Linux-PCI Archive on lore.kernel.org
 help / color / Atom feed
From: Thierry Reding <thierry.reding@gmail.com>
To: Manikanta Maddireddy <mmaddireddy@nvidia.com>
Cc: bhelgaas@google.com, robh+dt@kernel.org, mark.rutland@arm.com,
	jonathanh@nvidia.com, lorenzo.pieralisi@arm.com,
	vidyas@nvidia.com, linux-tegra@vger.kernel.org,
	linux-pci@vger.kernel.org, devicetree@vger.kernel.org
Subject: Re: [PATCH 29/30] PCI: tegra: Add support for GPIO based PCIe reset
Date: Mon, 15 Apr 2019 16:20:58 +0200
Message-ID: <20190415142058.GC29254@ulmo> (raw)
In-Reply-To: <20190411170355.6882-30-mmaddireddy@nvidia.com>

[-- Attachment #1: Type: text/plain, Size: 2876 bytes --]

On Thu, Apr 11, 2019 at 10:33:54PM +0530, Manikanta Maddireddy wrote:
> Add support for GPIO based PERST# instead of SFIO mode controller by AFI.
> GPIO number comes from per port PCIe device tree node.
> 
> Signed-off-by: Manikanta Maddireddy <mmaddireddy@nvidia.com>
> ---
>  drivers/pci/controller/pci-tegra.c | 37 +++++++++++++++++++++++++-----
>  1 file changed, 31 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/pci/controller/pci-tegra.c b/drivers/pci/controller/pci-tegra.c
> index 4a91c9fb3a9d..75873e6627f9 100644
> --- a/drivers/pci/controller/pci-tegra.c
> +++ b/drivers/pci/controller/pci-tegra.c
> @@ -17,6 +17,7 @@
>  #include <linux/debugfs.h>
>  #include <linux/delay.h>
>  #include <linux/export.h>
> +#include <linux/gpio.h>
>  #include <linux/interrupt.h>
>  #include <linux/iopoll.h>
>  #include <linux/irq.h>
> @@ -26,6 +27,7 @@
>  #include <linux/module.h>
>  #include <linux/msi.h>
>  #include <linux/of_address.h>
> +#include <linux/of_gpio.h>
>  #include <linux/of_pci.h>
>  #include <linux/of_platform.h>
>  #include <linux/pci.h>
> @@ -406,6 +408,7 @@ struct tegra_pcie_port {
>  
>  	int n_gpios;
>  	int *gpios;
> +	int rst_gpio;

This should be using GPIO descriptor APIs.

Thierry

>  };
>  
>  struct tegra_pcie_bus {
> @@ -589,15 +592,23 @@ static void tegra_pcie_port_reset(struct tegra_pcie_port *port)
>  	unsigned long value;
>  
>  	/* pulse reset signal */
> -	value = afi_readl(port->pcie, ctrl);
> -	value &= ~AFI_PEX_CTRL_RST;
> -	afi_writel(port->pcie, value, ctrl);
> +	if (gpio_is_valid(port->rst_gpio)) {
> +		gpio_set_value(port->rst_gpio, 0);
> +	} else {
> +		value = afi_readl(port->pcie, ctrl);
> +		value &= ~AFI_PEX_CTRL_RST;
> +		afi_writel(port->pcie, value, ctrl);
> +	}
>  
>  	usleep_range(1000, 2000);
>  
> -	value = afi_readl(port->pcie, ctrl);
> -	value |= AFI_PEX_CTRL_RST;
> -	afi_writel(port->pcie, value, ctrl);
> +	if (gpio_is_valid(port->rst_gpio)) {
> +		gpio_set_value(port->rst_gpio, 1);
> +	} else {
> +		value = afi_readl(port->pcie, ctrl);
> +		value |= AFI_PEX_CTRL_RST;
> +		afi_writel(port->pcie, value, ctrl);
> +	}
>  }
>  
>  static void tegra_pcie_enable_rp_features(struct tegra_pcie_port *port)
> @@ -2241,6 +2252,20 @@ static int tegra_pcie_parse_plat_dt(struct tegra_pcie_port *port,
>  		}
>  	}
>  
> +	port->rst_gpio = of_get_named_gpio(np, "nvidia,rst-gpio", 0);
> +	if (gpio_is_valid(port->rst_gpio)) {
> +		err = devm_gpio_request(dev, port->rst_gpio, "pex_rst_gpio");
> +		if (err < 0) {
> +			dev_err(dev, "rst_gpio request failed: %d\n", err);
> +			return err;
> +		}
> +		err = gpio_direction_output(port->rst_gpio, 0);
> +		if (err < 0) {
> +			dev_err(dev, "rst_gpio set o/p failed: %d\n", err);
> +			return err;
> +		}
> +	}
> +
>  	return 0;
>  }
>  
> -- 
> 2.17.1
> 

