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path: root/drivers/tty/serial/sh-sci.c
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Diffstat (limited to 'drivers/tty/serial/sh-sci.c')
-rw-r--r--drivers/tty/serial/sh-sci.c178
1 files changed, 129 insertions, 49 deletions
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 4646a9f53..0130feb06 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -84,6 +84,22 @@ enum SCI_CLKS {
SCI_NUM_CLKS
};
+/* Bit x set means sampling rate x + 1 is supported */
+#define SCI_SR(x) BIT((x) - 1)
+#define SCI_SR_RANGE(x, y) GENMASK((y) - 1, (x) - 1)
+
+#define SCI_SR_SCIFAB SCI_SR(5) | SCI_SR(7) | SCI_SR(11) | \
+ SCI_SR(13) | SCI_SR(16) | SCI_SR(17) | \
+ SCI_SR(19) | SCI_SR(27)
+
+#define min_sr(_port) ffs((_port)->sampling_rate_mask)
+#define max_sr(_port) fls((_port)->sampling_rate_mask)
+
+/* Iterate over all supported sampling rates, from high to low */
+#define for_each_sr(_sr, _port) \
+ for ((_sr) = max_sr(_port); (_sr) >= min_sr(_port); (_sr)--) \
+ if ((_port)->sampling_rate_mask & SCI_SR((_sr)))
+
struct sci_port {
struct uart_port port;
@@ -93,7 +109,7 @@ struct sci_port {
unsigned int overrun_mask;
unsigned int error_mask;
unsigned int error_clear;
- unsigned int sampling_rate;
+ unsigned int sampling_rate_mask;
resource_size_t reg_size;
/* Break timer */
@@ -637,7 +653,8 @@ static void sci_clear_SCxSR(struct uart_port *port, unsigned int mask)
}
}
-#if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_SH_SCI_CONSOLE)
+#if defined(CONFIG_CONSOLE_POLL) || defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
+ defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
#ifdef CONFIG_CONSOLE_POLL
static int sci_poll_get_char(struct uart_port *port)
@@ -678,7 +695,8 @@ static void sci_poll_put_char(struct uart_port *port, unsigned char c)
serial_port_out(port, SCxTDR, c);
sci_clear_SCxSR(port, SCxSR_TDxE_CLEAR(port) & ~SCxSR_TEND(port));
}
-#endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE */
+#endif /* CONFIG_CONSOLE_POLL || CONFIG_SERIAL_SH_SCI_CONSOLE ||
+ CONFIG_SERIAL_SH_SCI_EARLYCON */
static void sci_init_pins(struct uart_port *port, unsigned int cflag)
{
@@ -1902,19 +1920,13 @@ static int sci_sck_calc(struct sci_port *s, unsigned int bps,
unsigned int *srr)
{
unsigned long freq = s->clk_rates[SCI_SCK];
- unsigned int min_sr, max_sr, sr;
int err, min_err = INT_MAX;
+ unsigned int sr;
- if (s->sampling_rate) {
- /* SCI(F) has a fixed sampling rate */
- min_sr = max_sr = s->sampling_rate / 2;
- } else {
- /* HSCIF has a variable 1/(8..32) sampling rate */
- min_sr = 8;
- max_sr = 32;
- }
+ if (s->port.type != PORT_HSCIF)
+ freq *= 2;
- for (sr = max_sr; sr >= min_sr; sr--) {
+ for_each_sr(sr, s) {
err = DIV_ROUND_CLOSEST(freq, sr) - bps;
if (abs(err) >= abs(min_err))
continue;
@@ -1935,19 +1947,13 @@ static int sci_brg_calc(struct sci_port *s, unsigned int bps,
unsigned long freq, unsigned int *dlr,
unsigned int *srr)
{
- unsigned int min_sr, max_sr, sr, dl;
int err, min_err = INT_MAX;
+ unsigned int sr, dl;
- if (s->sampling_rate) {
- /* SCIF has a fixed sampling rate */
- min_sr = max_sr = s->sampling_rate / 2;
- } else {
- /* HSCIF has a variable 1/(8..32) sampling rate */
- min_sr = 8;
- max_sr = 32;
- }
+ if (s->port.type != PORT_HSCIF)
+ freq *= 2;
- for (sr = max_sr; sr >= min_sr; sr--) {
