From eb7073db1076777496495483854993165e14790f Mon Sep 17 00:00:00 2001 From: Tomoya MORINAGA Date: Thu, 2 Jun 2011 11:31:29 +0900 Subject: [PATCH 01/12] 8250_pci: add -ENODEV code for Intel EG20T PCH Intel EG20T PCH has UART device which is compatible with 8250. Currently, with general configuration, the PCH UART driver is not loaded but 8250 standard driver is loaded. Therefore, in case of using PCH UART driver, need to disable 8250 pci function. However, this procedure is not best solution. This patch, in 8250_pci, if the device is the PCH or the family IOH, '-ENODEV' is returned. As a result, disabling 8250-pci processing becomes unnecessary. Signed-off-by: Tomoya MORINAGA Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250_pci.c | 59 +++++++++++++++++++++++++++++++++++ 1 file changed, 59 insertions(+) diff --git a/drivers/tty/serial/8250_pci.c b/drivers/tty/serial/8250_pci.c index 4b4968a294b2..d7dc513451a6 100644 --- a/drivers/tty/serial/8250_pci.c +++ b/drivers/tty/serial/8250_pci.c @@ -994,6 +994,15 @@ static int skip_tx_en_setup(struct serial_private *priv, return pci_default_setup(priv, board, port, idx); } +static int pci_eg20t_init(struct pci_dev *dev) +{ +#if defined(CONFIG_SERIAL_PCH_UART) || defined(CONFIG_SERIAL_PCH_UART_MODULE) + return -ENODEV; +#else + return 0; +#endif +} + /* This should be in linux/pci_ids.h */ #define PCI_VENDOR_ID_SBSMODULARIO 0x124B #define PCI_SUBVENDOR_ID_SBSMODULARIO 0x124B @@ -1446,6 +1455,56 @@ static struct pci_serial_quirk pci_serial_quirks[] __refdata = { .init = pci_oxsemi_tornado_init, .setup = pci_default_setup, }, + { + .vendor = PCI_VENDOR_ID_INTEL, + .device = 0x8811, + .init = pci_eg20t_init, + }, + { + .vendor = PCI_VENDOR_ID_INTEL, + .device = 0x8812, + .init = pci_eg20t_init, + }, + { + .vendor = PCI_VENDOR_ID_INTEL, + .device = 0x8813, + .init = pci_eg20t_init, + }, + { + .vendor = PCI_VENDOR_ID_INTEL, + .device = 0x8814, + .init = pci_eg20t_init, + }, + { + .vendor = 0x10DB, + .device = 0x8027, + .init = pci_eg20t_init, + }, + { + .vendor = 0x10DB, + .device = 0x8028, + .init = pci_eg20t_init, + }, + { + .vendor = 0x10DB, + .device = 0x8029, + .init = pci_eg20t_init, + }, + { + .vendor = 0x10DB, + .device = 0x800C, + .init = pci_eg20t_init, + }, + { + .vendor = 0x10DB, + .device = 0x800D, + .init = pci_eg20t_init, + }, + { + .vendor = 0x10DB, + .device = 0x800D, + .init = pci_eg20t_init, + }, /* * Cronyx Omega PCI (PLX-chip based) */ From af99d6f0037d970084b03d9690f50e34d6f70dae Mon Sep 17 00:00:00 2001 From: Lennart Sorensen Date: Wed, 1 Jun 2011 14:38:41 -0400 Subject: [PATCH 02/12] serial: ioremap warning fix for jsm driver. I saw a warning about ioremap from the jsm driver on a system which looked like this: resource map sanity check conflict: 0xe0200800 0xe02017ff 0xe0200800 0xe0200fff 0000:01:08.0 Turns out the warning is valid. The jsm driver has been asking to ioremap 0x1000 forever, but in fact only 8 port chips have 0x1000 bytes of memory. 4 port chips have 0x800 and 2 port chips have 0x400 according to the data sheet. It makes more sense to map the size of the region rather than a hard coded value. If you happen to have the region legitimately mapped to a base address that is not 4K aligned, ioremap complains otherwise. Signed-off-by: Len Sorensen Acked-by: Alan Cox Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/jsm/jsm_driver.