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 833 bytes --]

  reply index

Thread overview: 106+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-04-11 17:03 [PATCH 00/30] Enable Tegra PCIe root port features Manikanta Maddireddy
2019-04-11 17:03 ` [PATCH 01/30] soc/tegra: pmc: Export tegra_powergate_power_on() Manikanta Maddireddy
2019-04-11 17:03 ` [PATCH 02/30] PCI: tegra: Fix PCIe host power up sequence Manikanta Maddireddy
2019-04-15 11:01   ` Thierry Reding
2019-04-15 14:11     ` Manikanta Maddireddy
2019-04-15 14:30       ` Thierry Reding
2019-04-15 18:14         ` Manikanta Maddireddy
2019-04-11 17:03 ` [PATCH 03/30] PCI: tegra: Move REFCLK pad settings out of phy_power_on() Manikanta Maddireddy
2019-04-15 11:06   ` Thierry Reding
2019-04-15 14:20     ` Manikanta Maddireddy
2019-04-11 17:03 ` [PATCH 04/30] PCI: tegra: Add PCIe Gen2 link speed support Manikanta Maddireddy
2019-04-15 11:21   ` Thierry Reding
2019-04-15 14:47     ` Manikanta Maddireddy
2019-04-15 15:36       ` Thierry Reding
2019-04-15 15:53         ` Manikanta Maddireddy
2019-04-11 17:03 ` [PATCH 05/30] PCI: tegra: Advertise PCIe Advanced Error Reporting (AER) capability Manikanta Maddireddy
2019-04-15 11:23   ` Thierry Reding
2019-04-15 14:49     ` Manikanta Maddireddy
2019-04-11 17:03 ` [PATCH 06/30] PCI: tegra: Program UPHY electrical settings for Tegra210 Manikanta Maddireddy
2019-04-15 11:29   ` Thierry Reding
2019-04-15 14:55     ` Manikanta Maddireddy
2019-04-15 15:38       ` Thierry Reding
2019-04-11 17:03 ` [PATCH 07/30] PCI: tegra: Enable opportunistic update FC and ACK Manikanta Maddireddy
2019-04-15 11:30   ` Thierry Reding
2019-04-11 17:03 ` [PATCH 08/30] PCI: tegra: Disable AFI dynamic clock gating Manikanta Maddireddy
2019-04-15 11:32   ` Thierry Reding
2019-04-11 17:03 ` [PATCH 09/30] PCI: tegra: Process pending DLL transactions before entering L1 or L2 Manikanta Maddireddy
2019-04-15 11:33   ` Thierry Reding
2019-04-11 17:03 ` [PATCH 10/30] PCI: tegra: Enable PCIe xclk clock clamping Manikanta Maddireddy
2019-04-15 11:37   ` Thierry Reding
2019-04-15 14:58     ` Manikanta Maddireddy
2019-04-11 17:03 ` [PATCH 11/30] PCI: tegra: Increase the deskew retry time Manikanta Maddireddy
2019-04-15 11:39   ` Thierry Reding
2019-04-15 14:58     ` Manikanta Maddireddy
2019-04-11 17:03 ` [PATCH 12/30] PCI: tegra: Add SW fixup for RAW violations Manikanta Maddireddy
2019-04-11 20:01   ` Bjorn Helgaas
2019-04-12  5:59     ` Manikanta Maddireddy
2019-04-15 11:41       ` Thierry Reding
2019-04-15 11:45   ` Thierry Reding
2019-04-15 15:02     ` Manikanta Maddireddy
2019-04-11 17:03 ` [PATCH 13/30] PCI: tegra: Update flow control threshold in Tegra210 Manikanta Maddireddy
2019-04-15 11:47   ` Thierry Reding
2019-04-15 15:05     ` Manikanta Maddireddy
2019-04-23  9:27       ` Manikanta Maddireddy
2019-04-11 17:03 ` [PATCH 14/30] PCI: tegra: Set target speed as Gen1 before link up Manikanta Maddireddy
2019-04-11 20:04   ` Bjorn Helgaas
2019-04-12  6:44     ` Manikanta Maddireddy
2019-04-12 14:35       ` Bjorn Helgaas
2019-04-15 10:43         ` Manikanta Maddireddy
2019-04-15 11:52   ` Thierry Reding
2019-04-15 15:12     ` Manikanta Maddireddy
2019-04-11 17:03 ` [PATCH 15/30] PCI: tegra: Fix PLLE powerdown issue due to CLKREQ# signal Manikanta Maddireddy
2019-04-15 13:17   ` Thierry Reding
2019-04-15 15:14     ` Manikanta Maddireddy
2019-04-11 17:03 ` [PATCH 16/30] PCI: tegra: Program AFI_CACHE* registers only for Tegra20 Manikanta Maddireddy
2019-04-15 13:20   ` Thierry Reding
2019-04-16 10:47     ` Manikanta Maddireddy
2019-04-16 16:11       ` Thierry Reding
2019-04-11 17:03 ` [PATCH 17/30] PCI: tegra: Use switch statements in tegra_pcie_isr() Manikanta Maddireddy
2019-04-15 13:25   ` Thierry Reding
