diff options
author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2012-10-22 14:34:51 +0200 |
---|---|---|
committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2012-10-22 14:34:51 +0200 |
commit | c2fb7916927e989ea424e61ce5fe617e54878827 (patch) | |
tree | 02f9d5482075f8931637d82bb697a6470270136a /drivers/tty/serial/amba-pl011.c | |
parent | 29de6ce574870a0d3fd157afdbf51c0282e2bf63 (diff) | |
parent | 6f0c0580b70c89094b3422ba81118c7b959c7556 (diff) |
Merge tag 'v3.7-rc2' into drm-intel-next-queued
Linux 3.7-rc2
Backmerge to solve two ugly conflicts:
- uapi. We've already added new ioctl definitions for -next. Do I need to say more?
- wc support gtt ptes. We've had to revert this for snb+ for 3.7 and
also fix a few other things in the code. Now we know how to make it
work on snb+, but to avoid losing the other fixes do the backmerge
first before re-enabling wc gtt ptes on snb+.
And a few other minor things, among them git getting confused in
intel_dp.c and seemingly causing a conflict out of nothing ...
Conflicts:
drivers/gpu/drm/i915/i915_reg.h
drivers/gpu/drm/i915/intel_display.c
drivers/gpu/drm/i915/intel_dp.c
drivers/gpu/drm/i915/intel_modes.c
include/drm/i915_drm.h
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'drivers/tty/serial/amba-pl011.c')
-rw-r--r-- | drivers/tty/serial/amba-pl011.c | 177 |
1 files changed, 133 insertions, 44 deletions
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index d3553b5d3fc..d7e1edec50b 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -52,6 +52,8 @@ #include <linux/scatterlist.h> #include <linux/delay.h> #include <linux/types.h> +#include <linux/of.h> +#include <linux/of_device.h> #include <linux/pinctrl/consumer.h> #include <linux/sizes.h> @@ -75,7 +77,6 @@ struct vendor_data { unsigned int lcrh_tx; unsigned int lcrh_rx; bool oversampling; - bool interrupt_may_hang; /* vendor-specific */ bool dma_threshold; bool cts_event_workaround; }; @@ -96,7 +97,6 @@ static struct vendor_data vendor_st = { .lcrh_tx = ST_UART011_LCRH_TX, .lcrh_rx = ST_UART011_LCRH_RX, .oversampling = true, - .interrupt_may_hang = true, .dma_threshold = true, .cts_event_workaround = true, }; @@ -147,7 +147,6 @@ struct uart_amba_port { unsigned int old_cr; /* state during shutdown */ bool autorts; char type[12]; - bool interrupt_may_hang; /* vendor-specific */ #ifdef CONFIG_DMA_ENGINE /* DMA stuff */ bool using_tx_dma; @@ -1215,14 +1214,14 @@ static irqreturn_t pl011_int(int irq, void *dev_id) return IRQ_RETVAL(handled); } -static unsigned int pl01x_tx_empty(struct uart_port *port) +static unsigned int pl011_tx_empty(struct uart_port *port) { struct uart_amba_port *uap = (struct uart_amba_port *)port; unsigned int status = readw(uap->port.membase + UART01x_FR); return status & (UART01x_FR_BUSY|UART01x_FR_TXFF) ? 0 : TIOCSER_TEMT; } -static unsigned int pl01x_get_mctrl(struct uart_port *port) +static unsigned int pl011_get_mctrl(struct uart_port *port) { struct uart_amba_port *uap = (struct uart_amba_port *)port; unsigned int result = 0; @@ -1285,11 +1284,40 @@ static void pl011_break_ctl(struct uart_port *port, int break_state) } #ifdef CONFIG_CONSOLE_POLL -static int pl010_get_poll_char(struct uart_port *port) + +static void pl011_quiesce_irqs(struct uart_port *port) +{ + struct uart_amba_port *uap = (struct uart_amba_port *)port; + unsigned char __iomem *regs = uap->port.membase; + + writew(readw(regs + UART011_MIS), regs + UART011_ICR); + /* + * There is no way to clear TXIM as this is "ready to transmit IRQ", so + * we simply mask it. start_tx() will unmask it. + * + * Note we can race with start_tx(), and if the race happens, the + * polling user might get another interrupt just after we clear it. + * But it should be OK and can happen even w/o the race, e.g. + * controller immediately got some new data and raised the IRQ. + * + * And whoever uses polling routines assumes that it manages the device + * (including tx queue), so we're also fine with start_tx()'s caller + * side. + */ + writew(readw(regs + UART011_IMSC) & ~UART011_TXIM, regs + UART011_IMSC); +} + +static int pl011_get_poll_char(struct uart_port *port) { struct uart_amba_port *uap = (struct uart_amba_port *)port; unsigned int status; + /* + * The caller might need IRQs lowered, e.g. if used with KDB NMI + * debugger. + */ + pl011_quiesce_irqs(port); + status = readw(uap->port.membase + UART01x_FR); if (status & UART01x_FR_RXFE) return NO_POLL_CHAR; @@ -1297,7 +1325,7 @@ static int pl010_get_poll_char(struct uart_port *port) return readw(uap->port.membase + UART01x_DR); } -static void pl010_put_poll_char(struct uart_port *port, +static void pl011_put_poll_char(struct uart_port *port, unsigned char ch) { struct uart_amba_port *uap = (struct uart_amba_port *)port; @@ -1310,10 +1338,9 @@ static void pl010_put_poll_char(struct uart_port *port, #endif /* CONFIG_CONSOLE_POLL */ -static int pl011_startup(struct uart_port *port) +static int pl011_hwinit(struct uart_port *port) { struct uart_amba_port *uap = (struct uart_amba_port *)port; - unsigned int cr; int retval; /* Optionaly enable pins to be muxed in and configured */ @@ -1324,16 +1351,12 @@ static int pl011_startup(struct uart_port *port) "could not set default pins\n"); } - retval = clk_prepare(uap->clk); - if (retval) - goto out; - /* * Try to enable the clock producer. */ - retval = clk_enable(uap->clk); + retval = clk_prepare_enable(uap->clk); if (retval) - goto clk_unprep; + goto out; uap->port.uartclk = clk_get_rate(uap->clk); @@ -1342,6 +1365,37 @@ static int pl011_startup(struct uart_port *port) UART011_RTIS | UART011_RXIS, uap->port.membase + UART011_ICR); /* + * Save interrupts enable mask, and enable RX interrupts in case if + * the interrupt is used for NMI entry. + */ + uap->im = readw(uap->port.membase + UART011_IMSC); + writew(UART011_RTIM | UART011_RXIM, uap->port.membase + UART011_IMSC); + + if (uap->port.dev->platform_data) { + struct amba_pl011_data *plat; + + plat = uap->port.dev->platform_data; + if (plat->init) + plat->init(); + } + return 0; + out: + return retval; +} + +static int pl011_startup(struct uart_port *port) +{ + struct uart_amba_port *uap = (struct uart_amba_port *)port; + unsigned int cr; + int retval; + + retval = pl011_hwinit(port); + if (retval) + goto clk_dis; + + writew(uap->im, uap->port.membase + UART011_IMSC); + + /* * Allocate the IRQ */ retval = request_irq(uap->port.irq, pl011_int, 0, "uart-pl011", uap); @@ -1400,21 +1454,10 @@ static int pl011_startup(struct uart_port *port) writew(uap->im, uap->port.membase + UART011_IMSC); spin_unlock_irq(&uap->port.lock); - if (uap->port.dev->platform_data) { - struct amba_pl011_data *plat; - - plat = uap->port.dev->platform_data; - if (plat->init) - plat->init(); - } - return 0; clk_dis: - clk_disable(uap->clk); - clk_unprep: - clk_unprepare(uap->clk); - out: + clk_disable_unprepare(uap->clk); return retval; } @@ -1473,8 +1516,7 @@ static void pl011_shutdown(struct uart_port *port) /* * Shut down the clock producer */ - clk_disable(uap->clk); - clk_unprepare(uap->clk); + clk_disable_unprepare(uap->clk); /* Optionally let pins go into sleep states */ if (!IS_ERR(uap->pins_sleep)) { retval = pinctrl_select_state(uap->pinctrl, uap->pins_sleep); @@ -1603,13 +1645,26 @@ pl011_set_termios(struct uart_port *port, struct ktermios *termios, old_cr &= ~ST_UART011_CR_OVSFACT; } + /* + * Workaround for the ST Micro oversampling variants to + * increase the bitrate slightly, by lowering the divisor, + * to avoid delayed sampling of start bit at high speeds, + * else we see data corruption. + */ + if (uap->vendor->oversampling) { + if ((baud >= 3000000) && (baud < 3250000) && (quot > 1)) + quot -= 1; + else if ((baud > 3250000) && (quot > 2)) + quot -= 2; + } /* Set baud rate */ writew(quot & 0x3f, port->membase + UART011_FBRD); writew(quot >> 6, port->membase + UART011_IBRD); /* * ----------v----------v----------v----------v----- - * NOTE: MUST BE WRITTEN AFTER UARTLCR_M & UARTLCR_L + * NOTE: lcrh_tx and lcrh_rx MUST BE WRITTEN AFTER + * UART011_FBRD & UART011_IBRD. * ----------^----------^----------^----------^----- */ writew(lcr_h, port->membase + uap->lcrh_rx); @@ -1637,7 +1692,7 @@ static const char *pl011_type(struct uart_port *port) /* * Release the memory region(s) being used by 'port' */ -static void pl010_release_port(struct uart_port *port) +static void pl011_release_port(struct uart_port *port) { release_mem_region(port->mapbase, SZ_4K); } @@ -1645,7 +1700,7 @@ static void pl010_release_port(struct uart_port *port) /* * Request the memory region(s) being used by 'port' */ -static int pl010_request_port(struct uart_port *port) +static int pl011_request_port(struct uart_port *port) { return request_mem_region(port->mapbase, SZ_4K, "uart-pl011") != NULL ? 0 : -EBUSY; @@ -1654,18 +1709,18 @@ static int pl010_request_port(struct uart_port *port) /* * Configure/autoconfigure the port. */ -static void pl010_config_port(struct uart_port *port, int flags) +static void pl011_config_port(struct uart_port *port, int flags) { if (flags & UART_CONFIG_TYPE) { port->type = PORT_AMBA; - pl010_request_port(port); + pl011_request_port(port); } } /* * verify the new serial_struct (for TIOCSSERIAL). */ -static int pl010_verify_port(struct uart_port *port, struct serial_struct *ser) +static int pl011_verify_port(struct uart_port *port, struct serial_struct *ser) { int ret = 0; if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA) @@ -1678,9 +1733,9 @@ static int pl010_verify_port(struct uart_port *port, struct serial_struct *ser) } static struct uart_ops amba_pl011_pops = { - .tx_empty = pl01x_tx_empty, + .tx_empty = pl011_tx_empty, .set_mctrl = pl011_set_mctrl, - .get_mctrl = pl01x_get_mctrl, + .get_mctrl = pl011_get_mctrl, .stop_tx = pl011_stop_tx, .start_tx = pl011_start_tx, .stop_rx = pl011_stop_rx, @@ -1691,13 +1746,14 @@ static struct uart_ops amba_pl011_pops = { .flush_buffer = pl011_dma_flush_buffer, .set_termios = pl011_set_termios, .type = pl011_type, - .release_port = pl010_release_port, - .request_port = pl010_request_port, - .config_port = pl010_config_port, - .verify_port = pl010_verify_port, + .release_port = pl011_release_port, + .request_port = pl011_request_port, + .config_port = pl011_config_port, + .verify_port = pl011_verify_port, #ifdef CONFIG_CONSOLE_POLL - .poll_get_char = pl010_get_poll_char, - .poll_put_char = pl010_put_poll_char, + .poll_init = pl011_hwinit, + .poll_get_char = pl011_get_poll_char, + .poll_put_char = pl011_put_poll_char, #endif }; @@ -1869,6 +1925,38 @@ static struct uart_driver amba_reg = { .cons = AMBA_CONSOLE, }; +static int pl011_probe_dt_alias(int index, struct device *dev) +{ + struct device_node *np; + static bool seen_dev_with_alias = false; + static bool seen_dev_without_alias = false; + int ret = index; + + if (!IS_ENABLED(CONFIG_OF)) + return ret; + + np = dev->of_node; + if (!np) + return ret; + + ret = of_alias_get_id(np, "serial"); + if (IS_ERR_VALUE(ret)) { + seen_dev_without_alias = true; + ret = index; + } else { + seen_dev_with_alias = true; + if (ret >= ARRAY_SIZE(amba_ports) || amba_ports[ret] != NULL) { + dev_warn(dev, "requested serial port %d not available.\n", ret); + ret = index; + } + } + + if (seen_dev_with_alias && seen_dev_without_alias) + dev_warn(dev, "aliased and non-aliased serial devices found in device tree. Serial port enumeration may be unpredictable.\n"); + + return ret; +} + static int pl011_probe(struct amba_device *dev, const struct amba_id *id) { struct uart_amba_port *uap; @@ -1891,6 +1979,8 @@ static int pl011_probe(struct amba_device *dev, const struct amba_id *id) goto out; } + i = pl011_probe_dt_alias(i, &dev->dev); + base = ioremap(dev->res.start, resource_size(&dev->res)); if (!base) { ret = -ENOMEM; @@ -1923,7 +2013,6 @@ static int pl011_probe(struct amba_device *dev, const struct amba_id *id) uap->lcrh_tx = vendor->lcrh_tx; uap->old_cr = 0; uap->fifosize = vendor->fifosize; - uap->interrupt_may_hang = vendor->interrupt_may_hang; uap->port.dev = &dev->dev; uap->port.mapbase = dev->res.start; uap->port.membase = base; |