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/tty/serial/jsm/jsm_driver.c b/drivers/tty/serial/jsm/jsm_driver.c index 18f548449c63..96da17868cf3 100644 --- a/drivers/tty/serial/jsm/jsm_driver.c +++ b/drivers/tty/serial/jsm/jsm_driver.c @@ -125,7 +125,7 @@ static int __devinit jsm_probe_one(struct pci_dev *pdev, const struct pci_device brd->bd_uart_offset = 0x200; brd->bd_dividend = 921600; - brd->re_map_membase = ioremap(brd->membase, 0x1000); + brd->re_map_membase = ioremap(brd->membase, pci_resource_len(pdev, 0)); if (!brd->re_map_membase) { dev_err(&pdev->dev, "card has no PCI Memory resources, " From 470f22975448a65a1084a6f0721fa5df15323f02 Mon Sep 17 00:00:00 2001 From: Boojin Kim Date: Fri, 27 May 2011 19:04:03 -0700 Subject: [PATCH 03/12] ARM: SAMSUNG: serial: Fix on handling of one clock source for UART This patch fixes the way of comparison for handling of two or more clock sources for UART. For example, if just only one clock source is defined even though there are two clock sources for UART, the serial driver does not set proper clock up. Of course, it is problem. So this patch changes the condition of comparison to avoid useless setup clock and adds a flag 'NO_NEED_CHECK_CLKSRC' which means selection of source clock is not required. In addition, since the Exynos4210 has only one clock source for UART this patch adds the flag into its common_init_uarts(). Signed-off-by: Boojin Kim Signed-off-by: Kukjin Kim Cc: stable Signed-off-by: Greg Kroah-Hartman --- arch/arm/mach-exynos4/init.c | 1 + arch/arm/plat-samsung/include/plat/regs-serial.h | 2 ++ drivers/tty/serial/s5pv210.c | 4 ++-- 3 files changed, 5 insertions(+), 2 deletions(-) diff --git a/arch/arm/mach-exynos4/init.c b/arch/arm/mach-exynos4/init.c index cf91f50e43ab..a8a83e3881a4 100644 --- a/arch/arm/mach-exynos4/init.c +++ b/arch/arm/mach-exynos4/init.c @@ -35,6 +35,7 @@ void __init exynos4_common_init_uarts(struct s3c2410_uartcfg *cfg, int no) tcfg->clocks = exynos4_serial_clocks; tcfg->clocks_size = ARRAY_SIZE(exynos4_serial_clocks); } + tcfg->flags |= NO_NEED_CHECK_CLKSRC; } s3c24xx_init_uartdevs("s5pv210-uart", s5p_uart_resources, cfg, no); diff --git a/arch/arm/plat-samsung/include/plat/regs-serial.h b/arch/arm/plat-samsung/include/plat/regs-serial.h index c151c5f94a87..116edfe120b9 100644 --- a/arch/arm/plat-samsung/include/plat/regs-serial.h +++ b/arch/arm/plat-samsung/include/plat/regs-serial.h @@ -224,6 +224,8 @@ #define S5PV210_UFSTAT_RXMASK (255<<0) #define S5PV210_UFSTAT_RXSHIFT (0) +#define NO_NEED_CHECK_CLKSRC 1 + #ifndef __ASSEMBLY__ /* struct s3c24xx_uart_clksrc diff --git a/drivers/tty/serial/s5pv210.c b/drivers/tty/serial/s5pv210.c index fb2619f93d84..dd194dc80ee9 100644 --- a/drivers/tty/serial/s5pv210.c +++ b/drivers/tty/serial/s5pv210.c @@ -30,7 +30,7 @@ static int s5pv210_serial_setsource(struct uart_port *port, struct s3c2410_uartcfg *cfg = port->dev->platform_data; unsigned long ucon = rd_regl(port, S3C2410_UCON); - if ((cfg->clocks_size) == 1) + if (cfg->flags & NO_NEED_CHECK_CLKSRC) return 0; if (strcmp(clk->name, "pclk") == 0) @@ -55,7 +55,7 @@ static int s5pv210_serial_getsource(struct uart_port *port, clk->divisor = 1; - if ((cfg->clocks_size) == 1) + if (cfg->flags & NO_NEED_CHECK_CLKSRC) return 0; switch (ucon & S5PV210_UCON_CLKMASK) { From 1798ca13bfae8cc7c0ef82c034c3c4951ecaeb88 Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Tue, 24 May 2011 12:35:48 +0100 Subject: [PATCH 04/12] 8250_pci: Fix missing const from merges Signed-off-by: Alan Cox Signed-off-by: Antony Pavlov Signed-off-by: Borislav Petkov Signed-off-by: Vasily Averin Signed-off-by: Guenter Roeck Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250_pci.