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path: root/drivers/tty/serial/8250/8250_dw.c
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Diffstat (limited to 'drivers/tty/serial/8250/8250_dw.c')
-rw-r--r--drivers/tty/serial/8250/8250_dw.c423
1 files changed, 208 insertions, 215 deletions
diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index 176f18f2e..b022f5a01 100644
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -56,7 +56,6 @@
struct dw8250_data {
u8 usr_reg;
- int last_mcr;
int line;
int msr_mask_on;
int msr_mask_off;
@@ -64,24 +63,15 @@ struct dw8250_data {
struct clk *pclk;
struct reset_control *rst;
struct uart_8250_dma dma;
-};
-#define BYT_PRV_CLK 0x800
-#define BYT_PRV_CLK_EN (1 << 0)
-#define BYT_PRV_CLK_M_VAL_SHIFT 1
-#define BYT_PRV_CLK_N_VAL_SHIFT 16
-#define BYT_PRV_CLK_UPDATE (1 << 31)
+ unsigned int skip_autocfg:1;
+ unsigned int uart_16550_compatible:1;
+};
static inline int dw8250_modify_msr(struct uart_port *p, int offset, int value)
{
struct dw8250_data *d = p->private_data;
- /* If reading MSR, report CTS asserted when auto-CTS/RTS enabled */
- if (offset == UART_MSR && d->last_mcr & UART_MCR_AFE) {
- value |= UART_MSR_CTS;
- value &= ~UART_MSR_DCTS;
- }
-
/* Override any modem control signals if needed */
if (offset == UART_MSR) {
value |= d->msr_mask_on;
@@ -99,30 +89,46 @@ static void dw8250_force_idle(struct uart_port *p)
(void)p->serial_in(p, UART_RX);
}
+static void dw8250_check_lcr(struct uart_port *p, int value)
+{
+ void __iomem *offset = p->membase + (UART_LCR << p->regshift);
+ int tries = 1000;
+
+ /* Make sure LCR write wasn't ignored */
+ while (tries--) {
+ unsigned int lcr = p->serial_in(p, UART_LCR);
+
+ if ((value & ~UART_LCR_SPAR) == (lcr & ~UART_LCR_SPAR))
+ return;
+
+ dw8250_force_idle(p);
+
+#ifdef CONFIG_64BIT
+ if (p->type == PORT_OCTEON)
+ __raw_writeq(value & 0xff, offset);
+ else
+#endif
+ if (p->iotype == UPIO_MEM32)
+ writel(value, offset);
+ else if (p->iotype == UPIO_MEM32BE)
+ iowrite32be(value, offset);
+ else
+ writeb(value, offset);
+ }
+ /*
+ * FIXME: this deadlocks if port->lock is already held
+ * dev_err(p->dev, "Couldn't set LCR to %d\n", value);
+ */
+}
+
static void dw8250_serial_out(struct uart_port *p, int offset, int value)
{
struct dw8250_data *d = p->private_data;
- if (offset == UART_MCR)
- d->last_mcr = value;
-
writeb(value, p->membase + (offset << p->regshift));
- /* Make sure LCR write wasn't ignored */
- if (offset == UART_LCR) {
- int tries = 1000;
- while (tries--) {
- unsigned int lcr = p->serial_in(p, UART_LCR);
- if ((value & ~UART_LCR_SPAR) == (lcr & ~UART_LCR_SPAR))
- return;
- dw8250_force_idle(p);
- writeb(value, p->membase + (UART_LCR << p->regshift));
- }
- /*
- * FIXME: this deadlocks if port->lock is already held
- * dev_err(p->dev, "Couldn't set LCR to %d\n", value);
- */
- }
+ if (offset == UART_LCR && !d->uart_16550_compatible)
+ dw8250_check_lcr(p, value);
}
static unsigned int dw8250_serial_in(struct uart_port *p, int offset)
@@ -146,30 +152,13 @@ static void dw8250_serial_outq(struct uart_port *p, int offset, int value)
{
struct dw8250_data *d = p->private_data;
- if (offset == UART_MCR)
- d->last_mcr = value;
-
value &= 0xff;
__raw_writeq(value, p->membase + (offset << p->regshift));
/* Read back to ensure register write ordering. */
__raw_readq(p->membase + (UART_LCR << p->regshift));
- /* Make sure LCR write wasn't ignored */
