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authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2016-01-08 08:04:46 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2016-01-08 08:04:46 +0300
commitf658f21c65d1d8a8c93d1a6505e86c285bb7897e (patch)
tree14e11203aab46747b95e07f871cc1d4ec4894d9e /drivers/tty
parentc93a59938c11f447ff2964ab3c317311778edf66 (diff)
parent192d367f218d0cd94aa9b5059992e4aa19ec5b36 (diff)
downloadlinux-f658f21c65d1d8a8c93d1a6505e86c285bb7897e.tar.xz
Merge branch 'scif-clk-sck-brg-for-v4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/renesas-drivers into tty-next
Geert writes: Summary: - Clean up the naming of clocks in the sh-sci driver and its DT bindings, - Add support for the optional external clock on (H)SCI(F), where this pin can serve as a clock input, - Add support for the optional clock sources for the Baud Rate Generator for External Clock (BRG), as found on some SCIF variants and on HSCIF.
Diffstat (limited to 'drivers/tty')
-rw-r--r--drivers/tty/serial/sh-sci.c555
-rw-r--r--drivers/tty/serial/sh-sci.h10
2 files changed, 413 insertions, 152 deletions
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 51c7507b0444..5f2a03acb5d9 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -2,6 +2,7 @@
* SuperH on-chip serial module support. (SCI with no FIFO / with FIFO)
*
* Copyright (C) 2002 - 2011 Paul Mundt
+ * Copyright (C) 2015 Glider bvba
* Modified to support SH7720 SCIF. Markus Brunner, Mark Jonas (Jul 2007).
*
* based off of the old drivers/char/sh-sci.c by:
@@ -76,6 +77,14 @@ enum {
((port)->irqs[SCIx_ERI_IRQ] && \
((port)->irqs[SCIx_RXI_IRQ] < 0))
+enum SCI_CLKS {
+ SCI_FCK, /* Functional Clock */
+ SCI_SCK, /* Optional External Clock */
+ SCI_BRG_INT, /* Optional BRG Internal Clock Source */
+ SCI_SCIF_CLK, /* Optional BRG External Clock Source */
+ SCI_NUM_CLKS
+};
+
struct sci_port {
struct uart_port port;
@@ -92,10 +101,9 @@ struct sci_port {
struct timer_list break_timer;
int break_flag;
- /* Interface clock */
- struct clk *iclk;
- /* Function clock */
- struct clk *fclk;
+ /* Clocks */
+ struct clk *clks[SCI_NUM_CLKS];
+ unsigned long clk_rates[SCI_NUM_CLKS];
int irqs[SCIx_NR_IRQS];
char *irqstr[SCIx_NR_IRQS];
@@ -163,6 +171,8 @@ static const struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
[HSSRR] = sci_reg_invalid,
[SCPCR] = sci_reg_invalid,
[SCPDR] = sci_reg_invalid,
+ [SCDL] = sci_reg_invalid,
+ [SCCKS] = sci_reg_invalid,
},
/*
@@ -185,6 +195,8 @@ static const struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
[HSSRR] = sci_reg_invalid,
[SCPCR] = sci_reg_invalid,
[SCPDR] = sci_reg_invalid,
+ [SCDL] = sci_reg_invalid,
+ [SCCKS] = sci_reg_invalid,
},
/*
@@ -206,6 +218,8 @@ static const struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
[HSSRR] = sci_reg_invalid,
[SCPCR] = { 0x30, 16 },
[SCPDR] = { 0x34, 16 },
+ [SCDL] = sci_reg_invalid,
+ [SCCKS] = sci_reg_invalid,
},
/*
@@ -227,6 +241,8 @@ static const struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
[HSSRR] = sci_reg_invalid,
[SCPCR] = { 0x30, 16 },
[SCPDR] = { 0x34, 16 },
+ [SCDL] = sci_reg_invalid,
+ [SCCKS] = sci_reg_invalid,
},
/*
@@ -249,6 +265,8 @@ static const struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
[HSSRR] = sci_reg_invalid,
[SCPCR] = sci_reg_invalid,
[SCPDR] = sci_reg_invalid,
+ [SCDL] = sci_reg_invalid,
+ [SCCKS] = sci_reg_invalid,
},
/*
@@ -270,6 +288,8 @@ static const struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
[HSSRR] = sci_reg_invalid,
[SCPCR] = sci_reg_invalid,
[SCPDR] = sci_reg_invalid,
+ [SCDL] = sci_reg_invalid,
+ [SCCKS] = sci_reg_invalid,
},
/*
@@ -291,6 +311,32 @@ static const struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
[HSSRR] = sci_reg_invalid,
[SCPCR] = sci_reg_invalid,
[SCPDR] = sci_reg_invalid,
+ [SCDL] = sci_reg_invalid,
+ [SCCKS] = sci_reg_invalid,
+ },
+
+ /*
+ * Common SCIF definitions for ports with a Baud Rate Generator for
+ * External Clock (BRG).