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/tty/serial/8250_pci.c b/drivers/tty/serial/8250_pci.c index d7dc513451a6..f41b4259ecdd 100644 --- a/drivers/tty/serial/8250_pci.c +++ b/drivers/tty/serial/8250_pci.c @@ -973,7 +973,7 @@ ce4100_serial_setup(struct serial_private *priv, static int pci_omegapci_setup(struct serial_private *priv, - struct pciserial_board *board, + const struct pciserial_board *board, struct uart_port *port, int idx) { return setup_port(priv, port, 2, idx * 8, 0); From cb01ece3ea5dec16ac7bab30069c7736b59f7dea Mon Sep 17 00:00:00 2001 From: "leitao@linux.vnet.ibm.com" Date: Thu, 26 May 2011 11:18:39 -0300 Subject: [PATCH 05/12] 8250: Fix capabilities when changing the port type When changing the port type, the capabilities flags should be changed also, otherwise the capabilities will not correspond to the port type, which make set_sleep() crash on rmmod. This patch just assign the correct capabilites when the port changes. Signed-off-by: Breno Leitao CC: Michael Reed Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/8250.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/tty/serial/8250.c b/drivers/tty/serial/8250.c index b40f7b90c81d..b4129f53fb1b 100644 --- a/drivers/tty/serial/8250.c +++ b/drivers/tty/serial/8250.c @@ -3318,6 +3318,7 @@ void serial8250_unregister_port(int line) uart->port.flags &= ~UPF_BOOT_AUTOCONF; uart->port.type = PORT_UNKNOWN; uart->port.dev = &serial8250_isa_devs->dev; + uart->capabilities = uart_config[uart->port.type].flags; uart_add_one_port(&serial8250_reg, &uart->port); } else { uart->port.dev = NULL; From 92f6fa09bd453ffe3351fa1f1377a1b7cfa911e6 Mon Sep 17 00:00:00 2001 From: Jiri Slaby Date: Sun, 5 Jun 2011 14:16:16 +0200 Subject: [PATCH 06/12] TTY: ldisc, do not close until there are readers We restored tty_ldisc_wait_idle in 100eeae2c5c (TTY: restore tty_ldisc_wait_idle). We used it in the ldisc changing path to fix the case where there are tasks in n_tty_read waiting for data and somebody tries to change ldisc. Similar to the case above, there may be also tasks waiting in n_tty_read while hangup is performed. As 65b770468e98 (tty-ldisc: turn ldisc user count into a proper refcount) removed the wait-until-idle from all paths, hangup path won't wait for them to disappear either now. So add it back even to the hangup path. There is a difference, we need uninterruptible sleep as there is obviously HUP signal pending. So tty_ldisc_wait_idle now sleeps without possibility to be interrupted. This is what original tty_ldisc_wait_idle did. After the wait idle reintroduction (100eeae2c5c), we have had interruptible sleeps for the ldisc changing path. But as there is a 5s timeout anyway, we don't allow it to be interrupted from now on. It's not worth the added complexity of deciding what kind of sleep we want. Before 65b770468e98 tty_ldisc_release was called also from tty_ldisc_release. It is called from tty_release, so I don't think we need to restore that one. This is nicely reproducible after constifying the timing when drivers/tty/n_tty.c is patched as follows ("TTY: ntty, add one more sanity check" patch is needed to actually see it explode): %% -1548,6 +1549,7 @@ static int n_tty_open(struct tty_struct *tty) /* These are ugly. Currently a malloc failure here can panic */ if (!tty->read_buf) { + msleep(100); tty->read_buf = kzalloc(N_TTY_BUF_SIZE, GFP_KERNEL); if (!tty->read_buf) return -ENOMEM; %% -1785,6 +1788,7 @@ do_it_again: break; } timeout = schedule_timeout(timeout); + msleep(20); continue; } __set_current_state(TASK_RUNNING); ===== With a process: ===== while (1) { int fd = open(argv[1], O_RDWR); read(fd, buf, sizeof(buf)); close(fd); } ===== and its child: ===== setsid(); while (1) { int fd = open(tty, O_RDWR|O_NOCTTY); ioctl(fd, TIOCSCTTY, 1); vhangup(); close(fd); usleep(100 * (10 + random() % 1000)); } ===== EOF ===== References: https://bugzilla.novell.com/show_bug.cgi?id=693374 References: https://bugzilla.novell.com/show_bug.cgi?id=694509 Signed-off-by: Jiri Slaby Cc: Alan Cox Cc: Linus Torvalds Cc: stable [32, 33, 34, 39] Signed-off-by: Greg Kroah-Hartman --- drivers/tty/tty_ldisc.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c index 5d01d32e2cf0..ef925d581713 100644 --- a/drivers/tty/tty_ldisc.c +++ b/drivers/tty/tty_ldisc.c @@ -555,7 +555,7 @@ static void tty_ldisc_flush_works(struct tty_struct *tty) static int tty_ldisc_wait_idle(struct tty_struct *tty) { int ret; - ret = wait_event_interruptible_timeout(tty_ldisc_idle, + ret = wait_event_timeout(tty_ldisc_idle, atomic_read(&tty->ldisc->users) == 1, 5 * HZ); if (ret < 0) return ret; @@ -763,6 +763,8 @@ static int tty_ldisc_reinit(struct tty_struct *tty, int ldisc) if (IS_ERR(ld)) return -1; + WARN_ON_ONCE(tty_ldisc_wait_idle(tty)); + tty_ldisc_close(tty, tty->ldisc); tty_ldisc_put(tty->ldisc); tty->ldisc = NULL; From 2872628680bad71a6734e7d379168f990a91cc09 Mon Sep 17 00:00:00 2001 From: Jiri Slaby Date: Sun, 5 Jun 2011 14:16:17 +0200 Subject: [PATCH 07/12] TTY: ntty, add one more sanity check With the previous patch, we fixed another bug where read_buf was freed while we still was in n_tty_read. We currently check whether read_buf is NULL at the start of the function. Add one more check after we wake up from waiting for input. Signed-off-by: Jiri Slaby Cc: Alan Cox Signed-off-by: Greg Kroah-Hartman --- drivers/tty/n_tty.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c index 0ad32888091c..c3954fbf6ac4 100644 --- a/drivers/tty/n_tty.c +++ b/drivers/tty/n_tty.c @@ -1815,6 +1815,7 @@ do_it_again: /* FIXME: does n_tty_set_room need locking ? */ n_tty_set_room(tty); timeout = schedule_timeout(timeout); + BUG_ON(!tty->read_buf); continue; } __set_current_state(TASK_RUNNING); From 7263287af93db4d5cf324a30546f2143419b7900 Mon Sep 17 00:00:00 2001 From: Russ Gorby Date: Tue, 14 Jun 2011 13:23:28 -0700 Subject: [PATCH 08/12] tty: n_gsm: Fixed logic to decode break signal from modem status The modem status can be one or 2 octets and contains the V.24 signals and in the 2 octet case also the break signal. We were improperly decoding the break signal from the modem in the 2 octet case. Signed-off-by: Russ Gorby Signed-off-by: Greg Kroah-Hartman --- drivers/tty/n_gsm.c | 23 ++++++++++++++++++----- 1 file changed, 18 insertions(+), 5 deletions(-) diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index 09e8c7d53af3..7290394e3131 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -984,10 +984,22 @@ static void gsm_control_reply(struct gsm_mux *gsm, int cmd, u8 *data, */ static void gsm_process_modem(struct tty_struct *tty, struct gsm_dlci *dlci, - u32 modem) + u32 modem, int clen) { int mlines = 0; - u8 brk = modem >> 6; + u8 brk = 0; + + /* The modem status command can either contain one octet (v.24 signals) + or two octets (v.24 signals + break signals). The length field will + either be 2 or 3 respectively. This is specified in section + 