From 09498087f922bb623b66db9e89c6fd11a3799867 Mon Sep 17 00:00:00 2001 From: Heiko Stuebner Date: Thu, 9 Mar 2017 07:41:16 +0100 Subject: serial: 8250_dw: Honor clk_round_rate errors in dw8250_set_termios clk_round_rate returns a signed long and may possibly return errors in it, for example if there is no possible rate. Till now dw8250_set_termios ignored any error, the signednes and would just use the value as input to clk_set_rate. This of course falls apart if there is an actual error, so check for errors and only try to set a rate if the value is actually valid. This turned up on some Rockchip platforms after commit 6a171b299379 ("serial: 8250_dw: Allow hardware flow control to be used") enabled set_termios callback in all cases, not only ACPI. Fixes: 6a171b299379 ("serial: 8250_dw: Allow hardware flow control to be used") Signed-off-by: Heiko Stuebner Reviewed-by: Andy Shevchenko Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250_dw.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'drivers/tty') diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c index 6ee55a2..223ac23 100644 --- a/drivers/tty/serial/8250/8250_dw.c +++ b/drivers/tty/serial/8250/8250_dw.c @@ -257,7 +257,7 @@ static void dw8250_set_termios(struct uart_port *p, struct ktermios *termios, { unsigned int baud = tty_termios_baud_rate(termios); struct dw8250_data *d = p->private_data; - unsigned int rate; + long rate; int ret; if (IS_ERR(d->clk) || !old) @@ -265,7 +265,10 @@ static void dw8250_set_termios(struct uart_port *p, struct ktermios *termios, clk_disable_unprepare(d->clk); rate = clk_round_rate(d->clk, baud * 16); - ret = clk_set_rate(d->clk, rate); + if (rate < 0) + ret = rate; + else + ret = clk_set_rate(d->clk, rate); clk_prepare_enable(d->clk); if (!ret) -- cgit v1.1 From b15bfbe6427712d1b992bf806a6df9c05002a0a4 Mon Sep 17 00:00:00 2001 From: James Hogan Date: Sat, 4 Mar 2017 13:09:58 +0000 Subject: serial: 8250_dw: Fix breakage when HAVE_CLK=n Commit 6a171b299379 ("serial: 8250_dw: Allow hardware flow control to be used") recently broke the 8250_dw driver on platforms which don't select HAVE_CLK, as dw8250_set_termios() gets confused by the behaviour of the fallback HAVE_CLK=n clock API in linux/clk.h which pretends everything is fine but returns (valid) NULL clocks and 0 HZ clock rates. That 0 rate is written into the uartclk resulting in a crash at boot, e.g. on Cavium Octeon III based UTM-8 we get something like this: 1180000000800.serial: ttyS0 at MMIO 0x1180000000800 (irq = 41, base_baud = 25000000) is a OCTEON ------------[ cut here ]------------ WARNING: CPU: 2 PID: 1 at drivers/tty/serial/serial_core.c:441 uart_get_baud_rate+0xfc/0x1f0 ... Call Trace: ... [] uart_get_baud_rate+0xfc/0x1f0 [] serial8250_do_set_termios+0xb0/0x440 [] uart_set_options+0xe8/0x190 [] serial8250_console_setup+0x84/0x158 [] univ8250_console_setup+0x54/0x70 [] register_console+0x1c8/0x418 [] uart_add_one_port+0x434/0x4b0 [] serial8250_register_8250_port+0x2d8/0x440 [] dw8250_probe+0x388/0x5e8 ... The clock API is defined such that NULL is a valid clock handle so it wouldn't be right to check explicitly for NULL. Instead treat a clk_round_rate() return value of 0 as an error which prevents uartclk being overwritten. Fixes: 6a171b299379 ("serial: 8250_dw: Allow hardware flow control to be used") Signed-off-by: James Hogan Cc: Kefeng Wang Cc: David Daney Cc: Russell King Cc: linux-serial@vger.kernel.org Cc: linux-clk@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: bcm-kernel-feedback-list@broadcom.com Reviewed-by: Andy Shevchenko Reviewed-by: Jason Uy Reviewed-by: Heiko Stuebner Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/8250_dw.