+ */
+ [SCIx_SH4_SCIF_BRG_REGTYPE] = {
+ [SCSMR] = { 0x00, 16 },
+ [SCBRR] = { 0x04, 8 },
+ [SCSCR] = { 0x08, 16 },
+ [SCxTDR] = { 0x0c, 8 },
+ [SCxSR] = { 0x10, 16 },
+ [SCxRDR] = { 0x14, 8 },
+ [SCFCR] = { 0x18, 16 },
+ [SCFDR] = { 0x1c, 16 },
+ [SCTFDR] = sci_reg_invalid,
+ [SCRFDR] = sci_reg_invalid,
+ [SCSPTR] = { 0x20, 16 },
+ [SCLSR] = { 0x24, 16 },
+ [HSSRR] = sci_reg_invalid,
+ [SCPCR] = sci_reg_invalid,
+ [SCPDR] = sci_reg_invalid,
+ [SCDL] = { 0x30, 16 },
+ [SCCKS] = { 0x34, 16 },
},
/*
@@ -312,6 +358,8 @@ static const struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
[HSSRR] = { 0x40, 16 },
[SCPCR] = sci_reg_invalid,
[SCPDR] = sci_reg_invalid,
+ [SCDL] = { 0x30, 16 },
+ [SCCKS] = { 0x34, 16 },
},
/*
@@ -334,6 +382,8 @@ static const struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
[HSSRR] = sci_reg_invalid,
[SCPCR] = sci_reg_invalid,
[SCPDR] = sci_reg_invalid,
+ [SCDL] = sci_reg_invalid,
+ [SCCKS] = sci_reg_invalid,
},
/*
@@ -356,6 +406,8 @@ static const struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
[HSSRR] = sci_reg_invalid,
[SCPCR] = sci_reg_invalid,
[SCPDR] = sci_reg_invalid,
+ [SCDL] = sci_reg_invalid,
+ [SCCKS] = sci_reg_invalid,
},
/*
@@ -378,6 +430,8 @@ static const struct plat_sci_reg sci_regmap[SCIx_NR_REGTYPES][SCIx_NR_REGS] = {
[HSSRR] = sci_reg_invalid,
[SCPCR] = sci_reg_invalid,
[SCPDR] = sci_reg_invalid,
+ [SCDL] = sci_reg_invalid,
+ [SCCKS] = sci_reg_invalid,
},
};
@@ -452,18 +506,24 @@ static int sci_probe_regmap(struct plat_sci_port *cfg)
static void sci_port_enable(struct sci_port *sci_port)
{
+ unsigned int i;
+
if (!sci_port->port.dev)
return;
pm_runtime_get_sync(sci_port->port.dev);
- clk_prepare_enable(sci_port->iclk);
- sci_port->port.uartclk = clk_get_rate(sci_port->iclk);
- clk_prepare_enable(sci_port->fclk);
+ for (i = 0; i < SCI_NUM_CLKS; i++) {
+ clk_prepare_enable(sci_port->clks[i]);
+ sci_port->clk_rates[i] = clk_get_rate(sci_port->clks[i]);
+ }
+ sci_port->port.uartclk = sci_port->clk_rates[SCI_FCK];
}
static void sci_port_disable(struct sci_port *sci_port)
{
+ unsigned int i;
+
if (!sci_port->port.dev)
return;
@@ -475,8 +535,8 @@ static void sci_port_disable(struct sci_port *sci_port)
del_timer_sync(&sci_port->break_timer);
sci_port->break_flag = 0;
- clk_disable_unprepare(sci_port->fclk);
- clk_disable_unprepare(sci_port->iclk);
+ for (i = SCI_NUM_CLKS; i-- > 0; )
+ clk_disable_unprepare(sci_port->clks[i]);
pm_runtime_put_sync(sci_port->port.dev);
}
@@ -1615,6 +1675,7 @@ static int sci_notifier(struct notifier_block *self,
{
struct sci_port *sci_port;
unsigned long flags;
+ unsigned int i;
sci_port = container_of(self, struct sci_port, freq_transition);
@@ -1622,7 +1683,9 @@ static int sci_notifier(struct notifier_block *self,
struct uart_port *port = &sci_port->port;
spin_lock_irqsave(&port->lock, flags);
- port->uartclk = clk_get_rate(sci_port->iclk);
+ for (i = 0; i < SCI_NUM_CLKS; i++)