5.4.6.3.7 of the 27.010 mux spec. */ + + if (clen == 2) + modem = modem & 0x7f; + else { + brk = modem & 0x7f; + modem = (modem >> 7) & 0x7f; + }; /* Flow control/ready to communicate */ if (modem & MDM_FC) { @@ -1061,7 +1073,7 @@ static void gsm_control_modem(struct gsm_mux *gsm, u8 *data, int clen) return; } tty = tty_port_tty_get(&dlci->port); - gsm_process_modem(tty, dlci, modem); + gsm_process_modem(tty, dlci, modem, clen); if (tty) { tty_wakeup(tty); tty_kref_put(tty); @@ -1482,12 +1494,13 @@ static void gsm_dlci_begin_close(struct gsm_dlci *dlci) * open we shovel the bits down it, if not we drop them. */ -static void gsm_dlci_data(struct gsm_dlci *dlci, u8 *data, int len) +static void gsm_dlci_data(struct gsm_dlci *dlci, u8 *data, int clen) { /* krefs .. */ struct tty_port *port = &dlci->port; struct tty_struct *tty = tty_port_tty_get(port); unsigned int modem = 0; + int len = clen; if (debug & 16) pr_debug("%d bytes for tty %p\n", len, tty); @@ -1507,7 +1520,7 @@ static void gsm_dlci_data(struct gsm_dlci *dlci, u8 *data, int len) if (len == 0) return; } - gsm_process_modem(tty, dlci, modem); + gsm_process_modem(tty, dlci, modem, clen); /* Line state will go via DLCI 0 controls only */ case 1: default: From 57f2104f39995bac332ddc492fbf60aa28e0c35e Mon Sep 17 00:00:00 2001 From: Russ Gorby Date: Tue, 14 Jun 2011 13:23:29 -0700 Subject: [PATCH 09/12] tty: n_gsm: improper skb_pull() use was leaking framed data gsm_dlci_data_output_framed() was doing: memcpy(dp, skb_pull(dlci->skb, len), len); The problem is skb_pull() returns the post-increment data ptr so the first chunk of dlci->skb->data is leaked. Signed-off-by: Russ Gorby Signed-off-by: Greg Kroah-Hartman --- drivers/tty/n_gsm.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/tty/n_gsm.c b/drivers/tty/n_gsm.c index 7290394e3131..19b4ae052af8 100644 --- a/drivers/tty/n_gsm.c +++ b/drivers/tty/n_gsm.c @@ -875,7 +875,8 @@ static int gsm_dlci_data_output_framed(struct gsm_mux *gsm, *dp++ = last << 7 | first << 6 | 1; /* EA */ len--; } - memcpy(dp, skb_pull(dlci->skb, len), len); + memcpy(dp, dlci->skb->data, len); + skb_pull(dlci->skb, len); __gsm_data_queue(dlci, msg); if (last) dlci->skb = NULL; From c16d51a32bbb61ac8fd96f78b5ce2fccfe0fb4c3 Mon Sep 17 00:00:00 2001 From: Shreshtha Kumar Sahu Date: Mon, 13 Jun 2011 10:11:33 +0200 Subject: [PATCH 10/12] amba pl011: workaround for uart registers lockup This workaround aims to break the deadlock situation which raises during continuous transfer of data for long duration over uart with hardware flow control. It is observed that CTS interrupt cannot be cleared in uart interrupt register (ICR). Hence further transfer over uart gets blocked. It is seen that during such deadlock condition ICR don't get cleared even on multiple write. This leads pass_counter to decrease and finally reach zero. This can be taken as trigger point to run this UART_BT_WA. Workaround backups the register configuration, does soft reset of UART using BIT-0 of PRCC_K_SOFTRST_SET/CLEAR registers and restores the registers. This patch also provides support for uart init and exit function calls if present. Signed-off-by: Shreshtha Kumar Sahu Signed-off-by: Linus Walleij Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/amba-pl011.c | 123 +++++++++++++++++++++++++++++++- include/linux/amba/serial.h | 3 + 2 files changed, 125 insertions(+), 1 deletion(-) diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index 8dc0541feecc..f5f6831b0a64 