[PATCH] pci: pci_mvebu: Add support for reset-gpios

[Pali Rohár]

On Friday 05 August 2022 13:48:36 Stefan Roese wrote:
> On 05.08.22 13:45, Pali Rohár wrote:
> > On Friday 05 August 2022 13:01:27 Stefan Roese wrote:
> > > On 28.07.22 15:03, Pali Rohár wrote:
> > > > Release PERST# signal via GPIO when "reset-gpios" is defined in device tree.
> > > > 
> > > > Signed-off-by: Pali Rohár <pali at kernel.org>
> > > > ---
> > > >    drivers/pci/pci_mvebu.c | 14 ++++++++++++++
> > > >    1 file changed, 14 insertions(+)
> > > > 
> > > > diff --git a/drivers/pci/pci_mvebu.c b/drivers/pci/pci_mvebu.c
> > > > index d80f87e0cfc6..269c027db204 100644
> > > > --- a/drivers/pci/pci_mvebu.c
> > > > +++ b/drivers/pci/pci_mvebu.c
> > > > @@ -22,6 +22,7 @@
> > > >    #include <asm/io.h>
> > > >    #include <asm/arch/cpu.h>
> > > >    #include <asm/arch/soc.h>
> > > > +#include <asm-generic/gpio.h>
> > > >    #include <linux/bitops.h>
> > > >    #include <linux/delay.h>
> > > >    #include <linux/errno.h>
> > > > @@ -60,6 +61,7 @@ struct mvebu_pcie {
> > > >    	struct resource mem;
> > > >    	void __iomem *iobase;
> > > >    	struct resource io;
> > > > +	struct gpio_desc reset_gpio;
> > > >    	u32 intregs;
> > > >    	u32 port;
> > > >    	u32 lane;
> > > > @@ -416,6 +418,14 @@ static int mvebu_pcie_probe(struct udevice *dev)
> > > >    	struct udevice *ctlr = pci_get_controller(dev);
> > > >    	struct pci_controller *hose = dev_get_uclass_priv(ctlr);
> > > >    	u32 reg;
> > > > +	int ret;
> > > > +
> > > > +	/* Request for optional PERST# GPIO */
> > > > +	ret = gpio_request_by_name(dev, "reset-gpios", 0, &pcie->reset_gpio, GPIOD_IS_OUT);
> > > > +	if (ret && ret != -ENOENT) {
> > > > +		printf("%s: unable to request reset-gpios: %d\n", pcie->name, ret);
> > > > +		return ret;
> > > > +	}
> > > >    	/*
> > > >    	 * Change Class Code of PCI Bridge device to PCI Bridge (0x600400)
> > > > @@ -537,6 +547,10 @@ static int mvebu_pcie_probe(struct udevice *dev)
> > > >    	pcie->cfgcache[(PCI_PREF_MEMORY_BASE - 0x10) / 4] =
> > > >    		PCI_PREF_RANGE_TYPE_64 | (PCI_PREF_RANGE_TYPE_64 << 16);
> > > > +	/* Release PERST# via GPIO when it was defined */
> > > > +	if (dm_gpio_is_valid(&pcie->reset_gpio))
> > > > +		dm_gpio_set_value(&pcie->reset_gpio, 0);
> > > > +
> > > >    	mvebu_pcie_wait_for_link(pcie);
> > > >    	return 0;
> > > 
> > > While running some build tests, this error shows on some Kirkwood
> > > boards:
> > > 
> > > $ make pogo_v4_defconfig
> > > $ make -s -j20
> > > ===================== WARNING ======================
> > > This board does not use CONFIG_TIMER (Driver Model
> > > for Timer drivers). Please update the board to use
> > > CONFIG_TIMER before the v2023.01 release. Failure to
> > > update by the deadline may result in board removal.
> > > See doc/develop/driver-model/migration.rst for more info.
> > > ====================================================
> > > ===================== WARNING ======================
> > > This board does not use CONFIG_DM_SERIAL (Driver Model
> > > for Serial drivers). Please update the board to use
> > > CONFIG_DM_SERIAL before the v2023.04 release. Failure to
> > > update by the deadline may result in board removal.
> > > See doc/develop/driver-model/migration.rst for more info.
> > > ====================================================
> > > /opt/kernel.org/gcc-11.1.0-nolibc/arm-linux-gnueabi/bin/arm-linux-gnueabi-ld.bfd:
> > > drivers/pci/pci_mvebu.o: in function `mvebu_pcie_probe':
> > > /home/stefan/git/u-boot/u-boot-marvell/drivers/pci/pci_mvebu.c:424:
> > > undefined reference to `gpio_request_by_name'
> > > /opt/kernel.org/gcc-11.1.0-nolibc/arm-linux-gnueabi/bin/arm-linux-gnueabi-ld.bfd:
> > > /home/stefan/git/u-boot/u-boot-marvell/drivers/pci/pci_mvebu.c:552:
> > > undefined reference to `dm_gpio_set_value'
> > > make: *** [Makefile:1818: u-boot] Error 1
> > > 
> > > Could you please take a look and make sure, that world build succeeds?
> > > 
> > > Thanks,
> > > Stefan
> > 
> > There is probably missing DM_GPIO. Now I started CI test on github:
> > https://github.com/u-boot/u-boot/pull/204
> > After that I will send v2.
> 
> Perfect. Thanks.
> 
> Thanks,
> Stefan

CI tests passed, now sending v2.