+ sci_port->clk_rates[i] =
+ clk_get_rate(sci_port->clks[i]);
spin_unlock_irqrestore(&port->lock, flags);
}
@@ -1864,90 +1927,149 @@ static void sci_shutdown(struct uart_port *port)
sci_free_irq(s);
}
-static unsigned int sci_scbrr_calc(struct sci_port *s, unsigned int bps,
- unsigned long freq)
+static int sci_sck_calc(struct sci_port *s, unsigned int bps,
+ unsigned int *srr)
{
- if (s->sampling_rate)
- return DIV_ROUND_CLOSEST(freq, s->sampling_rate * bps) - 1;
+ unsigned long freq = s->clk_rates[SCI_SCK];
+ unsigned int min_sr, max_sr, sr;
+ int err, min_err = INT_MAX;
+
+ 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;
+ }
+
+ for (sr = max_sr; sr >= min_sr; sr--) {
+ err = DIV_ROUND_CLOSEST(freq, sr) - bps;
+ if (abs(err) >= abs(min_err))
+ continue;
+
+ min_err = err;
+ *srr = sr - 1;
- /* Warn, but use a safe default */
- WARN_ON(1);
+ if (!err)
+ break;
+ }
- return ((freq + 16 * bps) / (32 * bps) - 1);
+ dev_dbg(s->port.dev, "SCK: %u%+d bps using SR %u\n", bps, min_err,
+ *srr + 1);
+ return min_err;
}
-/* calculate frame length from SMR */
-static int sci_baud_calc_frame_len(unsigned int smr_val)
+static int sci_brg_calc(struct sci_port *s, unsigned int bps,
+ unsigned long freq, unsigned int *dlr,
+ unsigned int *srr)
{
- int len = 10;
+ unsigned int min_sr, max_sr, sr, dl;
+ int err, min_err = INT_MAX;
- if (smr_val & SCSMR_CHR)
- len--;
- if (smr_val & SCSMR_PE)
- len++;
- if (smr_val & SCSMR_STOP)
- len++;
+ 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;
+ }
- return len;
-}
+ for (sr = max_sr; sr >= min_sr; sr--) {
+ dl = DIV_ROUND_CLOSEST(freq, sr * bps);
+ dl = clamp(dl, 1U, 65535U);
+
+ err = DIV_ROUND_CLOSEST(freq, sr * dl) - bps;
+ if (abs(err) >= abs(min_err))
+ continue;
+
+ min_err = err;
+ *dlr = dl;
+ *srr = sr - 1;
+
+ if (!err)
+ break;
+ }
+ dev_dbg(s->port.dev, "BRG: %u%+d bps using DL %u SR %u\n", bps,
+ min_err, *dlr, *srr + 1);
+ return min_err;
+}
-/* calculate sample rate, BRR, and clock select for HSCIF */
-static void sci_baud_calc_hscif(unsigned int bps, unsigned long freq,
- int *brr, unsigned int *srr,
- unsigned int *cks, int frame_len)
+/* calculate sample rate, BRR, and clock select */
+static int sci_scbrr_calc(struct sci_port *s, unsigned int bps,
+ unsigned int *brr, unsigned int *srr,
+ unsigned int *cks)
{
- int sr, c, br, err, recv_margin;
- int min_err = 1000; /* 100% */
- int recv_max_margin = 0;
+ unsigned int min_sr, max_sr, shift, sr, br, prediv, scrate, c;
+ unsigned long freq = s->clk_rates[SCI_FCK];
+ int err, min_err = INT_MAX;
- /* Find the combination of sample rate and clock select with the
- smallest deviation from the desired baud rate. */
- for (sr = 8; sr <= 32; sr++) {
+ 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;
+ }
+
+ /*
+ * Find the combination of sample rate and clock select with the
+ * smallest deviation from the desired baud rate.