+ for_each_sr(sr, s) {
dl = DIV_ROUND_CLOSEST(freq, sr * bps);
dl = clamp(dl, 1U, 65535U);
@@ -1973,19 +1979,12 @@ static int sci_scbrr_calc(struct sci_port *s, unsigned int bps,
unsigned int *brr, unsigned int *srr,
unsigned int *cks)
{
- unsigned int min_sr, max_sr, shift, sr, br, prediv, scrate, c;
unsigned long freq = s->clk_rates[SCI_FCK];
+ unsigned int sr, br, prediv, scrate, c;
int err, min_err = INT_MAX;
- if (s->sampling_rate) {
- min_sr = max_sr = s->sampling_rate;
- shift = 0;
- } else {
- /* HSCIF has a variable sample rate */
- min_sr = 8;
- max_sr = 32;
- shift = 1;
- }
+ if (s->port.type != PORT_HSCIF)
+ freq *= 2;
/*
* Find the combination of sample rate and clock select with the
@@ -2002,10 +2001,10 @@ static int sci_scbrr_calc(struct sci_port *s, unsigned int bps,
* (|D - 0.5| / N * (1 + F))|
* NOTE: Usually, treat D for 0.5, F is 0 by this calculation.
*/
- for (sr = max_sr; sr >= min_sr; sr--) {
+ for_each_sr(sr, s) {
for (c = 0; c <= 3; c++) {
/* integerized formulas from HSCIF documentation */
- prediv = sr * (1 << (2 * c + shift));
+ prediv = sr * (1 << (2 * c + 1));
/*
* We need to calculate:
@@ -2062,7 +2061,7 @@ static void sci_reset(struct uart_port *port)
static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
struct ktermios *old)
{
- unsigned int baud, smr_val = 0, scr_val = 0, i;
+ unsigned int baud, smr_val = SCSMR_ASYNC, scr_val = 0, i;
unsigned int brr = 255, cks = 0, srr = 15, dl = 0, sccks = 0;
unsigned int brr1 = 255, cks1 = 0, srr1 = 15, dl1 = 0;
struct sci_port *s = to_sci_port(port);
@@ -2096,8 +2095,7 @@ static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
for (i = 0; i < SCI_NUM_CLKS; i++)
max_freq = max(max_freq, s->clk_rates[i]);
- baud = uart_get_baud_rate(port, termios, old, 0,
- max_freq / max(s->sampling_rate, 8U));
+ baud = uart_get_baud_rate(port, termios, old, 0, max_freq / min_sr(s));
if (!baud)
goto done;
@@ -2185,6 +2183,17 @@ done:
uart_update_timeout(port, termios->c_cflag, baud);
if (best_clk >= 0) {
+ if (port->type == PORT_SCIFA || port->type == PORT_SCIFB)
+ switch (srr + 1) {
+ case 5: smr_val |= SCSMR_SRC_5; break;
+ case 7: smr_val |= SCSMR_SRC_7; break;
+ case 11: smr_val |= SCSMR_SRC_11; break;
+ case 13: smr_val |= SCSMR_SRC_13; break;
+ case 16: smr_val |= SCSMR_SRC_16; break;
+ case 17: smr_val |= SCSMR_SRC_17; break;
+ case 19: smr_val |= SCSMR_SRC_19; break;
+ case 27: smr_val |= SCSMR_SRC_27; break;
+ }
smr_val |= cks;
dev_dbg(port->dev,
"SCR 0x%x SMR 0x%x BRR %u CKS 0x%x DL %u SRR %u\n",
@@ -2200,7 +2209,8 @@ done:
} else {
/* Don't touch the bit rate configuration */
scr_val = s->cfg->scscr & (SCSCR_CKE1 | SCSCR_CKE0);
- smr_val |= serial_port_in(port, SCSMR) & SCSMR_CKS;
+ smr_val |= serial_port_in(port, SCSMR) &
+ (SCSMR_CKEDG | SCSMR_SRC_MASK | SCSMR_CKS);
dev_dbg(port->dev, "SCR 0x%x SMR 0x%x\n", scr_val, smr_val);
serial_port_out(port, SCSCR, scr_val);
serial_port_out(port, SCSMR, smr_val);
@@ -2232,6 +2242,16 @@ done:
scr_val |= s->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0);
dev_dbg(port->dev, "SCSCR 0x%x\n", scr_val);
serial_port_out(port, SCSCR, scr_val);
+ if ((srr + 1 == 5) &&
+ (port->type == PORT_SCIFA || port->type == PORT_SCIFB)) {
+ /*
+ * In asynchronous mode, when the sampling rate is 1/5, first
+ * received data may become invalid on some SCIFA and SCIFB.