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/tty') diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c index 223ac23..e65808c 100644 --- a/drivers/tty/serial/8250/8250_dw.c +++ b/drivers/tty/serial/8250/8250_dw.c @@ -267,6 +267,8 @@ static void dw8250_set_termios(struct uart_port *p, struct ktermios *termios, rate = clk_round_rate(d->clk, baud * 16); if (rate < 0) ret = rate; + else if (rate == 0) + ret = -ENOENT; else ret = clk_set_rate(d->clk, rate); clk_prepare_enable(d->clk); -- cgit v1.1 From b767ad726c2aa6219318bf0da83fbe690e653d9a Mon Sep 17 00:00:00 2001 From: Aleksey Makarov Date: Wed, 1 Mar 2017 18:23:02 +0300 Subject: Revert "tty: serial: pl011: add ttyAMA for matching pl011 console" The original patch makes the condition always true, so it is wrong. It masks (but not fixes) the bug described in the commit message but introduces a regression (no console is selected by SPCR) in regular (no 'console=ttyAMA') case. s/||/&&/ would not fix the problem as the root cause was identified incorrectly. This reverts commit aea9a80ba98a0c9b4de88850260e9fbdcc98360b. Signed-off-by: Aleksey Makarov Signed-off-by: Greg Kroah-Hartman Acked-by: Sudeep Holla Tested-by: Jayachandran C Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/amba-pl011.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/tty') diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index 8789ea4..56f92d7 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -2373,7 +2373,7 @@ static int __init pl011_console_match(struct console *co, char *name, int idx, if (strcmp(name, "qdf2400_e44") == 0) { pr_info_once("UART: Working around QDF2400 SoC erratum 44"); qdf2400_e44_present = true; - } else if (strcmp(name, "pl011") != 0 || strcmp(name, "ttyAMA") != 0) { + } else if (strcmp(name, "pl011") != 0) { return -ENODEV; } -- cgit v1.1 From 5362544bebe85071188dd9e479b5a5040841c895 Mon Sep 17 00:00:00 2001 From: Dmitry Vyukov Date: Sat, 4 Mar 2017 14:55:19 +0100 Subject: tty: don't panic on OOM in tty_set_ldisc() If tty_ldisc_open() fails in tty_set_ldisc(), it tries to go back to the old discipline or N_TTY. But that can fail as well, in such case it panics. This is not a graceful way to handle OOM. Leave ldisc==NULL if all attempts fail instead. Also use existing tty_ldisc_reinit() helper function instead of tty_ldisc_restore(). Also don't WARN/BUG in tty_ldisc_reinit() if N_TTY fails, which would have the same net effect of bringing kernel down on OOM. Instead print a single line message about what has happened. Signed-off-by: Dmitry Vyukov Cc: syzkaller@googlegroups.com Cc: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman Cc: Jiri Slaby Cc: Peter Hurley Cc: One Thousand Gnomes Signed-off-by: Greg Kroah-Hartman --- drivers/tty/tty_ldisc.c | 85 ++++++++++--------------------------------------- 1 file changed, 16 insertions(+), 69 deletions(-) (limited to 'drivers/tty') diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c index 68947f6..c3956ca 100644 --- a/drivers/tty/tty_ldisc.c +++ b/drivers/tty/tty_ldisc.c @@ -489,41 +489,6 @@ static void tty_ldisc_close(struct tty_struct *tty, struct tty_ldisc *ld) } /** - * tty_ldisc_restore - helper for tty ldisc change - * @tty: tty to recover - * @old: previous ldisc - * - * Restore the previous line discipline or N_TTY when a line discipline - * change fails due to an open error - */ - -static void tty_ldisc_restore(struct tty_struct *tty, struct tty_ldisc *old) -{ - struct tty_ldisc *new_ldisc; - int r; - - /* There is an outstanding reference here so this is safe */ - old = tty_ldisc_get(tty, old->ops->num); - WARN_ON(IS_ERR(old)); - tty->ldisc = old; - tty_set_termios_ldisc(tty, old->ops->num); - if (tty_ldisc_open(tty, old) < 0) { - tty_ldisc_put(old); - /* This driver is always present */ - new_ldisc = tty_ldisc_get(tty, N_TTY); - if (IS_ERR(new_ldisc)) - panic("n_tty: get"); - tty->ldisc = new_ldisc; - tty_set_termios_ldisc(tty, N_TTY); - r = tty_ldisc_open(tty, new_ldisc); - if (r < 0) - panic("Couldn't open N_TTY ldisc for " - "%s --- error %d.", - tty_name(tty), r); - } -} - -/** * tty_set_ldisc - set line discipline * @tty: the terminal to set * @ldisc: the line discipline @@ -536,12 +501,7 @@ static void tty_ldisc_restore(struct tty_struct *tty, struct tty_ldisc *old) int tty_set_ldisc(struct tty_struct *tty, int disc) { - int retval; - struct tty_ldisc *old_ldisc, *new_ldisc; - - new_ldisc = tty_ldisc_get(tty, disc); - if (IS_ERR(new_ldisc)) - return PTR_ERR(new_ldisc); + int retval, old_disc; tty_lock(tty); retval = tty_ldisc_lock(tty, 5 * HZ); @@ -554,7 +514,8 @@ int tty_set_ldisc(struct tty_struct *tty, int disc) } /* Check the no-op case */ - if (tty->ldisc->ops->num == disc) + old_disc = tty->ldisc->ops->num; + if (old_disc == disc) goto out; if (test_bit(TTY_HUPPED, &tty->flags)) { @@ -563,34 +524,25 @@ int tty_set_ldisc(struct tty_struct *tty, int disc) goto out; } - old_ldisc = tty->ldisc; - - /* Shutdown the old discipline. */ - tty_ldisc_close(tty, old_ldisc); - - /* Now set up the new line discipline. */ - tty->ldisc = new_ldisc; - tty_set_termios_ldisc(tty, disc); - - retval = tty_ldisc_open(tty, new_ldisc); + retval = tty_ldisc_reinit(tty, disc); if (retval < 0) { /* Back to the old one or N_TTY if we can't */ - tty_ldisc_put(new_ldisc); - tty_ldisc_restore(tty, old_ldisc); + if (tty_ldisc_reinit(tty, old_disc) < 0) { + pr_err("tty: TIOCSETD failed, reinitializing N_TTY\n"); + if (tty_ldisc_reinit(tty, N_TTY) < 0) { + /* At this point we have tty->ldisc == NULL. */ + pr_err("tty: reinitializing N_TTY failed\n"); + } + } } - if (tty->ldisc->ops->num != old_ldisc->ops->num && tty->ops->set_ldisc) { + if (tty->ldisc && tty->ldisc->ops->num != old_disc && + tty->ops->set_ldisc) { down_read(&tty->termios_rwsem); tty->ops->set_ldisc(tty); up_read(&tty->termios_rwsem); } - /* At this point we hold a reference to the new ldisc and a - reference to the old ldisc, or we hold two references to - the old ldisc (if it was restored as part of error cleanup - above). In either case, releasing a single reference from - the old ldisc is correct. */ - new_ldisc = old_ldisc; out: tty_ldisc_unlock(tty); @@ -598,7 +550,6 @@ out: already running */ tty_buffer_restart_work(tty->port); err: - tty_ldisc_put(new_ldisc); /* drop the extra reference */ tty_unlock(tty); return retval; } @@ -659,10 +610,8 @@ int tty_ldisc_reinit(struct tty_struct *tty, int disc) int retval; ld = tty_ldisc_get(tty, disc); - if (IS_ERR(ld)) { - BUG_ON(disc == N_TTY); + if (IS_ERR(ld)) return PTR_ERR(ld); - } if (tty->ldisc) { tty_ldisc_close(tty, tty->ldisc); @@ -674,10 +623,8 @@ int tty_ldisc_reinit(struct tty_struct *tty, int disc) tty_set_termios_ldisc(tty, disc); retval = tty_ldisc_open(tty, tty->ldisc); if (retval) { - if (!WARN_ON(disc == N_TTY)) { - tty_ldisc_put(tty->ldisc); - tty->ldisc = NULL; - } + tty_ldisc_put(tty->ldisc); + tty->ldisc = NULL; } return retval; } -- cgit v1.1 From a4a3e061149f09c075f108b6f1cf04d9739a6bc2 Mon Sep 17 00:00:00 2001 From: Dmitry Vyukov Date: Sat, 4 Mar 2017 13:46:12 +0100 Subject: tty: fix data race in tty_ldisc_ref_wait() tty_ldisc_ref_wait() checks tty->ldisc under tty->ldisc_sem. But if ldisc==NULL it releases them sem and reloads tty->ldisc without holding the sem. This is wrong and can lead to returning non-NULL ldisc without protection. Don't reload tty->ldisc second time. Signed-off-by: Dmitry Vyukov Cc: syzkaller@googlegroups.com Cc: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman Cc: Jiri Slaby Cc: Peter Hurley Cc: One Thousand Gnomes Signed-off-by: Greg Kroah-Hartman --- drivers/tty/tty_ldisc.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'drivers/tty') diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c index c3956ca..b0500a0 100644 --- a/drivers/tty/tty_ldisc.c +++ b/drivers/tty/tty_ldisc.c @@ -271,10 +271,13 @@ const struct file_operations tty_ldiscs_proc_fops = { struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *tty) { + struct tty_ldisc *ld; + ldsem_down_read(&tty->ldisc_sem, MAX_SCHEDULE_TIMEOUT); - if (!tty->ldisc) + ld = tty->ldisc; + if (!ld) ldsem_up_read(&tty->ldisc_sem); - return tty->ldisc; + return ld; } EXPORT_SYMBOL_GPL(tty_ldisc_ref_wait); -- cgit v1.1 From 658b299580da2830a69eea44a8b6da1c2579a32e Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Tue, 28 Mar 2017 09:53:00 +0200 Subject: sched/headers: Remove duplicate #include line Vito Caputo reported that the sched.h split-up series introduced a duplicate #include line in drivers/tty/vt/keyboard.c. Remove it. Reported-by: Vito Caputo Cc: Greg Kroah-Hartman Cc: Jiri Slaby Cc: Alan Cox Cc: Greg Kroah-Hartman Cc: Linus Torvalds Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar --- drivers/tty/vt/keyboard.c | 1 - 1 file changed, 1 deletion(-) (limited to 'drivers/tty') diff --git a/drivers/tty/vt/keyboard.c b/drivers/tty/vt/keyboard.c index c5f0fc9..8af8d95 100644 --- a/drivers/tty/vt/keyboard.c +++ b/drivers/tty/vt/keyboard.c @@ -28,7 +28,6 @@ #include #include #include -#include #include #include #include -- cgit v1.1 From a6040bc610554c66088fda3608ae5d6307c548e4 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= Date: Mon, 20 Mar 2017 10:05:38 +0100 Subject: serial: mxs-auart: Fix baudrate calculation MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The reference manual for the i.MX28 recommends to calculate the divisor as divisor = (UARTCLK * 32) / baud rate, rounded to the nearest integer , so let's do this. For a typical setup of UARTCLK = 24 MHz and baud rate = 115200 this changes the divisor from 6666 to 6667 and so the actual baud rate improves from 115211.521 Bd (error ≅ 0.01 %) to 115194.240 Bd (error ≅ 0.005 %). Signed-off-by: Uwe Kleine-König Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/mxs-auart.