+ * Prefer high sample rates to maximise the receive margin.
+ *
+ * M: Receive margin (%)
+ * N: Ratio of bit rate to clock (N = sampling rate)
+ * D: Clock duty (D = 0 to 1.0)
+ * L: Frame length (L = 9 to 12)
+ * F: Absolute value of clock frequency deviation
+ *
+ * M = |(0.5 - 1 / 2 * N) - ((L - 0.5) * F) -
+ * (|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 (c = 0; c <= 3; c++) {
/* integerized formulas from HSCIF documentation */
- br = DIV_ROUND_CLOSEST(freq, (sr *
- (1 << (2 * c + 1)) * bps)) - 1;
- br = clamp(br, 0, 255);
- err = DIV_ROUND_CLOSEST(freq, ((br + 1) * bps * sr *
- (1 << (2 * c + 1)) / 1000)) -
- 1000;
- /* Calc recv margin
- * M: Receive margin (%)
- * N: Ratio of bit rate to clock (N = sampling rate)
- * D: Clock duty (D = 0 to 1.0)
- * L: Frame length (L = 9 to 12)
- * F: Absolute value of clock frequency deviation
+ prediv = sr * (1 << (2 * c + shift));
+
+ /*
+ * We need to calculate:
+ *
+ * br = freq / (prediv * bps) clamped to [1..256]
+ * err = freq / (br * prediv) - bps
*
- * M = |(0.5 - 1 / 2 * N) - ((L - 0.5) * F) -
- * (|D - 0.5| / N * (1 + F))|
- * NOTE: Usually, treat D for 0.5, F is 0 by this
- * calculation.
+ * Watch out for overflow when calculating the desired
+ * sampling clock rate!
*/
- recv_margin = abs((500 -
- DIV_ROUND_CLOSEST(1000, sr << 1)) / 10);
- if (abs(min_err) > abs(err)) {
- min_err = err;
- recv_max_margin = recv_margin;
- } else if ((min_err == err) &&
- (recv_margin > recv_max_margin))
- recv_max_margin = recv_margin;
- else
+ if (bps > UINT_MAX / prediv)
+ break;
+
+ scrate = prediv * bps;
+ br = DIV_ROUND_CLOSEST(freq, scrate);
+ br = clamp(br, 1U, 256U);
+
+ err = DIV_ROUND_CLOSEST(freq, br * prediv) - bps;
+ if (abs(err) >= abs(min_err))
continue;
- *brr = br;
+ min_err = err;
+ *brr = br - 1;
*srr = sr - 1;
*cks = c;
+
+ if (!err)
+ goto found;
}
}
- if (min_err == 1000) {
- WARN_ON(1);
- /* use defaults */
- *brr = 255;
- *srr = 15;
- *cks = 0;
- }
+found:
+ dev_dbg(s->port.dev, "BRR: %u%+d bps using N %u SR %u cks %u\n", bps,
+ min_err, *brr, *srr + 1, *cks);
+ return min_err;
}
static void sci_reset(struct uart_port *port)
@@ -1969,11 +2091,14 @@ 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 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);
const struct plat_sci_reg *reg;
- unsigned int baud, smr_val = 0, max_baud, cks = 0;
- int t = -1;
- unsigned int srr = 15;
+ int min_err = INT_MAX, err;
+ unsigned long max_freq = 0;
+ int best_clk = -1;
if ((termios->c_cflag & CSIZE) == CS7)
smr_val |= SCSMR_CHR;
@@ -1992,41 +2117,123 @@ static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
* that the previous boot loader has enabled required clocks and
* setup the baud rate generator hardware for us already.
