From: David Laight <David.Laight@ACULAB.COM>
To: 'Jiri Slaby' <jirislaby@kernel.org>, Lee Jones <lee.jones@linaro.org>
Cc: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"Greg Kroah-Hartman" <gregkh@linuxfoundation.org>,
"paulkf@microgate.com" <paulkf@microgate.com>
Subject: RE: [PATCH 27/36] tty: synclinkmp: Mark never checked 'readval' as __always_unused
Date: Thu, 5 Nov 2020 11:04:54 +0000 [thread overview]
Message-ID: <6515b9ff5a9343f5a713e337f41450cc@AcuMS.aculab.com> (raw)
In-Reply-To: <a95f8d0d-28ef-7351-cdbb-7da5ad8aa9ad@kernel.org>
> >> And the loop can be turned into ndelay:
> >>
> >> /*
> >> * Force at least 170ns delay before clearing
> >> * reset bit. Each read from LCR takes at least
> >> * 30ns so 10 times for 300ns to be safe.
> >> */
> >> for(i=0;i<10;i++)
> >> readval = *MiscCtrl;
> >
> > Again, since I can't test this, I do not want this patch to contain
> > any functional changes. AFAIC, the 10 register reads must still
> > happen after this patch is applied.
You can't use ndelay(); the writes can get posted so can appear
much closer together by the time they get to the actual hardware.
Multiple volatile reads don't need a target variable.
(Shouldn't they also real readl()?)
Deleting the driver works...
David
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next prev parent reply other threads:[~2020-11-05 11:05 UTC|newest]
Thread overview: 84+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-04 19:35 [PATCH 00/36] Rid W=1 issues from TTY Lee Jones
2020-11-04 19:35 ` [PATCH 01/36] tty: serdev: core: Remove unused variable 'dummy' Lee Jones
2020-11-04 19:35 ` [PATCH 02/36] tty: serdev: core: Provide missing description for 'owner' Lee Jones
2020-11-04 19:35 ` [PATCH 03/36] tty: tty_baudrate: Add missing description for 'tty' Lee Jones
2020-11-04 19:35 ` [PATCH 04/36] tty: tty_io: Move 'tty_sysctl_init's prototype to shared space Lee Jones
2020-11-04 19:35 ` [PATCH 05/36] tty: tty_buffer: Add missing description for 'limit' Lee Jones
2020-11-04 19:35 ` [PATCH 06/36] tty: tty_port: Demote obvious abuse of kernel-doc formatting Lee Jones
2020-11-04 19:35 ` [PATCH 07/36] tty: tty_jobctrl: Add missing function parameter descriptions Lee Jones
2020-11-04 19:35 ` [PATCH 08/36] tty: tty_ldisc: Fix some kernel-doc related misdemeanours Lee Jones
2020-11-05 8:12 ` Jiri Slaby
2020-11-05 8:54 ` Lee Jones
2020-11-05 8:56 ` Lee Jones
2020-11-04 19:35 ` [PATCH 09/36] tty: vt: consolemap: Demote weakly documented function header Lee Jones
2020-11-04 19:35 ` [PATCH 10/36] tty: n_tty: Add 2 missing parameter descriptions Lee Jones
2020-11-04 19:35 ` [PATCH 11/36] tty: serial: jsm: jsm_cls: Remove unused variable 'discard' Lee Jones
2020-11-04 19:35 ` [PATCH 12/36] tty: tty_io: Fix some kernel-doc issues Lee Jones
2020-11-05 8:16 ` Jiri Slaby
2020-11-05 8:53 ` Lee Jones
2020-11-05 9:14 ` Jiri Slaby
2020-11-04 19:35 ` [PATCH 13/36] tty: serial: 8250: 8250_port: Staticify functions referenced by pointers Lee Jones
2020-11-06 9:53 ` Greg Kroah-Hartman
2020-11-06 10:05 ` Lee Jones
2020-11-06 10:16 ` Lee Jones
2020-11-06 10:39 ` Greg Kroah-Hartman
2020-11-06 10:48 ` Lee Jones
2020-11-06 10:55 ` Greg Kroah-Hartman
2020-11-06 11:12 ` Lee Jones
2020-11-06 11:19 ` Jiri Slaby
2020-11-06 14:47 ` Lee Jones
2020-11-06 10:20 ` Greg Kroah-Hartman
2020-11-06 10:47 ` Lee Jones
2020-11-04 19:35 ` [PATCH 14/36] tty: serial: 8250: serial_cs: Remove unused/unchecked variable 'err' Lee Jones
