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

From: Mohit KUMAR DCG
Date: Thu Mar 27 2014 - 07:55:02 EST


Hello Kishon,

> -----Original Message-----
> From: Jingoo Han [mailto:jg1.han@xxxxxxxxxxx]
> Sent: Thursday, March 27, 2014 5:15 PM
> To: 'Kishon Vijay Abraham I'; Mohit KUMAR DCG; Pratyush ANAND
> Cc: devicetree@xxxxxxxxxxxxxxx; linux-doc@xxxxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linux-
> omap@xxxxxxxxxxxxxxx; linux-pci@xxxxxxxxxxxxxxx; bhelgaas@xxxxxxxxxx;
> robh+dt@xxxxxxxxxx; pawel.moll@xxxxxxx; mark.rutland@xxxxxxx;
> ijc+devicetree@xxxxxxxxxxxxxx; galak@xxxxxxxxxxxxxx; rob@xxxxxxxxxxx;
> linux@xxxxxxxxxxxxxxxx; tony@xxxxxxxxxxx; rnayak@xxxxxx;
> paul@xxxxxxxxx; '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@xxxxxx>
>
> (+cc Pratyush Anand, Marek Vasut, Richard Zhu)
>
> Acked-by: Jingoo Han <jg1.han@xxxxxxxxxxx>
>
> 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@xxxxxx>

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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