*/
- max_baud = port->uartclk ? port->uartclk / 16 : 115200;
-
- baud = uart_get_baud_rate(port, termios, old, 0, max_baud);
- if (likely(baud && port->uartclk)) {
- if (s->cfg->type == PORT_HSCIF) {
- int frame_len = sci_baud_calc_frame_len(smr_val);
- sci_baud_calc_hscif(baud, port->uartclk, &t, &srr,
- &cks, frame_len);
- } else {
- t = sci_scbrr_calc(s, baud, port->uartclk);
- for (cks = 0; t >= 256 && cks <= 3; cks++)
- t >>= 2;
+ if (!port->uartclk) {
+ baud = uart_get_baud_rate(port, termios, old, 0, 115200);
+ goto done;
+ }
+
+ 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));
+ if (!baud)
+ goto done;
+
+ /*
+ * There can be multiple sources for the sampling clock. Find the one
+ * that gives us the smallest deviation from the desired baud rate.
+ */
+
+ /* Optional Undivided External Clock */
+ if (s->clk_rates[SCI_SCK] && port->type != PORT_SCIFA &&
+ port->type != PORT_SCIFB) {
+ err = sci_sck_calc(s, baud, &srr1);
+ if (abs(err) < abs(min_err)) {
+ best_clk = SCI_SCK;
+ scr_val = SCSCR_CKE1;
+ sccks = SCCKS_CKS;
+ min_err = err;
+ srr = srr1;
+ if (!err)
+ goto done;
+ }
+ }
+
+ /* Optional BRG Frequency Divided External Clock */
+ if (s->clk_rates[SCI_SCIF_CLK] && sci_getreg(port, SCDL)->size) {
+ err = sci_brg_calc(s, baud, s->clk_rates[SCI_SCIF_CLK], &dl1,
+ &srr1);
+ if (abs(err) < abs(min_err)) {
+ best_clk = SCI_SCIF_CLK;
+ scr_val = SCSCR_CKE1;
+ sccks = 0;
+ min_err = err;
+ dl = dl1;
+ srr = srr1;
+ if (!err)
+ goto done;
+ }
+ }
+
+ /* Optional BRG Frequency Divided Internal Clock */
+ if (s->clk_rates[SCI_BRG_INT] && sci_getreg(port, SCDL)->size) {
+ err = sci_brg_calc(s, baud, s->clk_rates[SCI_BRG_INT], &dl1,
+ &srr1);
+ if (abs(err) < abs(min_err)) {
+ best_clk = SCI_BRG_INT;
+ scr_val = SCSCR_CKE1;
+ sccks = SCCKS_XIN;
+ min_err = err;
+ dl = dl1;
+ srr = srr1;
+ if (!min_err)
+ goto done;
}
}
+ /* Divided Functional Clock using standard Bit Rate Register */
+ err = sci_scbrr_calc(s, baud, &brr1, &srr1, &cks1);
+ if (abs(err) < abs(min_err)) {
+ best_clk = SCI_FCK;
+ scr_val = 0;
+ min_err = err;
+ brr = brr1;
+ srr = srr1;
+ cks = cks1;
+ }
+
+done:
+ if (best_clk >= 0)
+ dev_dbg(port->dev, "Using clk %pC for %u%+d bps\n",
+ s->clks[best_clk], baud, min_err);
+
sci_port_enable(s);
- sci_reset(port);
+ /*
+ * Program the optional External Baud Rate Generator (BRG) first.
+ * It controls the mux to select (H)SCK or frequency divided clock.