- if (offset == UART_LCR) {
- int tries = 1000;
- while (tries--) {
- unsigned int lcr = p->serial_in(p, UART_LCR);
- if ((value & ~UART_LCR_SPAR) == (lcr & ~UART_LCR_SPAR))
- return;
- dw8250_force_idle(p);
- __raw_writeq(value & 0xff,
- p->membase + (UART_LCR << p->regshift));
- }
- /*
- * FIXME: this deadlocks if port->lock is already held
- * dev_err(p->dev, "Couldn't set LCR to %d\n", value);
- */
- }
+ if (offset == UART_LCR && !d->uart_16550_compatible)
+ dw8250_check_lcr(p, value);
}
#endif /* CONFIG_64BIT */
@@ -177,26 +166,10 @@ static void dw8250_serial_out32(struct uart_port *p, int offset, int value)
{
struct dw8250_data *d = p->private_data;
- if (offset == UART_MCR)
- d->last_mcr = value;
-
writel(value, p->membase + (offset << p->regshift));
- /* Make sure LCR write wasn't ignored */
- if (offset == UART_LCR) {
- int tries = 1000;
- while (tries--) {
- unsigned int lcr = p->serial_in(p, UART_LCR);
- if ((value & ~UART_LCR_SPAR) == (lcr & ~UART_LCR_SPAR))
- return;
- dw8250_force_idle(p);
- writel(value, p->membase + (UART_LCR << p->regshift));
- }
- /*
- * FIXME: this deadlocks if port->lock is already held
- * dev_err(p->dev, "Couldn't set LCR to %d\n", value);
- */
- }
+ if (offset == UART_LCR && !d->uart_16550_compatible)
+ dw8250_check_lcr(p, value);
}
static unsigned int dw8250_serial_in32(struct uart_port *p, int offset)
@@ -206,14 +179,33 @@ static unsigned int dw8250_serial_in32(struct uart_port *p, int offset)
return dw8250_modify_msr(p, offset, value);
}
+static void dw8250_serial_out32be(struct uart_port *p, int offset, int value)
+{
+ struct dw8250_data *d = p->private_data;
+
+ iowrite32be(value, p->membase + (offset << p->regshift));
+
+ if (offset == UART_LCR && !d->uart_16550_compatible)
+ dw8250_check_lcr(p, value);
+}
+
+static unsigned int dw8250_serial_in32be(struct uart_port *p, int offset)
+{
+ unsigned int value = ioread32be(p->membase + (offset << p->regshift));
+
+ return dw8250_modify_msr(p, offset, value);
+}
+
+
static int dw8250_handle_irq(struct uart_port *p)
{
struct dw8250_data *d = p->private_data;
unsigned int iir = p->serial_in(p, UART_IIR);
- if (serial8250_handle_irq(p, iir)) {
+ if (serial8250_handle_irq(p, iir))
return 1;
- } else if ((iir & UART_IIR_BUSY) == UART_IIR_BUSY) {
+
+ if ((iir & UART_IIR_BUSY) == UART_IIR_BUSY) {
/* Clear the USR */
(void)p->serial_in(p, d->usr_reg);
@@ -246,10 +238,6 @@ static void dw8250_set_termios(struct uart_port *p, struct ktermios *termios,
if (IS_ERR(d->clk) || !old)
goto out;
- /* Not requesting clock rates below 1.8432Mhz */
- if (baud < 115200)
- baud = 115200;
-
clk_disable_unprepare(d->clk);
rate = clk_round_rate(d->clk, baud * 16);
ret = clk_set_rate(d->clk, rate);
@@ -257,31 +245,100 @@ static void dw8250_set_termios(struct uart_port *p, struct ktermios *termios,
if (!ret)
p->uartclk = rate;
+
+ p->status &= ~UPSTAT_AUTOCTS;
+ if (termios->c_cflag & CRTSCTS)
+ p->status |= UPSTAT_AUTOCTS;
+
out:
serial8250_do_set_termios(p, termios, old);
}
-static bool dw8250_dma_filter(struct dma_chan *chan, void *param)
+/*
+ * dw8250_fallback_dma_filter will prevent the UART from getting just any free
+ * channel on platforms that have DMA engines, but don't have any channels
+ * assigned to the UART.
+ *
+ * REVISIT: This is a work around for limitation in the DMA Engine API. Once the
+ * core problem is fixed, this function is no longer needed.
