From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2E3C426868E; Tue, 27 May 2025 17:05:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748365532; cv=none; b=J/4GPRFFY88fkSwRqsyCUtzJk9h4EbOIPRnYjqcFygmSQ5RiIkLwQZHJyzVxdc2TX8HhXOPFQKwiuyzd2F/xSGwuWhgRx8DP370VRbZ5xw5/UIZrDyXIF5iaaDJk5iZOhw9xdyZzD6ZWAXvAfCK0EEY3Tn5ONIq+9a0GSqarNYM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748365532; c=relaxed/simple; bh=6x0jXoFpnd8iMwZIDKzHVAnZUBNfxtcYkrDBZ/baO1I=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=LgM+7/F1/0vqBlc40Xshda4+VnNKdEivKWtFJJN2QauQU5l1nC4eo0BhTJkPwLfBpJv4euYSd77p4K/VzgNZfE1/oJ3uuqvrB+lBvvwlAkr8Imtnavm1K7EyhIlNfqFzCQ15ZtiQfjgHXzIc9d16Hf6xfIBi2DLkWKQFHdxa6AU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=zsMFDe3g; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="zsMFDe3g" Received: by smtp.kernel.org (Postfix) with ESMTPSA id ABB16C4CEE9; Tue, 27 May 2025 17:05:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1748365532; bh=6x0jXoFpnd8iMwZIDKzHVAnZUBNfxtcYkrDBZ/baO1I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zsMFDe3gZI/M2C5vglwc2PvAHG5hO9Ce5mcEU9XLmfTbmkvw1pfrEinxSbWogD7f2 zFwMdeuhZt6CvA8dZ9N9Wqkz6SxEzwYebQ4rHHTkjhY/vG1DXrjtRq4ne97GY87CP8 b0iOW/UFpPfPONskQ0jSkVRhhHpDv5WAG1BSfrU0= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Claudiu Beznea , Geert Uytterhoeven , Sasha Levin Subject: [PATCH 6.12 379/626] serial: sh-sci: Update the suspend/resume support Date: Tue, 27 May 2025 18:24:32 +0200 Message-ID: <20250527162500.414638820@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250527162445.028718347@linuxfoundation.org> References: <20250527162445.028718347@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Claudiu Beznea [ Upstream commit 22a6984c5b5df8eab864d7f3e8b94d5a554d31ab ] The Renesas RZ/G3S supports a power saving mode where power to most of the SoC components is turned off. When returning from this power saving mode, SoC components need to be re-configured. The SCIFs on the Renesas RZ/G3S need to be re-configured as well when returning from this power saving mode. The sh-sci code already configures the SCIF clocks, power domain and registers by calling uart_resume_port() in sci_resume(). On suspend path the SCIF UART ports are suspended accordingly (by calling uart_suspend_port() in sci_suspend()). The only missing setting is the reset signal. For this assert/de-assert the reset signal on driver suspend/resume. In case the no_console_suspend is specified by the user, the registers need to be saved on suspend path and restore on resume path. To do this the sci_console_save()/sci_console_restore() functions were added. There is no need to cache/restore the status or FIFO registers. Only the control registers. The registers that will be saved/restored on suspend/resume are specified by the struct sci_suspend_regs data structure. Signed-off-by: Claudiu Beznea Reviewed-by: Geert Uytterhoeven Link: https://lore.kernel.org/r/20250207113313.545432-1-claudiu.beznea.uj@bp.renesas.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- drivers/tty/serial/sh-sci.c | 71 +++++++++++++++++++++++++++++++++++-- 1 file changed, 69 insertions(+), 2 deletions(-) diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c index 80efe3b0ed0c3..779074b1c2be4 100644 --- a/drivers/tty/serial/sh-sci.c +++ b/drivers/tty/serial/sh-sci.c @@ -104,6 +104,15 @@ struct plat_sci_reg { u8 offset, size; }; +struct sci_suspend_regs { + u16 scsmr; + u16 scscr; + u16 scfcr; + u16 scsptr; + u8 scbrr; + u8 semr; +}; + struct sci_port_params { const struct plat_sci_reg regs[SCIx_NR_REGS]; unsigned int fifosize; @@ -134,6 +143,8 @@ struct sci_port { struct dma_chan *chan_tx; struct dma_chan *chan_rx; + struct reset_control *rstc; + #ifdef CONFIG_SERIAL_SH_SCI_DMA struct dma_chan *chan_tx_saved; struct dma_chan *chan_rx_saved; @@ -153,6 +164,7 @@ struct sci_port { int rx_trigger; struct timer_list rx_fifo_timer; int rx_fifo_timeout; + struct sci_suspend_regs suspend_regs; u16 hscif_tot; bool has_rtscts; @@ -3384,6 +3396,7 @@ static struct plat_sci_port *sci_parse_dt(struct platform_device *pdev, } sp = &sci_ports[id]; + sp->rstc = rstc; *dev_id = id; p->type = SCI_OF_TYPE(data); @@ -3532,13 +3545,57 @@ static int sci_probe(struct platform_device *dev) return 0; } +static void sci_console_save(struct sci_port *s) +{ + struct sci_suspend_regs *regs = &s->suspend_regs; + struct uart_port *port = &s->port; + + if (sci_getreg(port, SCSMR)->size) + regs->scsmr = sci_serial_in(port, SCSMR); + if (sci_getreg(port, SCSCR)->size) + regs->scscr = sci_serial_in(port, SCSCR); + if (sci_getreg(port, SCFCR)->size) + regs->scfcr = sci_serial_in(port, SCFCR); + if (sci_getreg(port, SCSPTR)->size) + regs->scsptr = sci_serial_in(port, SCSPTR); + if (sci_getreg(port, SCBRR)->size) + regs->scbrr = sci_serial_in(port, SCBRR); + if (sci_getreg(port, SEMR)->size) + regs->semr = sci_serial_in(port, SEMR); +} + +static void sci_console_restore(struct sci_port *s) +{ + struct sci_suspend_regs *regs = &s->suspend_regs; + struct uart_port *port = &s->port; + + if (sci_getreg(port, SCSMR)->size) + sci_serial_out(port, SCSMR, regs->scsmr); + if (sci_getreg(port, SCSCR)->size) + sci_serial_out(port, SCSCR, regs->scscr); + if (sci_getreg(port, SCFCR)->size) + sci_serial_out(port, SCFCR, regs->scfcr); + if (sci_getreg(port, SCSPTR)->size) + sci_serial_out(port, SCSPTR, regs->scsptr); + if (sci_getreg(port, SCBRR)->size) + sci_serial_out(port, SCBRR, regs->scbrr); + if (sci_getreg(port, SEMR)->size) + sci_serial_out(port, SEMR, regs->semr); +} + static __maybe_unused int sci_suspend(struct device *dev) { struct sci_port *sport = dev_get_drvdata(dev); - if (sport) + if (sport) { uart_suspend_port(&sci_uart_driver, &sport->port); + if (!console_suspend_enabled && uart_console(&sport->port)) + sci_console_save(sport); + else + return reset_control_assert(sport->rstc); + } + return 0; } @@ -3546,8 +3603,18 @@ static __maybe_unused int sci_resume(struct device *dev) { struct sci_port *sport = dev_get_drvdata(dev); - if (sport) + if (sport) { + if (!console_suspend_enabled && uart_console(&sport->port)) { + sci_console_restore(sport); + } else { + int ret = reset_control_deassert(sport->rstc); + + if (ret) + return ret; + } + uart_resume_port(&sci_uart_driver, &sport->port); + } return 0; } -- 2.39.5