2020-11-04 19:35 ` [PATCH 15/36] tty: tty_audit: Demote non-conformant kernel-doc headers Lee Jones
2020-11-04 19:35 ` [PATCH 16/36] tty: pty: Provide descriptions for the 'file' parameters Lee Jones
2020-11-04 19:35 ` [PATCH 17/36] tty: serial: amba-pl011: Mark 'sbsa_uart_acpi_match' as __maybe_unused Lee Jones
2020-11-04 19:35 ` [PATCH 18/36] tty: n_gsm: Demote obvious abuse of kernel-doc and supply other missing docss Lee Jones
2020-11-04 19:35 ` [PATCH 19/36] tty: serial: lpc32xx_hs: Remove unused variable 'tmp' Lee Jones
2020-11-04 20:04 ` Vladimir Zapolskiy
2020-11-04 19:35 ` [PATCH 20/36] tty: serial: msm_serial: Remove set but unused variable 'status' Lee Jones
2020-11-05 16:09 ` Jeffrey Hugo
2020-11-04 19:35 ` [PATCH 21/36] tty: serial: ifx6x60: Fix function documentation headers Lee Jones
2020-11-04 19:35 ` [PATCH 22/36] tty: serial: xilinx_uartps: Supply description for missing member 'cts_override' Lee Jones
2020-11-16 10:55 ` Maarten Brock
2020-11-16 12:38 ` Lee Jones
2020-11-04 19:35 ` [PATCH 23/36] tty: synclink_gt: Demote one kernel-doc header and repair another Lee Jones
2020-11-04 19:35 ` [PATCH 24/36] tty: serial: serial-tegra: Struct headers should start with 'struct <name>' Lee Jones
2020-11-04 19:35 ` [PATCH 25/36] tty: serial: sifive: " Lee Jones
2020-11-06 8:11 ` Palmer Dabbelt
2020-11-04 19:35 ` [PATCH 26/36] tty: synclinkmp: Add missing description for function param 'txqueue' Lee Jones
2020-11-04 19:35 ` [PATCH 27/36] tty: synclinkmp: Mark never checked 'readval' as __always_unused Lee Jones
2020-11-05 8:28 ` Jiri Slaby
2020-11-05 8:43 ` Lee Jones
2020-11-05 9:10 ` Jiri Slaby
2020-11-05 9:39 ` Paul Fulghum
2020-11-05 9:55 ` Greg Kroah-Hartman
2020-11-05 10:05 ` Lee Jones
2020-11-05 10:54 ` Jiri Slaby
2020-11-05 11:04 ` David Laight [this message]
2020-11-05 11:27 ` Lee Jones
[not found] ` <54D08301-C89F-4AEB-B9A0-6CED6D5EEDA6@microgate.com>
2020-11-05 17:04 ` Paul Fulghum
2020-11-05 18:05 ` Lee Jones
2020-11-05 16:41 ` Jiri Slaby
2020-11-04 19:35 ` [PATCH 28/36] tty: serial: stm32-usart: Remove set but unused 'cookie' variables Lee Jones
2020-11-04 19:35 ` [PATCH 29/36] tty: tty_ldisc: Supply missing description for 'tty_ldisc_get's 'tty' param Lee Jones
2020-11-04 19:35 ` [PATCH 30/36] tty: serial: serial-tegra: Provide some missing struct member descriptions Lee Jones
2020-11-04 19:35 ` [PATCH 31/36] powerpc: asm: hvconsole: Move 'hvc_vio_init_early's prototype to shared location Lee Jones
2020-11-04 23:36 ` Michael Ellerman
2020-11-05 8:39 ` Lee Jones
2020-11-05 7:10 ` Christophe Leroy
2020-11-05 8:38 ` Lee Jones
2020-11-26 9:36 ` [PATCH v2 " Lee Jones
2020-11-04 19:35 ` [PATCH 32/36] tty: hvc: hvc_vio: Staticify function invoked only by reference Lee Jones
2020-11-04 19:35 ` [PATCH 33/36] tty: hvc: hvc_opal: Staticify function invoked " Lee Jones
2020-11-04 19:35 ` [PATCH 34/36] tty: serial: pmac_zilog: Make disposable variable __always_unused Lee Jones
2020-11-05 7:04 ` Christophe Leroy
2020-11-05 7:39 ` Jiri Slaby
2020-11-05 8:36 ` Lee Jones
2020-11-05 8:55 ` Jiri Slaby
2020-11-05 9:00 ` Lee Jones
2020-11-04 19:35 ` [PATCH 35/36] tty: synclink: Mark disposable variables as __always_unused Lee Jones
2020-11-05 8:35 ` Jiri Slaby
2020-11-05 9:00 ` Lee Jones
2020-11-04 19:35 ` [PATCH 36/36] tty: synclink: Provide missing description for 'hdlcdev_tx_timeout's 'txqueue' param Lee Jones
2020-11-06 9:54 ` [PATCH 00/36] Rid W=1 issues from TTY Greg Kroah-Hartman
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