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -50,6 +50,7 @@ #include #include #include +#include #include #include @@ -65,6 +66,30 @@ #define UART_DR_ERROR (UART011_DR_OE|UART011_DR_BE|UART011_DR_PE|UART011_DR_FE) #define UART_DUMMY_DR_RX (1 << 16) + +#define UART_WA_SAVE_NR 14 + +static void pl011_lockup_wa(unsigned long data); +static const u32 uart_wa_reg[UART_WA_SAVE_NR] = { + ST_UART011_DMAWM, + ST_UART011_TIMEOUT, + ST_UART011_LCRH_RX, + UART011_IBRD, + UART011_FBRD, + ST_UART011_LCRH_TX, + UART011_IFLS, + ST_UART011_XFCR, + ST_UART011_XON1, + ST_UART011_XON2, + ST_UART011_XOFF1, + ST_UART011_XOFF2, + UART011_CR, + UART011_IMSC +}; + +static u32 uart_wa_regdata[UART_WA_SAVE_NR]; +static DECLARE_TASKLET(pl011_lockup_tlet, pl011_lockup_wa, 0); + /* There is by now at least one vendor with differing details, so handle it */ struct vendor_data { unsigned int ifls; @@ -72,6 +97,7 @@ struct vendor_data { unsigned int lcrh_tx; unsigned int lcrh_rx; bool oversampling; + bool interrupt_may_hang; /* vendor-specific */ bool dma_threshold; }; @@ -90,9 +116,12 @@ 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, }; +static struct uart_amba_port *amba_ports[UART_NR]; + /* Deals with DMA transactions */ struct pl011_sgbuf { @@ -132,6 +161,7 @@ struct uart_amba_port { unsigned int lcrh_rx; /* vendor-specific */ bool autorts; char type[12]; + bool interrupt_may_hang; /* vendor-specific */ #ifdef CONFIG_DMA_ENGINE /* DMA stuff */ bool using_tx_dma; @@ -1008,6 +1038,68 @@ static inline bool pl011_dma_rx_running(struct uart_amba_port *uap) #endif +/* + * pl011_lockup_wa + * This workaround aims to break the deadlock situation + * when after long transfer over uart in hardware flow + * control, uart interrupt registers cannot be cleared. + * Hence uart transfer gets blocked. + * + * It is seen that during such deadlock condition ICR + * don't get cleared even on multiple write. This leads + * pass_counter to decrease and finally reach zero. This + * can be taken as trigger point to run this UART_BT_WA. + * + */ +static void pl011_lockup_wa(unsigned long data) +{ + struct uart_amba_port *uap = amba_ports[0]; + void __iomem *base = uap->port.membase; + struct circ_buf *xmit = &uap->port.state->xmit; + struct tty_struct *tty = uap->port.state->port.tty; + int buf_empty_retries = 200; + int loop; + + /* Stop HCI layer from submitting data for tx */ + tty->hw_stopped = 1; + while (!uart_circ_empty(xmit)) { + if (buf_empty_retries-- == 0) + break; + udelay(100); + } + + /* Backup registers */ + for (loop = 0; loop < UART_WA_SAVE_NR; loop++) + uart_wa_regdata[loop] = readl(base + uart_wa_reg[loop]); + + /* Disable UART so that FIFO data is flushed out */ + writew(0x00, uap->port.membase + UART011_CR); + + /* Soft reset UART module */ + if (uap->port.dev->platform_data) { + struct amba_pl011_data *plat; + + plat = uap->port.dev->platform_data; + if (plat->reset) + plat->reset(); + } + + /* Restore registers */ + for (loop = 0; loop < UART_WA_SAVE_NR; loop++) + writew(uart_wa_regdata[loop] , + uap->port.membase + uart_wa_reg[loop]); + + /* Initialise the old status of the modem signals */ + uap->old_status = readw(uap->port.membase + UART01x_FR) & + UART01x_FR_MODEM_ANY; + + if (readl(base + UART011_MIS) & 0x2) + printk(KERN_EMERG "UART_BT_WA: ***FAILED***\n"); + + /* Start Tx/Rx */ + tty->hw_stopped = 0; +} + static void pl011_stop_tx(struct uart_port *port) { struct uart_amba_port *uap = (struct uart_amba_port *)port; @@ -1158,8 +1250,11 @@ static irqreturn_t