+ */
+ if (best_clk >= 0 && sci_getreg(port, SCCKS)->size) {
+ serial_port_out(port, SCDL, dl);
+ serial_port_out(port, SCCKS, sccks);
+ }
- smr_val |= serial_port_in(port, SCSMR) & SCSMR_CKS;
+ sci_reset(port);
uart_update_timeout(port, termios->c_cflag, baud);
- dev_dbg(port->dev, "%s: SMR %x, cks %x, t %x, SCSCR %x\n",
- __func__, smr_val, cks, t, s->cfg->scscr);
-
- if (t >= 0) {
- serial_port_out(port, SCSMR, (smr_val & ~SCSMR_CKS) | cks);
- serial_port_out(port, SCBRR, t);
- reg = sci_getreg(port, HSSRR);
- if (reg->size)
+ if (best_clk >= 0) {
+ smr_val |= cks;
+ dev_dbg(port->dev,
+ "SCR 0x%x SMR 0x%x BRR %u CKS 0x%x DL %u SRR %u\n",
+ scr_val, smr_val, brr, sccks, dl, srr);
+ serial_port_out(port, SCSCR, scr_val);
+ serial_port_out(port, SCSMR, smr_val);
+ serial_port_out(port, SCBRR, brr);
+ if (sci_getreg(port, HSSRR)->size)
serial_port_out(port, HSSRR, srr | HSCIF_SRE);
- udelay((1000000+(baud-1)) / baud); /* Wait one bit interval */
- } else
+
+ /* Wait one bit interval */
+ udelay((1000000 + (baud - 1)) / baud);
+ } 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;
+ 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);
+ }
sci_init_pins(port, termios->c_cflag);
@@ -2051,7 +2258,9 @@ static void sci_set_termios(struct uart_port *port, struct ktermios *termios,
serial_port_out(port, SCFCR, ctrl);
}
- serial_port_out(port, SCSCR, s->cfg->scscr);
+ 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);
#ifdef CONFIG_SERIAL_SH_SCI_DMA
/*
@@ -2241,6 +2450,63 @@ static struct uart_ops sci_uart_ops = {
#endif
};
+static int sci_init_clocks(struct sci_port *sci_port, struct device *dev)
+{
+ const char *clk_names[] = {
+ [SCI_FCK] = "fck",
+ [SCI_SCK] = "sck",
+ [SCI_BRG_INT] = "brg_int",
+ [SCI_SCIF_CLK] = "scif_clk",
+ };
+ struct clk *clk;
+ unsigned int i;
+
+ if (sci_port->cfg->type == PORT_HSCIF)
+ clk_names[SCI_SCK] = "hsck";
+
+ for (i = 0; i < SCI_NUM_CLKS; i++) {
+ clk = devm_clk_get(dev, clk_names[i]);
+ if (PTR_ERR(clk) == -EPROBE_DEFER)
+ return -EPROBE_DEFER;
+
+ if (IS_ERR(clk) && i == SCI_FCK) {
+ /*
+ * "fck" used to be called "sci_ick", and we need to
+ * maintain DT backward compatibility.
+ */
+ clk = devm_clk_get(dev, "sci_ick");
+ if (PTR_ERR(clk) == -EPROBE_DEFER)
+ return -EPROBE_DEFER;
+
+ if (!IS_ERR(clk))
+ goto found;
+
+ /*
+ * Not all SH platforms declare a clock lookup entry
+ * for SCI devices, in which case we need to get the
+ * global "peripheral_clk" clock.