+ */
+static bool dw8250_fallback_dma_filter(struct dma_chan *chan, void *param)
{
return false;
}
-static void dw8250_setup_port(struct uart_8250_port *up)
+static bool dw8250_idma_filter(struct dma_chan *chan, void *param)
+{
+ return param == chan->device->dev->parent;
+}
+
+static void dw8250_quirks(struct uart_port *p, struct dw8250_data *data)
{
- struct uart_port *p = &up->port;
- u32 reg = readl(p->membase + DW_UART_UCV);
+ if (p->dev->of_node) {
+ struct device_node *np = p->dev->of_node;
+ int id;
+
+ /* get index of serial line, if found in DT aliases */
+ id = of_alias_get_id(np, "serial");
+ if (id >= 0)
+ p->line = id;
+#ifdef CONFIG_64BIT
+ if (of_device_is_compatible(np, "cavium,octeon-3860-uart")) {
+ p->serial_in = dw8250_serial_inq;
+ p->serial_out = dw8250_serial_outq;
+ p->flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_FIXED_TYPE;
+ p->type = PORT_OCTEON;
+ data->usr_reg = 0x27;
+ data->skip_autocfg = true;
+ }
+#endif
+ if (of_device_is_big_endian(p->dev->of_node)) {
+ p->iotype = UPIO_MEM32BE;
+ p->serial_in = dw8250_serial_in32be;
+ p->serial_out = dw8250_serial_out32be;
+ }
+ } else if (has_acpi_companion(p->dev)) {
+ p->iotype = UPIO_MEM32;
+ p->regshift = 2;
+ p->serial_in = dw8250_serial_in32;
+ p->set_termios = dw8250_set_termios;
+ /* So far none of there implement the Busy Functionality */
+ data->uart_16550_compatible = true;
+ }
+
+ /* Platforms with iDMA */
+ if (platform_get_resource_byname(to_platform_device(p->dev),
+ IORESOURCE_MEM, "lpss_priv")) {
+ p->set_termios = dw8250_set_termios;
+ data->dma.rx_param = p->dev->parent;
+ data->dma.tx_param = p->dev->parent;
+ data->dma.fn = dw8250_idma_filter;
+ }
+}
+
+static void dw8250_setup_port(struct uart_port *p)
+{
+ struct uart_8250_port *up = up_to_u8250p(p);
+ u32 reg;
/*
* If the Component Version Register returns zero, we know that
* ADDITIONAL_FEATURES are not enabled. No need to go any further.
*/
+ if (p->iotype == UPIO_MEM32BE)
+ reg = ioread32be(p->membase + DW_UART_UCV);
+ else
+ reg = readl(p->membase + DW_UART_UCV);
if (!reg)
return;
- dev_dbg_ratelimited(p->dev, "Designware UART version %c.%c%c\n",
+ dev_dbg(p->dev, "Designware UART version %c.%c%c\n",
(reg >> 24) & 0xff, (reg >> 16) & 0xff, (reg >> 8) & 0xff);
- reg = readl(p->membase + DW_UART_CPR);
+ if (p->iotype == UPIO_MEM32BE)
+ reg = ioread32be(p->membase + DW_UART_CPR);
+ else
+ reg = readl(p->membase + DW_UART_CPR);
if (!reg)
return;
@@ -290,7 +347,6 @@ static void dw8250_setup_port(struct uart_8250_port *up)
p->type = PORT_16550A;
p->flags |= UPF_FIXED_TYPE;
p->fifosize = DW_UART_CPR_FIFO_SIZE(reg);
- up->tx_loadsz = p->fifosize;
up->capabilities = UART_CAP_FIFO;
}
@@ -298,149 +354,91 @@ static void dw8250_setup_port(struct uart_8250_port *up)
up->capabilities |= UART_CAP_AFE;
}
-static int dw8250_probe_of(struct uart_port *p,
- struct dw8250_data *data)
+static int dw8250_probe(struct platform_device *pdev)
{
- struct device_node *np = p->dev->of_node;
- struct uart_8250_port *up = up_to_u8250p(p);
- u32 val;
- bool has_ucv = true;
- int id;
+ struct uart_8250_port uart = {};
+ struct resource *regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ int irq = platform_get_irq(pdev, 0);
+ struct uart_port *p = &uart.port;
+ struct dw8250_data *data;
+ int err;
+ u32 val;
-#ifdef CONFIG_64BIT
- if (of_device_is_compatible(np, "cavium,octeon-3860-uart")) {