pl011_int(int irq, void *dev_id) if (status & UART011_TXIS) pl011_tx_chars(uap); - if (pass_counter-- == 0) + if (pass_counter-- == 0) { + if (uap->interrupt_may_hang) + tasklet_schedule(&pl011_lockup_tlet); break; + } status = readw(uap->port.membase + UART011_MIS); } while (status != 0); @@ -1339,6 +1434,14 @@ 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: @@ -1394,6 +1497,15 @@ static void pl011_shutdown(struct uart_port *port) * Shut down the clock producer */ clk_disable(uap->clk); + + if (uap->port.dev->platform_data) { + struct amba_pl011_data *plat; + + plat = uap->port.dev->platform_data; + if (plat->exit) + plat->exit(); + } + } static void @@ -1700,6 +1812,14 @@ static int __init pl011_console_setup(struct console *co, char *options) if (!uap) return -ENODEV; + if (uap->port.dev->platform_data) { + struct amba_pl011_data *plat; + + plat = uap->port.dev->platform_data; + if (plat->init) + plat->init(); + } + uap->port.uartclk = clk_get_rate(uap->clk); if (options) @@ -1774,6 +1894,7 @@ static int pl011_probe(struct amba_device *dev, const struct amba_id *id) uap->lcrh_rx = vendor->lcrh_rx; uap->lcrh_tx = vendor->lcrh_tx; 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; diff --git a/include/linux/amba/serial.h b/include/linux/amba/serial.h index 5479fdc849e9..514ed45c462e 100644 --- a/include/linux/amba/serial.h +++ b/include/linux/amba/serial.h @@ -201,6 +201,9 @@ struct amba_pl011_data { bool (*dma_filter)(struct dma_chan *chan, void *filter_param); void *dma_rx_param; void *dma_tx_param; + void (*init) (void); + void (*exit) (void); + void (*reset) (void); }; #endif From 1a7d4369b3fe1f8e5efe7f11a1c482055693852f Mon Sep 17 00:00:00 2001 From: Shreshtha Kumar Sahu Date: Mon, 13 Jun 2011 10:11:44 +0200 Subject: [PATCH 11/12] amba pl011: platform data for reg lockup and glitch v2 This patch provides platform data for following - uart reset function to assist uart register lockup workaround - init/exit function to fix glitch in the tx pin in tty_open when tty port0 is opened a glitch is seen in the tx line of uart0. This happens in pl011_startup() when tx fifo interrupt is provoked into asserting. Now uart0 pins are enabled (alt function) only when init is complete and turned back to gpio when closed. Signed-off-by: Shreshtha Kumar Sahu Signed-off-by: Linus Walleij Signed-off-by: Greg Kroah-Hartman --- arch/arm/mach-ux500/board-mop500-pins.c | 16 ++++++-- arch/arm/mach-ux500/board-mop500.c | 54 +++++++++++++++++++++++++ 2 files changed, 66 insertions(+), 4 deletions(-) diff --git a/arch/arm/mach-ux500/board-mop500-pins.c b/arch/arm/mach-ux500/board-mop500-pins.c index fd4cf1ca5efd..70cdbd60596a 100644 --- a/arch/arm/mach-ux500/board-mop500-pins.c +++ b/arch/arm/mach-ux500/board-mop500-pins.c @@ -110,10 +110,18 @@ static pin_cfg_t mop500_pins_common[] = { GPIO168_KP_O0, /* UART */ - GPIO0_U0_CTSn | PIN_INPUT_PULLUP, - GPIO1_U0_RTSn | PIN_OUTPUT_HIGH, - GPIO2_U0_RXD | PIN_INPUT_PULLUP, - GPIO3_U0_TXD | PIN_OUTPUT_HIGH, + /* uart-0 pins gpio configuration should be + * kept intact to prevent glitch in tx line + * when tty dev is opened. Later these pins + * are configured to uart mop500_pins_uart0 + * + * It will be replaced with uart configuration + * once the issue is solved. + */ + GPIO0_GPIO | PIN_INPUT_PULLUP, + GPIO1_GPIO | PIN_OUTPUT_HIGH, + GPIO2_GPIO | PIN_INPUT_PULLUP, + GPIO3_GPIO | PIN_OUTPUT_HIGH, GPIO29_U2_RXD | PIN_INPUT_PULLUP, GPIO30_U2_TXD | PIN_OUTPUT_HIGH, diff --git a/arch/arm/mach-ux500/board-mop500.c