+ * To avoid this problem wait more than 1 serial data time (1
+ * bit time x serial data number) after setting SCSCR.RE = 1.
+ */
+ udelay(DIV_ROUND_UP(10 * 1000000, baud));
+ }
#ifdef CONFIG_SERIAL_SH_SCI_DMA
/*
@@ -2528,37 +2548,37 @@ static int sci_init_single(struct platform_device *dev,
port->fifosize = 256;
sci_port->overrun_reg = SCxSR;
sci_port->overrun_mask = SCIFA_ORER;
- sci_port->sampling_rate = 16;
+ sci_port->sampling_rate_mask = SCI_SR_SCIFAB;
break;
case PORT_HSCIF:
port->fifosize = 128;
sci_port->overrun_reg = SCLSR;
sci_port->overrun_mask = SCLSR_ORER;
- sci_port->sampling_rate = 0;
+ sci_port->sampling_rate_mask = SCI_SR_RANGE(8, 32);
break;
case PORT_SCIFA:
port->fifosize = 64;
sci_port->overrun_reg = SCxSR;
sci_port->overrun_mask = SCIFA_ORER;
- sci_port->sampling_rate = 16;
+ sci_port->sampling_rate_mask = SCI_SR_SCIFAB;
break;
case PORT_SCIF:
port->fifosize = 16;
if (p->regtype == SCIx_SH7705_SCIF_REGTYPE) {
sci_port->overrun_reg = SCxSR;
sci_port->overrun_mask = SCIFA_ORER;
- sci_port->sampling_rate = 16;
+ sci_port->sampling_rate_mask = SCI_SR(16);
} else {
sci_port->overrun_reg = SCLSR;
sci_port->overrun_mask = SCLSR_ORER;
- sci_port->sampling_rate = 32;
+ sci_port->sampling_rate_mask = SCI_SR(32);
}
break;
default:
port->fifosize = 1;
sci_port->overrun_reg = SCxSR;
sci_port->overrun_mask = SCI_ORER;
- sci_port->sampling_rate = 32;
+ sci_port->sampling_rate_mask = SCI_SR(32);
break;
}
@@ -2567,7 +2587,7 @@ static int sci_init_single(struct platform_device *dev,
* data override the sampling rate for now.