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/tty') diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c index 6989b227d..be94246 100644 --- a/drivers/tty/serial/mxs-auart.c +++ b/drivers/tty/serial/mxs-auart.c @@ -1088,7 +1088,7 @@ static void mxs_auart_settermios(struct uart_port *u, AUART_LINECTRL_BAUD_DIV_MAX); baud_max = u->uartclk * 32 / AUART_LINECTRL_BAUD_DIV_MIN; baud = uart_get_baud_rate(u, termios, old, baud_min, baud_max); - div = u->uartclk * 32 / baud; + div = DIV_ROUND_CLOSEST(u->uartclk * 32, baud); } ctrl |= AUART_LINECTRL_BAUD_DIVFRAC(div & 0x3F); -- cgit v1.1 From 31ca2c63fdc0aee725cbd4f207c1256f5deaabde Mon Sep 17 00:00:00 2001 From: Richard Genoud Date: Mon, 20 Mar 2017 11:52:41 +0100 Subject: tty/serial: atmel: fix race condition (TX+DMA) If uart_flush_buffer() is called between atmel_tx_dma() and atmel_complete_tx_dma(), the circular buffer has been cleared, but not atmel_port->tx_len. That leads to a circular buffer overflow (dumping (UART_XMIT_SIZE - atmel_port->tx_len) bytes). Tested-by: Nicolas Ferre Signed-off-by: Richard Genoud Cc: stable # 3.12+ Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/atmel_serial.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'drivers/tty') diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c index dcebb28..5f64451 100644 --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -1951,6 +1951,11 @@ static void atmel_flush_buffer(struct uart_port *port) atmel_uart_writel(port, ATMEL_PDC_TCR, 0); atmel_port->pdc_tx.ofs = 0; } + /* + * in uart_flush_buffer(), the xmit circular buffer has just + * been cleared, so we have to reset tx_len accordingly. + */ + atmel_port->tx_len = 0; } /* -- cgit v1.1 From 497e1e16f45c70574dc9922c7f75c642c2162119 Mon Sep 17 00:00:00 2001 From: Nicolas Ferre Date: Mon, 20 Mar 2017 16:38:57 +0100 Subject: tty/serial: atmel: fix TX path in atmel_console_write() A side effect of 89d8232411a8 ("tty/serial: atmel_serial: BUG: stop DMA from transmitting in stop_tx") is that the console can be called with TX path disabled. Then the system would hang trying to push charecters out in atmel_console_putchar(). Signed-off-by: Nicolas Ferre Fixes: 89d8232411a8 ("tty/serial: atmel_serial: BUG: stop DMA from transmitting in stop_tx") Cc: stable #4.4+ Acked-by: Richard Genoud Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/atmel_serial.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/tty') diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c index 5f64451..1f50a83 100644 --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -2488,6 +2488,9 @@ static void atmel_console_write(struct console *co, const char *s, u_int count) pdc_tx = atmel_uart_readl(port, ATMEL_PDC_PTSR) & ATMEL_PDC_TXTEN; atmel_uart_writel(port, ATMEL_PDC_PTCR, ATMEL_PDC_TXTDIS); + /* Make sure that tx path is actually able to send characters */ + atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_TXEN); + uart_console_write(port, s, count, atmel_console_putchar); /* -- cgit v1.1 From 49e1590c2ead870f4ae5568816241c4cb9bc1606 Mon Sep 17 00:00:00 2001 From: Paul Gortmaker Date: Mon, 27 Mar 2017 19:39:10 -0400 Subject: serial: 8250_EXAR: fix duplicate Kconfig text and add missing help text In commit d0aeaa83f0b0f7a92615bbdd6b1f96812f7dcfd2 ("serial: exar: split out the exar code from 8250_pci") the exar driver got its own Kconfig. However the text for the new option was never changed from the original 8250_PCI text, and hence it appears confusing when you get asked the same question twice: 8250/16550 PCI device support (SERIAL_8250_PCI) [Y/n/m/?] (NEW) 8250/16550 PCI device support (SERIAL_8250_EXAR) [Y/n/m] (NEW) Adding to the confusion, is that there is no help text for this new option to indicate it is specific to a certain family of cards. Fix both issues at the same time, as well as