b/arch/arm/mach-ux500/board-mop500.c index bb26f40493e6..2a08c07dec6d 100644 --- a/arch/arm/mach-ux500/board-mop500.c +++ b/arch/arm/mach-ux500/board-mop500.c @@ -27,18 +27,21 @@ #include #include #include +#include #include #include #include #include +#include #include #include #include #include +#include "pins-db8500.h" #include "ste-dma40-db8500.h" #include "devices-db8500.h" #include "board-mop500.h" @@ -393,12 +396,63 @@ static struct stedma40_chan_cfg uart2_dma_cfg_tx = { }; #endif + +static pin_cfg_t mop500_pins_uart0[] = { + GPIO0_U0_CTSn | PIN_INPUT_PULLUP, + GPIO1_U0_RTSn | PIN_OUTPUT_HIGH, + GPIO2_U0_RXD | PIN_INPUT_PULLUP, + GPIO3_U0_TXD | PIN_OUTPUT_HIGH, +}; + +#define PRCC_K_SOFTRST_SET 0x18 +#define PRCC_K_SOFTRST_CLEAR 0x1C +static void ux500_uart0_reset(void) +{ + void __iomem *prcc_rst_set, *prcc_rst_clr; + + prcc_rst_set = (void __iomem *)IO_ADDRESS(U8500_CLKRST1_BASE + + PRCC_K_SOFTRST_SET); + prcc_rst_clr = (void __iomem *)IO_ADDRESS(U8500_CLKRST1_BASE + + PRCC_K_SOFTRST_CLEAR); + + /* Activate soft reset PRCC_K_SOFTRST_CLEAR */ + writel((readl(prcc_rst_clr) | 0x1), prcc_rst_clr); + udelay(1); + + /* Release soft reset PRCC_K_SOFTRST_SET */ + writel((readl(prcc_rst_set) | 0x1), prcc_rst_set); + udelay(1); +} + +static void ux500_uart0_init(void) +{ + int ret; + + ret = nmk_config_pins(mop500_pins_uart0, + ARRAY_SIZE(mop500_pins_uart0)); + if (ret < 0) + pr_err("pl011: uart pins_enable failed\n"); +} + +static void ux500_uart0_exit(void) +{ + int ret; + + ret = nmk_config_pins_sleep(mop500_pins_uart0, + ARRAY_SIZE(mop500_pins_uart0)); + if (ret < 0) + pr_err("pl011: uart pins_disable failed\n"); +} + static struct amba_pl011_data uart0_plat = { #ifdef CONFIG_STE_DMA40 .dma_filter = stedma40_filter, .dma_rx_param = &uart0_dma_cfg_rx, .dma_tx_param = &uart0_dma_cfg_tx, #endif + .init = ux500_uart0_init, + .exit = ux500_uart0_exit, + .reset = ux500_uart0_reset, }; static struct amba_pl011_data uart1_plat = { From 3bc46b312b1486b1fe2db4246a34a30160d26d8d Mon Sep 17 00:00:00 2001 From: Maxime Bizon Date: Fri, 10 Jun 2011 23:17:58 +0200 Subject: [PATCH 12/12] serial: bcm63xx_uart: fix irq storm after rx fifo overrun. RX fifo reset is required to clear irq. Signed-off-by: Maxime Bizon Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/bcm63xx_uart.c | 18 ++++++++++++++---- 1 file changed, 14 insertions(+), 4 deletions(-) diff --git a/drivers/tty/serial/bcm63xx_uart.c b/drivers/tty/serial/bcm63xx_uart.c index a1a0e55d0807..c0b68b9cad91 100644 --- a/drivers/tty/serial/bcm63xx_uart.c +++ b/drivers/tty/serial/bcm63xx_uart.c @@ -250,6 +250,20 @@ static void bcm_uart_do_rx(struct uart_port *port) /* get overrun/fifo empty information from ier * register */ iestat = bcm_uart_readl(port, UART_IR_REG); + + if (unlikely(iestat & UART_IR_STAT(UART_IR_RXOVER))) { + unsigned int val; + + /* fifo reset is required to clear + * interrupt */ + val = bcm_uart_readl(port, UART_CTL_REG); + val |= UART_CTL_RSTRXFIFO_MASK; + bcm_uart_writel(port, val, UART_CTL_REG); + + port->icount.overrun++; + tty_insert_flip_char(tty, 0, TTY_OVERRUN); + } + if (!(iestat & UART_IR_STAT(UART_IR_RXNOTEMPTY))) break; @@ -284,10 +298,6 @@ static void bcm_uart_do_rx(struct uart_port *port) if (uart_handle_sysrq_char(port, c)) continue; - if (unlikely(iestat & UART_IR_STAT(UART_IR_RXOVER))) { - port->icount.overrun++; - tty_insert_flip_char(tty, 0, TTY_OVERRUN); - } if ((cstat & port->ignore_status_mask) == 0) tty_insert_flip_char(tty, c, flag);