- p->serial_in = dw8250_serial_inq;
- p->serial_out = dw8250_serial_outq;
- p->flags = UPF_SKIP_TEST | UPF_SHARE_IRQ | UPF_FIXED_TYPE;
- p->type = PORT_OCTEON;
- data->usr_reg = 0x27;
- has_ucv = false;
- } else
-#endif
- if (!of_property_read_u32(np, "reg-io-width", &val)) {
- switch (val) {
- case 1:
- break;
- case 4:
- p->iotype = UPIO_MEM32;
- p->serial_in = dw8250_serial_in32;
- p->serial_out = dw8250_serial_out32;
- break;
- default:
- dev_err(p->dev, "unsupported reg-io-width (%u)\n", val);
- return -EINVAL;
- }
+ if (!regs) {
+ dev_err(&pdev->dev, "no registers defined\n");
+ return -EINVAL;
}
- if (has_ucv)
- dw8250_setup_port(up);
-
- /* if we have a valid fifosize, try hooking up DMA here */
- if (p->fifosize) {
- up->dma = &data->dma;
- up->dma->rxconf.src_maxburst = p->fifosize / 4;
- up->dma->txconf.dst_maxburst = p->fifosize / 4;
+ if (irq < 0) {
+ if (irq != -EPROBE_DEFER)
+ dev_err(&pdev->dev, "cannot get irq\n");
+ return irq;
}
- if (!of_property_read_u32(np, "reg-shift", &val))
+ spin_lock_init(&p->lock);
+ p->mapbase = regs->start;
+ p->irq = irq;
+ p->handle_irq = dw8250_handle_irq;
+ p->pm = dw8250_do_pm;
+ p->type = PORT_8250;
+ p->flags = UPF_SHARE_IRQ | UPF_FIXED_PORT;
+ p->dev = &pdev->dev;
+ p->iotype = UPIO_MEM;
+ p->serial_in = dw8250_serial_in;
+ p->serial_out = dw8250_serial_out;
+
+ p->membase = devm_ioremap(&pdev->dev, regs->start, resource_size(regs));
+ if (!p->membase)
+ return -ENOMEM;
+
+ data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->dma.fn = dw8250_fallback_dma_filter;
+ data->usr_reg = DW_UART_USR;
+ p->private_data = data;
+
+ data->uart_16550_compatible = device_property_read_bool(p->dev,
+ "snps,uart-16550-compatible");
+
+ err = device_property_read_u32(p->dev, "reg-shift", &val);
+ if (!err)
p->regshift = val;
- /* get index of serial line, if found in DT aliases */
- id = of_alias_get_id(np, "serial");
- if (id >= 0)
- p->line = id;
+ err = device_property_read_u32(p->dev, "reg-io-width", &val);
+ if (!err && val == 4) {
+ p->iotype = UPIO_MEM32;
+ p->serial_in = dw8250_serial_in32;
+ p->serial_out = dw8250_serial_out32;
+ }
- if (of_property_read_bool(np, "dcd-override")) {
+ if (device_property_read_bool(p->dev, "dcd-override")) {
/* Always report DCD as active */
data->msr_mask_on |= UART_MSR_DCD;
data->msr_mask_off |= UART_MSR_DDCD;
}
- if (of_property_read_bool(np, "dsr-override")) {
+ if (device_property_read_bool(p->dev, "dsr-override")) {
/* Always report DSR as active */
data->msr_mask_on |= UART_MSR_DSR;
data->msr_mask_off |= UART_MSR_DDSR;
}
- if (of_property_read_bool(np, "cts-override")) {
+ if (device_property_read_bool(p->dev, "cts-override")) {
/* Always report CTS as active */
data->msr_mask_on |= UART_MSR_CTS;
data->msr_mask_off |= UART_MSR_DCTS;
}
- if (of_property_read_bool(np, "ri-override")) {
+ if (device_property_read_bool(p->dev, "ri-override")) {
/* Always report Ring indicator as inactive */
data->msr_mask_off |= UART_MSR_RI;
data->msr_mask_off |= UART_MSR_TERI;
}
- return 0;
-}
-
-static int dw8250_probe_acpi(struct uart_8250_port *up,
- struct dw8250_data *data)
-{
- struct uart_port *p = &up->port;
-
- dw8250_setup_port(up);
-
- p->iotype = UPIO_MEM32;
- p->serial_in = dw8250_serial_in32;
- p->serial_out = dw8250_serial_out32;
- p->regshift = 2;
-
- up->dma = &data->dma;
-
- up->dma->rxconf.src_maxburst = p->fifosize / 4;