the space vs. tab issues introduced in the same commit. Fixes: d0aeaa83f0b0 ("serial: exar: split out the exar code from 8250_pci") Cc: Jiri Slaby Cc: linux-serial@vger.kernel.org Signed-off-by: Paul Gortmaker Acked-by: Sudip Mukherjee Reviewed-by: Andy Shevchenko Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250/Kconfig | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'drivers/tty') diff --git a/drivers/tty/serial/8250/Kconfig b/drivers/tty/serial/8250/Kconfig index a65fb81..0e3f529 100644 --- a/drivers/tty/serial/8250/Kconfig +++ b/drivers/tty/serial/8250/Kconfig @@ -128,9 +128,13 @@ config SERIAL_8250_PCI by the parport_serial driver, enabled with CONFIG_PARPORT_SERIAL. config SERIAL_8250_EXAR - tristate "8250/16550 PCI device support" - depends on SERIAL_8250_PCI + tristate "8250/16550 Exar/Commtech PCI/PCIe device support" + depends on SERIAL_8250_PCI default SERIAL_8250 + help + This builds support for XR17C1xx, XR17V3xx and some Commtech + 422x PCIe serial cards that are not covered by the more generic + SERIAL_8250_PCI option. config SERIAL_8250_HP300 tristate -- cgit v1.1 From e53e597fd4c4a0b6ae58e57d76a240927fd17eaa Mon Sep 17 00:00:00 2001 From: Timur Tabi Date: Fri, 31 Mar 2017 17:05:02 -0500 Subject: tty: pl011: fix earlycon work-around for QDF2400 erratum 44 The work-around for the Qualcomm Datacenter Technologies QDF2400 erratum 44 sets the "qdf2400_e44_present" global variable if the work-around is needed. However, this check does not happen until after earlycon is initialized, which means the work-around is not used, and the console hangs as soon as it displays one character. Fixes: d8a4995bcea1 ("tty: pl011: Work around QDF2400 E44 stuck BUSY bit") Signed-off-by: Timur Tabi Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/amba-pl011.c | 23 +++++++++++++++++++++-- 1 file changed, 21 insertions(+), 2 deletions(-) (limited to 'drivers/tty') diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index 56f92d7..b0a3777 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -2452,18 +2452,37 @@ static void pl011_early_write(struct console *con, const char *s, unsigned n) uart_console_write(&dev->port, s, n, pl011_putc); } +/* + * On non-ACPI systems, earlycon is enabled by specifying + * "earlycon=pl011,
" on the kernel command line. + * + * On ACPI ARM64 systems, an "early" console is enabled via the SPCR table, + * by specifying only "earlycon" on the command line. Because it requires + * SPCR, the console starts after ACPI is parsed, which is later than a + * traditional early console. + * + * To get the traditional early console that starts before ACPI is parsed, + * specify the full "earlycon=pl011,
" option. + */ static int __init pl011_early_console_setup(struct earlycon_device *device, const char *opt) { if (!device->port.membase) return -ENODEV; - device->con->write = qdf2400_e44_present ? - qdf2400_e44_early_write : pl011_early_write; + /* On QDF2400 SOCs affected by Erratum 44, the "qdf2400_e44" must + * also be specified, e.g. "earlycon=pl011,
,qdf2400_e44". + */ + if (!strcmp(device->options, "qdf2400_e44")) + device->con->write = qdf2400_e44_early_write; + else + device->con->write = pl011_early_write; + return 0; } OF_EARLYCON_DECLARE(pl011, "arm,pl011", pl011_early_console_setup); OF_EARLYCON_DECLARE(pl011, "arm,sbsa-uart", pl011_early_console_setup); +EARLYCON_DECLARE(qdf2400_e44, pl011_early_console_setup); #else #define AMBA_CONSOLE NULL -- cgit v1.1