+ */
+ clk = devm_clk_get(dev, "peripheral_clk");
+ if (!IS_ERR(clk))
+ goto found;
+
+ dev_err(dev, "failed to get %s (%ld)\n", clk_names[i],
+ PTR_ERR(clk));
+ return PTR_ERR(clk);
+ }
+
+found:
+ if (IS_ERR(clk))
+ dev_dbg(dev, "failed to get %s (%ld)\n", clk_names[i],
+ PTR_ERR(clk));
+ else
+ dev_dbg(dev, "clk %s is %pC rate %pCr\n", clk_names[i],
+ clk, clk);
+ sci_port->clks[i] = IS_ERR(clk) ? NULL : clk;
+ }
+ return 0;
+}
+
static int sci_init_single(struct platform_device *dev,
struct sci_port *sci_port, unsigned int index,
struct plat_sci_port *p, bool early)
@@ -2333,22 +2599,9 @@ static int sci_init_single(struct platform_device *dev,
sci_port->sampling_rate = p->sampling_rate;
if (!early) {
- sci_port->iclk = clk_get(&dev->dev, "sci_ick");
- if (IS_ERR(sci_port->iclk)) {
- sci_port->iclk = clk_get(&dev->dev, "peripheral_clk");
- if (IS_ERR(sci_port->iclk)) {
- dev_err(&dev->dev, "can't get iclk\n");
- return PTR_ERR(sci_port->iclk);
- }
- }
-
- /*
- * The function clock is optional, ignore it if we can't
- * find it.
- */
- sci_port->fclk = clk_get(&dev->dev, "sci_fck");
- if (IS_ERR(sci_port->fclk))
- sci_port->fclk = NULL;
+ ret = sci_init_clocks(sci_port, &dev->dev);
+ if (ret < 0)
+ return ret;
port->dev = &dev->dev;
@@ -2405,9 +2658,6 @@ static int sci_init_single(struct platform_device *dev,
static void sci_cleanup_single(struct sci_port *port)
{
- clk_put(port->iclk);
- clk_put(port->fclk);
-
pm_runtime_disable(port->port.dev);
}
@@ -2426,7 +2676,7 @@ static void serial_console_write(struct console *co, const char *s,
{
struct sci_port *sci_port = &sci_ports[co->index];
struct uart_port *port = &sci_port->port;
- unsigned short bits, ctrl;
+ unsigned short bits, ctrl, ctrl_temp;
unsigned long flags;
int locked = 1;
@@ -2438,9 +2688,11 @@ static void serial_console_write(struct console *co, const char *s,
else
spin_lock(&port->lock);
- /* first save the SCSCR then disable the interrupts */
+ /* first save SCSCR then disable interrupts, keep clock source */
ctrl = serial_port_in(port, SCSCR);
- serial_port_out(port, SCSCR, sci_port->cfg->scscr);
+ ctrl_temp = (sci_port->cfg->scscr & ~(SCSCR_CKE1 | SCSCR_CKE0)) |
+ (ctrl & (SCSCR_CKE1 | SCSCR_CKE0));
+ serial_port_out(port, SCSCR, ctrl_temp);
uart_console_write(port, s, count, serial_console_putchar);
@@ -2569,42 +2821,44 @@ static int sci_remove(struct platform_device *dev)
return 0;
}
-struct sci_port_info {
- unsigned int type;
- unsigned int regtype;
-};
+
+#define SCI_OF_DATA(type, regtype) (void *)((type) << 16 | (regtype))
+#define SCI_OF_TYPE(data) ((unsigned long)(data) >> 16)
+#define SCI_OF_REGTYPE(data) ((unsigned long)(data) & 0xffff)
static const struct of_device_id of_sci_match[] = {
+ /* SoC-specific types */
+ {
+ .compatible = "renesas,scif-r7s72100",
+ .data = SCI_OF_DATA(PORT_SCIF, SCIx_SH2_SCIF_FIFODATA_REGTYPE),
+ },
+ /* Family-specific types */
+ {
+ .compatible = "renesas,rcar-gen1-scif",
+ .data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
+ }, {
+ .compatible = "renesas,rcar-gen2-scif",
+ .data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
+ }, {
+ .compatible = "renesas,rcar-gen3-scif",
+ .data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_BRG_REGTYPE),
