On Wed, May 20, 2020 at 9:44 AM Nicolas Saenz Julienne
<nsaenzjulienne@xxxxxxx> wrote:
>
> On Tue, 2020-05-19 at 16:34 -0400, Jim Quinlan wrote:
> > From: Jim Quinlan <jquinlan@xxxxxxxxxxxx>
> >
> > The proper value of the parameter SCB_MAX_BURST_SIZE varies
> > per chip. The 2711 family requires 128B whereas other devices
> > can employ 512. The assignment is complicated by the fact
> > that the values for this two-bit field have different meanings;
> >
> > Value Type_Generic Type_7278
> >
> > 00 Reserved 128B
> > 01 128B 256B
> > 10 256B 512B
> > 11 512B Reserved
> >
> > Signed-off-by: Jim Quinlan <jquinlan@xxxxxxxxxxxx>
> > ---
> > drivers/pci/controller/pcie-brcmstb.c | 18 +++++++++++++++---
> > 1 file changed, 15 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/pci/controller/pcie-brcmstb.c
> > b/drivers/pci/controller/pcie-brcmstb.c
> > index 7bf945efd71b..0dfa1bbd9764 100644
> > --- a/drivers/pci/controller/pcie-brcmstb.c
> > +++ b/drivers/pci/controller/pcie-brcmstb.c
> > @@ -53,7 +53,7 @@
> > #define PCIE_MISC_MISC_CTRL_SCB_ACCESS_EN_MASK 0x1000
> > #define PCIE_MISC_MISC_CTRL_CFG_READ_UR_MODE_MASK 0x2000
> > #define PCIE_MISC_MISC_CTRL_MAX_BURST_SIZE_MASK 0x300000
> > -#define PCIE_MISC_MISC_CTRL_MAX_BURST_SIZE_128 0x0
> > +
> > #define PCIE_MISC_MISC_CTRL_SCB0_SIZE_MASK 0xf8000000
> > #define PCIE_MISC_MISC_CTRL_SCB1_SIZE_MASK 0x07c00000
> > #define PCIE_MISC_MISC_CTRL_SCB2_SIZE_MASK 0x0000001f
> > @@ -276,6 +276,7 @@ struct brcm_pcie {
> > int num_memc;
> > u64 memc_size[PCIE_BRCM_MAX_MEMC];
> > u32 hw_rev;
> > + const struct of_device_id *of_id;
> > };
> >
> > /*
> > @@ -841,7 +842,7 @@ static int brcm_pcie_setup(struct brcm_pcie *pcie)
> > int num_out_wins = 0;
> > u16 nlw, cls, lnksta;
> > int i, ret, memc;
> > - u32 tmp, aspm_support;
> > + u32 tmp, burst, aspm_support;
> >
> > /* Reset the bridge */
> > brcm_pcie_bridge_sw_init_set(pcie, 1);
> > @@ -857,10 +858,20 @@ static int brcm_pcie_setup(struct brcm_pcie *pcie)
> > /* Wait for SerDes to be stable */
> > usleep_range(100, 200);
> >
> > + /*
> > + * SCB_MAX_BURST_SIZE is a two bit field. For GENERIC chips it
> > + * is encoded as 0=128, 1=256, 2=512, 3=Rsvd, for BCM7278 it
> > + * is encoded as 0=Rsvd, 1=128, 2=256, 3=512.
> > + */
> > + if (strcmp(pcie->of_id->compatible, "brcm,bcm2711-pcie") == 0)
>
> Would it make sense to use pcie->type here? I know GENERIC != BCM2711, but we
> could define it and avoid adding redundant info in struct brcm_pcie.
Yes, that would get rid of the need for keeping of_id around.
Thanks,
Jim
>
> Regards,
> Nicolas
>
> > + burst = 0x0; /* 128B */
> > + else
> > + burst = (pcie->type == BCM7278) ? 0x3 : 0x2; /* 512 bytes */
> > +
> > /* Set SCB_MAX_BURST_SIZE, CFG_READ_UR_MODE, SCB_ACCESS_EN */
> > u32p_replace_bits(&tmp, 1, PCIE_MISC_MISC_CTRL_SCB_ACCESS_EN_MASK);
> > u32p_replace_bits(&tmp, 1, PCIE_MISC_MISC_CTRL_CFG_READ_UR_MODE_MASK);
> > - u32p_replace_bits(&tmp, PCIE_MISC_MISC_CTRL_MAX_BURST_SIZE_128,
> > + u32p_replace_bits(&tmp, burst,
> > PCIE_MISC_MISC_CTRL_MAX_BURST_SIZE_MASK);
> > writel(tmp, base + PCIE_MISC_MISC_CTRL);
> >
> > @@ -1200,6 +1211,7 @@ static int brcm_pcie_probe(struct platform_device *pdev)
> > pcie->reg_offsets = data->offsets;
> > pcie->reg_field_info = data->reg_field_info;
> > pcie->type = data->type;
> > + pcie->of_id = of_id;
> >
> > res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > pcie->base = devm_ioremap_resource(&pdev->dev, res);
>
