[RFC PATCH 03/12] pci: host: pcie-designware: Use *base-mask* for configuring the iATU

Mohit KUMAR DCG Mohit.KUMAR at st.com
Thu Mar 27 07:53:26 EDT 2014


Hello Kishon,

> -----Original Message-----
> From: Jingoo Han [mailto:jg1.han at samsung.com]
> Sent: Thursday, March 27, 2014 5:15 PM
> To: 'Kishon Vijay Abraham I'; Mohit KUMAR DCG; Pratyush ANAND
> Cc: devicetree at vger.kernel.org; linux-doc at vger.kernel.org; linux-
> kernel at vger.kernel.org; linux-arm-kernel at lists.infradead.org; linux-
> omap at vger.kernel.org; linux-pci at vger.kernel.org; bhelgaas at google.com;
> robh+dt at kernel.org; pawel.moll at arm.com; mark.rutland at arm.com;
> ijc+devicetree at hellion.org.uk; galak at codeaurora.org; rob at landley.net;
> linux at arm.linux.org.uk; tony at atomide.com; rnayak at ti.com;
> paul at pwsan.com; 'Marek Vasut'; 'Richard Zhu'
> Subject: Re: [RFC PATCH 03/12] pci: host: pcie-designware: Use *base-mask*
> for configuring the iATU
> 
> On Wednesday, March 26, 2014 10:58 PM, Kishon Vijay Abraham I wrote:
> >
> > In DRA7, the cpu sees 32bit address, but the pcie controller can see
> > only 28bit address. So whenever the cpu issues a read/write request,
> > the 4 most significant bits are used by L3 to determine the target controller.
> > For example, the cpu reserves 0x2000_0000 - 0x2FFF_FFFF for PCIe
> > controller but the PCIe controller will see only (0x000_0000 -
> > 0xFFF_FFF). So for programming the outbound translation window the
> *base* should be programmed as 0x000_0000.
> > Whenever we try to write to say 0x2000_0000, it will be translated to
> > whatever we have programmed in the translation window with base as
> 0x000_0000.
> >
> > Signed-off-by: Kishon Vijay Abraham I <kishon at ti.com>
> 
> (+cc Pratyush Anand, Marek Vasut, Richard Zhu)
> 
> Acked-by: Jingoo Han <jg1.han at samsung.com>
> 
> Mohit Kumar, Pratyush Anand,
> If you have other opinions, please let us know. :-) Thank you.
> 