- up->dma->txconf.dst_maxburst = p->fifosize / 4;
-
- up->port.set_termios = dw8250_set_termios;
-
- return 0;
-}
-
-static int dw8250_probe(struct platform_device *pdev)
-{
- struct uart_8250_port uart = {};
- struct resource *regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- int irq = platform_get_irq(pdev, 0);
- struct dw8250_data *data;
- int err;
-
- if (!regs) {
- dev_err(&pdev->dev, "no registers defined\n");
- return -EINVAL;
- }
-
- if (irq < 0) {
- if (irq != -EPROBE_DEFER)
- dev_err(&pdev->dev, "cannot get irq\n");
- return irq;
- }
-
- spin_lock_init(&uart.port.lock);
- uart.port.mapbase = regs->start;
- uart.port.irq = irq;
- uart.port.handle_irq = dw8250_handle_irq;
- uart.port.pm = dw8250_do_pm;
- uart.port.type = PORT_8250;
- uart.port.flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_FIXED_PORT;
- uart.port.dev = &pdev->dev;
-
- uart.port.membase = devm_ioremap(&pdev->dev, regs->start,
- resource_size(regs));
- if (!uart.port.membase)
- return -ENOMEM;
-
- data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
- if (!data)
- return -ENOMEM;
-
- data->usr_reg = DW_UART_USR;
-
/* Always ask for fixed clock rate from a property. */
- device_property_read_u32(&pdev->dev, "clock-frequency",
- &uart.port.uartclk);
+ device_property_read_u32(p->dev, "clock-frequency", &p->uartclk);
/* If there is separate baudclk, get the rate from it. */
data->clk = devm_clk_get(&pdev->dev, "baudclk");
@@ -454,17 +452,17 @@ static int dw8250_probe(struct platform_device *pdev)
dev_warn(&pdev->dev, "could not enable optional baudclk: %d\n",
err);
else
- uart.port.uartclk = clk_get_rate(data->clk);
+ p->uartclk = clk_get_rate(data->clk);
}
/* If no clock rate is defined, fail. */
- if (!uart.port.uartclk) {
+ if (!p->uartclk) {
dev_err(&pdev->dev, "clock rate not defined\n");
return -EINVAL;
}
data->pclk = devm_clk_get(&pdev->dev, "apb_pclk");
- if (IS_ERR(data->clk) && PTR_ERR(data->clk) == -EPROBE_DEFER) {
+ if (IS_ERR(data->pclk) && PTR_ERR(data->pclk) == -EPROBE_DEFER) {
err = -EPROBE_DEFER;
goto err_clk;
}
@@ -484,26 +482,20 @@ static int dw8250_probe(struct platform_device *pdev)
if (!IS_ERR(data->rst))
reset_control_deassert(data->rst);
- data->dma.rx_param = data;
- data->dma.tx_param = data;
- data->dma.fn = dw8250_dma_filter;
+ dw8250_quirks(p, data);
- uart.port.iotype = UPIO_MEM;
- uart.port.serial_in = dw8250_serial_in;
- uart.port.serial_out = dw8250_serial_out;
- uart.port.private_data = data;
+ /* If the Busy Functionality is not implemented, don't handle it */
+ if (data->uart_16550_compatible)
+ p->handle_irq = NULL;
- if (pdev->dev.of_node) {
- err = dw8250_probe_of(&uart.port, data);
- if (err)
- goto err_reset;
- } else if (ACPI_HANDLE(&pdev->dev)) {
- err = dw8250_probe_acpi(&uart, data);
- if (err)
- goto err_reset;
- } else {
- err = -ENODEV;
- goto err_reset;
+ if (!data->skip_autocfg)
+ dw8250_setup_port(p);
+
+ /* If we have a valid fifosize, try hooking up DMA */
+ if (p->fifosize) {
+ data->dma.rxconf.src_maxburst = p->fifosize / 4;
+ data->dma.txconf.dst_maxburst = p->fifosize / 4;
+ uart.dma = &data->dma;
}
data->line = serial8250_register_8250_port(&uart);
@@ -626,6 +618,7 @@ static const struct acpi_device_id dw8250_acpi_match[] = {
{ "8086228A", 0 },
{ "APMC0D08", 0},
{ "AMD0020", 0 },
+ { "AMDI0020", 0 },
{ },
};
MODULE_DEVICE_TABLE(acpi, dw8250_acpi_match);