C_WRITE_OPER;
} else {
@@ -1316,8 +1336,8 @@ static void npcm_i2c_master_fifo_read(struct npcm_i2c *bus)
* read == FIFO Size + C (where C < FIFO Size)then first read C bytes
* and in the next int we read rest of the data.
*/
- if (rcount < (2 * I2C_HW_FIFO_SIZE) && rcount > I2C_HW_FIFO_SIZE)
- fifo_bytes = rcount - I2C_HW_FIFO_SIZE;
+ if (rcount < (2 * bus->data->fifo_size) && rcount > bus->data->fifo_size)
+ fifo_bytes = rcount - bus->data->fifo_size;

if (rcount <= fifo_bytes) {
/* last bytes are about to be read - end of tx */
@@ -2196,7 +2216,7 @@ static int npcm_i2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
* It cannot be cleared without resetting the module.
*/
else if (bus->cmd_err &&
- (NPCM_I2CRXF_CTL_LAST_PEC & ioread8(bus->reg + NPCM_I2CRXF_CTL)))
+ (bus->data->rxf_ctl_last_pec & ioread8(bus->reg + NPCM_I2CRXF_CTL)))
npcm_i2c_reset(bus);

/* after any xfer, successful or not, stall and EOB must be disabled */
@@ -2265,6 +2285,7 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
static struct regmap *gcr_regmap;
+ struct device *dev = &pdev->dev;
struct i2c_adapter *adap;
struct npcm_i2c *bus;
struct clk *i2c_clk;
@@ -2277,6 +2298,12 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)

bus->dev = &pdev->dev;

+ bus->data = of_device_get_match_data(dev);
+ if (!bus->data) {
+ dev_err(dev, "OF data missing\n");
+ return -EINVAL;
+ }
+
bus->num = of_alias_get_id(pdev->dev.of_node, "i2c");
/* core clk must be acquired to calculate module timing settings */
i2c_clk = devm_clk_get(&pdev->dev, NULL);
@@ -2290,7 +2317,7 @@ static int npcm_i2c_probe_bus(struct platform_device *pdev)

if (IS_ERR(gcr_regmap))
return PTR_ERR(gcr_regmap);
- regmap_write(gcr_regmap, NPCM_I2CSEGCTL, NPCM_I2CSEGCTL_INIT_VAL);
+ regmap_write(gcr_regmap, NPCM_I2CSEGCTL, bus->data->segctl_init_val);

bus->reg = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(bus->reg))
@@ -2352,7 +2379,8 @@ static int npcm_i2c_remove_bus(struct platform_device *pdev)
}

static const struct of_device_id npcm_i2c_bus_of_table[] = {
- { .compatible = "nuvoton,npcm750-i2c", },
+ { .compatible = "nuvoton,npcm750-i2c", .data = &npxm7xx_i2c_data },
+ { .compatible = "nuvoton,npcm845-i2c", .data = &npxm8xx_i2c_data },
{}
};
MODULE_DEVICE_TABLE(of, npcm_i2c_bus_of_table);
--
2.17.1