- Yes, looks more clean now.
Acked-by: Mohit Kumar <mohit.kumar at st.com>

Regards,
Mohit

> Best regards,
> Jingoo Han
> 
> > ---
> >  .../devicetree/bindings/pci/designware-pcie.txt    |    1 +
> >  drivers/pci/host/pcie-designware.c                 |   39 ++++++++++++++------
> >  drivers/pci/host/pcie-designware.h                 |    1 +
> >  3 files changed, 29 insertions(+), 12 deletions(-)
> >
> > diff --git a/Documentation/devicetree/bindings/pci/designware-pcie.txt
> > b/Documentation/devicetree/bindings/pci/designware-pcie.txt
> > index d6fae13..c574dd3 100644
> > --- a/Documentation/devicetree/bindings/pci/designware-pcie.txt
> > +++ b/Documentation/devicetree/bindings/pci/designware-pcie.txt
> > @@ -27,6 +27,7 @@ Optional properties for fsl,imx6q-pcie
> >  - power-on-gpio: gpio pin number of power-enable signal
> >  - wake-up-gpio: gpio pin number of incoming wakeup signal
> >  - disable-gpio: gpio pin number of outgoing rfkill/endpoint disable
> > signal
> > +- base-mask: address mask for the PCIe controller target port
> >
> >  Example:
> >
> > diff --git a/drivers/pci/host/pcie-designware.c
> > b/drivers/pci/host/pcie-designware.c
> > index 17ce88f..98b661c 100644
> > --- a/drivers/pci/host/pcie-designware.c
> > +++ b/drivers/pci/host/pcie-designware.c
> > @@ -464,6 +464,9 @@ int __init dw_pcie_host_init(struct pcie_port *pp)
> >  		return -EINVAL;
> >  	}
> >
> > +	if (of_property_read_u64(np, "base-mask", &pp->base_mask))
> > +		pp->base_mask = ~(0x0ULL);
> > +
> >  	if (IS_ENABLED(CONFIG_PCI_MSI)) {
> >  		pp->irq_domain = irq_domain_add_linear(pp->dev-
> >of_node,
> >  					MAX_MSI_IRQS, &msi_domain_ops,
> > @@ -503,12 +506,15 @@ int __init dw_pcie_host_init(struct pcie_port
> > *pp)
> >
> >  static void dw_pcie_prog_viewport_cfg0(struct pcie_port *pp, u32
> > busdev)  {
> > +	u64 cfg0_base;
> > +
> > +	cfg0_base = pp->cfg0_base & pp->base_mask;
> >  	/* Program viewport 0 : OUTBOUND : CFG0 */
> >  	dw_pcie_writel_rc(pp, PCIE_ATU_REGION_OUTBOUND |
> PCIE_ATU_REGION_INDEX0,
> >  			  PCIE_ATU_VIEWPORT);
> > -	dw_pcie_writel_rc(pp, pp->cfg0_base, PCIE_ATU_LOWER_BASE);
> > -	dw_pcie_writel_rc(pp, (pp->cfg0_base >> 32),
> PCIE_ATU_UPPER_BASE);
> > -	dw_pcie_writel_rc(pp, pp->cfg0_base + pp->config.cfg0_size - 1,
> > +	dw_pcie_writel_rc(pp, cfg0_base, PCIE_ATU_LOWER_BASE);
> > +	dw_pcie_writel_rc(pp, (cfg0_base >> 32), PCIE_ATU_UPPER_BASE);
> > +	dw_pcie_writel_rc(pp, cfg0_base + pp->config.cfg0_size - 1,
> >  			  PCIE_ATU_LIMIT);
> >  	dw_pcie_writel_rc(pp, busdev, PCIE_ATU_LOWER_TARGET);
> >  	dw_pcie_writel_rc(pp, 0, PCIE_ATU_UPPER_TARGET); @@ -518,14
> +524,17
> > @@ static void dw_pcie_prog_viewport_cfg0(struct pcie_port *pp, u32
> > busdev)
> >
> >  static void dw_pcie_prog_viewport_cfg1(struct pcie_port *pp, u32
> > busdev)  {
> > +	u64 cfg1_base;
> > +
> > +	cfg1_base = pp->cfg1_base & pp->base_mask;
> >  	/* Program viewport 1 : OUTBOUND : CFG1 */
> >  	dw_pcie_writel_rc(pp, PCIE_ATU_REGION_OUTBOUND |
> PCIE_ATU_REGION_INDEX1,
> >  			  PCIE_ATU_VIEWPORT);
> >  	dw_pcie_writel_rc(pp, PCIE_ATU_TYPE_CFG1, PCIE_ATU_CR1);
> >  	dw_pcie_writel_rc(pp, PCIE_ATU_ENABLE, PCIE_ATU_CR2);
> > -	dw_pcie_writel_rc(pp, pp->cfg1_base, PCIE_ATU_LOWER_BASE);