2019-04-15 15:25     ` Manikanta Maddireddy
2019-04-11 17:03 ` [PATCH 18/30] PCI: tegra: Change PRSNT_SENSE irq log to debug Manikanta Maddireddy
2019-04-11 17:03 ` [PATCH 19/30] PCI: tegra: Use legacy irq for port service drivers Manikanta Maddireddy
2019-04-15 13:35   ` Thierry Reding
2019-04-11 17:03 ` [PATCH 20/30] PCI: tegra: Add AFI_PEX2_CTRL reg offset as part of soc struct Manikanta Maddireddy
2019-04-15 13:31   ` Thierry Reding
2019-04-11 17:03 ` [PATCH 21/30] PCI: tegra: Add "pci" type check before parsing child device tree node Manikanta Maddireddy
2019-04-15 13:37   ` Thierry Reding
2019-04-15 15:30     ` Manikanta Maddireddy
2019-04-15 15:42       ` Thierry Reding
2019-04-11 17:03 ` [PATCH 22/30] PCI: tegra: Access endpoint config only if PCIe link is up Manikanta Maddireddy
2019-04-11 20:15   ` Bjorn Helgaas
2019-04-12  7:00     ` Manikanta Maddireddy
2019-04-12 14:50       ` Bjorn Helgaas
2019-04-15 11:36         ` Manikanta Maddireddy
2019-04-15 13:45           ` Thierry Reding
2019-04-15 13:52             ` Thierry Reding
2019-04-15 14:04           ` Bjorn Helgaas
2019-04-15 15:43             ` Manikanta Maddireddy
2019-04-23 20:24               ` Bjorn Helgaas
2019-04-11 17:03 ` [PATCH 23/30] dt-bindings: pci: tegra: Document PCIe DPD pinctrl optional prop Manikanta Maddireddy
2019-04-15 14:07   ` Thierry Reding
2019-04-15 15:48     ` Manikanta Maddireddy
2019-04-11 17:03 ` [PATCH 24/30] arm64: tegra: Add PEX DPD states as pinctrl properties Manikanta Maddireddy
2019-04-11 17:03 ` [PATCH 25/30] PCI: tegra: Put PEX CLK & BIAS pads in DPD mode Manikanta Maddireddy
2019-04-15 14:11   ` Thierry Reding
2019-04-11 17:03 ` [PATCH 26/30] dt-bindings: pci: tegra: Document nvidia,plat-gpios optional prop Manikanta Maddireddy
2019-04-11 20:18   ` Bjorn Helgaas
2019-04-12  7:01     ` Manikanta Maddireddy
2019-04-15 14:16   ` Thierry Reding
2019-04-15 17:58     ` Manikanta Maddireddy
2019-04-16 15:34       ` Thierry Reding
2019-04-17 11:22         ` Manikanta Maddireddy
2019-04-17 15:19           ` Thierry Reding
2019-04-17 18:26             ` Manikanta Maddireddy
2019-04-11 17:03 ` [PATCH 27/30] PCI: tegra: Add support to configure platform GPIOs Manikanta Maddireddy
2019-04-11 17:03 ` [PATCH 28/30] dt-bindings: pci: tegra: Document nvidia,rst-gpio optional prop Manikanta Maddireddy
2019-04-15 14:20   ` Thierry Reding
2019-04-15 18:01     ` Manikanta Maddireddy
2019-04-29 18:33     ` Rob Herring
2019-04-11 17:03 ` [PATCH 29/30] PCI: tegra: Add support for GPIO based PCIe reset Manikanta Maddireddy
2019-04-15 14:20   ` Thierry Reding [this message]
2019-04-15 18:03     ` Manikanta Maddireddy
2019-04-11 17:03 ` [PATCH 30/30] PCI: tegra: Change link retry log level to INFO Manikanta Maddireddy
2019-04-15 14:23   ` Thierry Reding
2019-04-15 18:05     ` Manikanta Maddireddy

Reply instructions:

You may reply publically to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20190415142058.GC29254@ulmo \
    --to=thierry.reding@gmail.com \
    --cc=bhelgaas@google.com \
    --cc=devicetree@vger.kernel.org \
    --cc=jonathanh@nvidia.com \
    --cc=linux-pci@vger.kernel.org \
    --cc=linux-tegra@vger.kernel.org \
    --cc=lorenzo.pieralisi@arm.com \
    --cc=mark.rutland@arm.com \
    --cc=mmaddireddy@nvidia.com \
    --cc=robh+dt@kernel.org \
    --cc=vidyas@nvidia.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

Linux-PCI Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-pci/0 linux-pci/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-pci linux-pci/ https://lore.kernel.org/linux-pci \
		linux-pci@vger.kernel.org linux-pci@archiver.kernel.org
	public-inbox-index linux-pci


Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-pci


AGPL code for this site: git clone https://public-inbox.org/ public-inbox