*/
if (p->sampling_rate)
- sci_port->sampling_rate = p->sampling_rate;
+ sci_port->sampling_rate_mask = SCI_SR(p->sampling_rate);
if (!early) {
ret = sci_init_clocks(sci_port, &dev->dev);
@@ -2632,7 +2652,8 @@ static void sci_cleanup_single(struct sci_port *port)
pm_runtime_disable(port->port.dev);
}
-#ifdef CONFIG_SERIAL_SH_SCI_CONSOLE
+#if defined(CONFIG_SERIAL_SH_SCI_CONSOLE) || \
+ defined(CONFIG_SERIAL_SH_SCI_EARLYCON)
static void serial_console_putchar(struct uart_port *port, int ch)
{
sci_poll_put_char(port, ch);
@@ -2652,9 +2673,12 @@ static void serial_console_write(struct console *co, const char *s,
int locked = 1;
local_irq_save(flags);
+#if defined(SUPPORT_SYSRQ)
if (port->sysrq)
locked = 0;
- else if (oops_in_progress)
+ else
+#endif
+ if (oops_in_progress)
locked = spin_trylock(&port->lock);
else
spin_lock(&port->lock);
@@ -2764,7 +2788,7 @@ static inline int sci_probe_earlyprintk(struct platform_device *pdev)
#define SCI_CONSOLE NULL
-#endif /* CONFIG_SERIAL_SH_SCI_CONSOLE */
+#endif /* CONFIG_SERIAL_SH_SCI_CONSOLE || CONFIG_SERIAL_SH_SCI_EARLYCON */
static const char banner[] __initconst = "SuperH (H)SCI(F) driver initialized";
@@ -2998,6 +3022,62 @@ static void __exit sci_exit(void)
early_platform_init_buffer("earlyprintk", &sci_driver,
early_serial_buf, ARRAY_SIZE(early_serial_buf));
#endif
+#ifdef CONFIG_SERIAL_SH_SCI_EARLYCON
+static struct __init plat_sci_port port_cfg;
+
+static int __init early_console_setup(struct earlycon_device *device,
+ int type)
+{
+ if (!device->port.membase)
+ return -ENODEV;
+
+ device->port.serial_in = sci_serial_in;
+ device->port.serial_out = sci_serial_out;
+ device->port.type = type;
+ memcpy(&sci_ports[0].port, &device->port, sizeof(struct uart_port));
+ sci_ports[0].cfg = &port_cfg;
+ sci_ports[0].cfg->type = type;
+ sci_probe_regmap(sci_ports[0].cfg);
+ port_cfg.scscr = sci_serial_in(&sci_ports[0].port, SCSCR) |
+ SCSCR_RE | SCSCR_TE;
+ sci_serial_out(&sci_ports[0].port, SCSCR, port_cfg.scscr);
+
+ device->con->write = serial_console_write;
+ return 0;
+}
+static int __init sci_early_console_setup(struct earlycon_device *device,
+ const char *opt)
+{
+ return early_console_setup(device, PORT_SCI);
+}
+static int __init scif_early_console_setup(struct earlycon_device *device,
+ const char *opt)
+{
+ return early_console_setup(device, PORT_SCIF);
+}
+static int __init scifa_early_console_setup(struct earlycon_device *device,
+ const char *opt)
+{
+ return early_console_setup(device, PORT_SCIFA);
+}
+static int __init scifb_early_console_setup(struct earlycon_device *device,
+ const char *opt)
+{
+ return early_console_setup(device, PORT_SCIFB);
+}
+static int __init hscif_early_console_setup(struct earlycon_device *device,
+ const char *opt)
+{
+ return early_console_setup(device, PORT_HSCIF);
+}
+
+OF_EARLYCON_DECLARE(sci, "renesas,sci", sci_early_console_setup);
+OF_EARLYCON_DECLARE(scif, "renesas,scif", scif_early_console_setup);
+OF_EARLYCON_DECLARE(scifa, "renesas,scifa", scifa_early_console_setup);
+OF_EARLYCON_DECLARE(scifb, "renesas,scifb", scifb_early_console_setup);
+OF_EARLYCON_DECLARE(hscif, "renesas,hscif", hscif_early_console_setup);
+#endif /* CONFIG_SERIAL_SH_SCI_EARLYCON */
+
module_init(sci_init);
module_exit(sci_exit);
generated by cgit v1.2.3-54-g00ecf (git 2.45.2) at 2024-07-03 05:20:16 +0000