> > -	dw_pcie_writel_rc(pp, (pp->cfg1_base >> 32),
> PCIE_ATU_UPPER_BASE);
> > -	dw_pcie_writel_rc(pp, pp->cfg1_base + pp->config.cfg1_size - 1,
> > +	dw_pcie_writel_rc(pp, cfg1_base, PCIE_ATU_LOWER_BASE);
> > +	dw_pcie_writel_rc(pp, (cfg1_base >> 32), PCIE_ATU_UPPER_BASE);
> > +	dw_pcie_writel_rc(pp, cfg1_base + pp->config.cfg1_size - 1,
> >  			  PCIE_ATU_LIMIT);
> >  	dw_pcie_writel_rc(pp, busdev, PCIE_ATU_LOWER_TARGET);
> >  	dw_pcie_writel_rc(pp, 0, PCIE_ATU_UPPER_TARGET); @@ -533,14
> +542,17
> > @@ static void dw_pcie_prog_viewport_cfg1(struct pcie_port *pp, u32
> > busdev)
> >
> >  static void dw_pcie_prog_viewport_mem_outbound(struct pcie_port
> *pp)
> > {
> > +	u64 mem_base;
> > +
> > +	mem_base = pp->mem_base & pp->base_mask;
> >  	/* Program viewport 0 : OUTBOUND : MEM */
> >  	dw_pcie_writel_rc(pp, PCIE_ATU_REGION_OUTBOUND |
> PCIE_ATU_REGION_INDEX0,
> >  			  PCIE_ATU_VIEWPORT);
> >  	dw_pcie_writel_rc(pp, PCIE_ATU_TYPE_MEM, PCIE_ATU_CR1);
> >  	dw_pcie_writel_rc(pp, PCIE_ATU_ENABLE, PCIE_ATU_CR2);
> > -	dw_pcie_writel_rc(pp, pp->mem_base, PCIE_ATU_LOWER_BASE);
> > -	dw_pcie_writel_rc(pp, (pp->mem_base >> 32),
> PCIE_ATU_UPPER_BASE);
> > -	dw_pcie_writel_rc(pp, pp->mem_base + pp->config.mem_size - 1,
> > +	dw_pcie_writel_rc(pp, mem_base, PCIE_ATU_LOWER_BASE);
> > +	dw_pcie_writel_rc(pp, (mem_base >> 32), PCIE_ATU_UPPER_BASE);
> > +	dw_pcie_writel_rc(pp, mem_base + pp->config.mem_size - 1,
> >  			  PCIE_ATU_LIMIT);
> >  	dw_pcie_writel_rc(pp, pp->config.mem_bus_addr,
> PCIE_ATU_LOWER_TARGET);
> >  	dw_pcie_writel_rc(pp, upper_32_bits(pp->config.mem_bus_addr),
> > @@ -549,14 +561,17 @@ static void
> > dw_pcie_prog_viewport_mem_outbound(struct pcie_port *pp)
> >
> >  static void dw_pcie_prog_viewport_io_outbound(struct pcie_port *pp)
> > {
> > +	u64 io_base;
> > +
> > +	io_base = pp->io_base & pp->base_mask;
> >  	/* Program viewport 1 : OUTBOUND : IO */
> >  	dw_pcie_writel_rc(pp, PCIE_ATU_REGION_OUTBOUND |
> PCIE_ATU_REGION_INDEX1,
> >  			  PCIE_ATU_VIEWPORT);
> >  	dw_pcie_writel_rc(pp, PCIE_ATU_TYPE_IO, PCIE_ATU_CR1);
> >  	dw_pcie_writel_rc(pp, PCIE_ATU_ENABLE, PCIE_ATU_CR2);
> > -	dw_pcie_writel_rc(pp, pp->io_base, PCIE_ATU_LOWER_BASE);
> > -	dw_pcie_writel_rc(pp, (pp->io_base >> 32),
> PCIE_ATU_UPPER_BASE);
> > -	dw_pcie_writel_rc(pp, pp->io_base + pp->config.io_size - 1,
> > +	dw_pcie_writel_rc(pp, io_base, PCIE_ATU_LOWER_BASE);
> > +	dw_pcie_writel_rc(pp, (io_base >> 32), PCIE_ATU_UPPER_BASE);
> > +	dw_pcie_writel_rc(pp, io_base + pp->config.io_size - 1,
> >  			  PCIE_ATU_LIMIT);
> >  	dw_pcie_writel_rc(pp, pp->config.io_bus_addr,
> PCIE_ATU_LOWER_TARGET);
> >  	dw_pcie_writel_rc(pp, upper_32_bits(pp->config.io_bus_addr),
> > diff --git a/drivers/pci/host/pcie-designware.h
> > b/drivers/pci/host/pcie-designware.h
> > index 3063b35..3fa12a6 100644
> > --- a/drivers/pci/host/pcie-designware.h
> > +++ b/drivers/pci/host/pcie-designware.h
> > @@ -35,6 +35,7 @@ struct pcie_port {
> >  	struct device		*dev;
> >  	u8			root_bus_nr;
> >  	void __iomem		*dbi_base;
> > +	u64			base_mask;
> >  	u64			cfg0_base;
> >  	void __iomem		*va_cfg0_base;
> >  	u64			cfg1_base;
> > --
> > 1.7.9.5




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