+ },
+ /* Generic types */
{
.compatible = "renesas,scif",
- .data = &(const struct sci_port_info) {
- .type = PORT_SCIF,
- .regtype = SCIx_SH4_SCIF_REGTYPE,
- },
+ .data = SCI_OF_DATA(PORT_SCIF, SCIx_SH4_SCIF_REGTYPE),
}, {
.compatible = "renesas,scifa",
- .data = &(const struct sci_port_info) {
- .type = PORT_SCIFA,
- .regtype = SCIx_SCIFA_REGTYPE,
- },
+ .data = SCI_OF_DATA(PORT_SCIFA, SCIx_SCIFA_REGTYPE),
}, {
.compatible = "renesas,scifb",
- .data = &(const struct sci_port_info) {
- .type = PORT_SCIFB,
- .regtype = SCIx_SCIFB_REGTYPE,
- },
+ .data = SCI_OF_DATA(PORT_SCIFB, SCIx_SCIFB_REGTYPE),
}, {
.compatible = "renesas,hscif",
- .data = &(const struct sci_port_info) {
- .type = PORT_HSCIF,
- .regtype = SCIx_HSCIF_REGTYPE,
- },
+ .data = SCI_OF_DATA(PORT_HSCIF, SCIx_HSCIF_REGTYPE),
}, {
.compatible = "renesas,sci",
- .data = &(const struct sci_port_info) {
- .type = PORT_SCI,
- .regtype = SCIx_SCI_REGTYPE,
- },
+ .data = SCI_OF_DATA(PORT_SCI, SCIx_SCI_REGTYPE),
}, {
/* Terminator */
},
@@ -2616,24 +2870,21 @@ sci_parse_dt(struct platform_device *pdev, unsigned int *dev_id)
{
struct device_node *np = pdev->dev.of_node;
const struct of_device_id *match;
- const struct sci_port_info *info;
struct plat_sci_port *p;
int id;
if (!IS_ENABLED(CONFIG_OF) || !np)
return NULL;
- match = of_match_node(of_sci_match, pdev->dev.of_node);
+ match = of_match_node(of_sci_match, np);
if (!match)
return NULL;
- info = match->data;
-
p = devm_kzalloc(&pdev->dev, sizeof(struct plat_sci_port), GFP_KERNEL);
if (!p)
return NULL;
- /* Get the line number for the aliases node. */
+ /* Get the line number from the aliases node. */
id = of_alias_get_id(np, "serial");
if (id < 0) {
dev_err(&pdev->dev, "failed to get alias id (%d)\n", id);
@@ -2643,8 +2894,8 @@ sci_parse_dt(struct platform_device *pdev, unsigned int *dev_id)
*dev_id = id;
p->flags = UPF_IOREMAP | UPF_BOOT_AUTOCONF;
- p->type = info->type;
- p->regtype = info->regtype;
+ p->type = SCI_OF_TYPE(match->data);
+ p->regtype = SCI_OF_REGTYPE(match->data);
p->scscr = SCSCR_RE | SCSCR_TE;
return p;
diff --git a/drivers/tty/serial/sh-sci.h b/drivers/tty/serial/sh-sci.h
index bf69bbdcc1f9..fb1760250421 100644
--- a/drivers/tty/serial/sh-sci.h
+++ b/drivers/tty/serial/sh-sci.h
@@ -27,6 +27,8 @@ enum {
HSSRR, /* Sampling Rate Register */
SCPCR, /* Serial Port Control Register */
SCPDR, /* Serial Port Data Register */
+ SCDL, /* BRG Frequency Division Register */
+ SCCKS, /* BRG Clock Select Register */
SCIx_NR_REGS,
};
@@ -109,6 +111,14 @@ enum {
#define SCPDR_RTSD BIT(4) /* Serial Port RTS Output Pin Data */
#define SCPDR_CTSD BIT(3) /* Serial Port CTS Input Pin Data */
+/*
+ * BRG Clock Select Register (Some SCIF and HSCIF)
+ * The Baud Rate Generator for external clock can provide a clock source for
+ * the sampling clock. It outputs either its frequency divided clock, or the
+ * (undivided) (H)SCK external clock.
+ */
+#define SCCKS_CKS BIT(15) /* Select (H)SCK (1) or divided SC_CLK (0) */
+#define SCCKS_XIN BIT(14) /* SC_CLK uses bus clock (1) or SCIF_CLK (0) */
#define SCxSR_TEND(port) (((port)->type == PORT_SCI) ? SCI_TEND : SCIF_TEND)
#define SCxSR_RDxF(port) (((port)->type == PORT_SCI) ? SCI_RDRF : SCIF_RDF)