[U-Boot] [PATCH v5 089/101] x86: apl: Add hostbridge driver
Bin Meng
bmeng.cn at gmail.com
Mon Dec 2 07:31:09 CET 2019
Hi Simon,
On Mon, Nov 25, 2019 at 12:12 PM Simon Glass <sjg at chromium.org> wrote:
>
> This driver models the hostbridge as a northbridge. It simply sets up the
> graphics BAR. It supports of-platdata.
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
>
> Changes in v5: None
> Changes in v4:
> - Avoid needing to know internals of pinctrl in this driver
> - Move code to pinctrl driver
> - Switch over to use pinctrl for pad init/config
>
> Changes in v3:
> - Move pad programming into the hostbridge to reduce TPL device-tree size
> - Use pci_get_devfn()
>
> Changes in v2: None
>
> arch/x86/cpu/apollolake/Makefile | 1 +
> arch/x86/cpu/apollolake/hostbridge.c | 179 +++++++++++++++++++++++++++
> 2 files changed, 180 insertions(+)
> create mode 100644 arch/x86/cpu/apollolake/hostbridge.c
>
> diff --git a/arch/x86/cpu/apollolake/Makefile b/arch/x86/cpu/apollolake/Makefile
> index 3a8c2f66a3..4d3c08f84e 100644
> --- a/arch/x86/cpu/apollolake/Makefile
> +++ b/arch/x86/cpu/apollolake/Makefile
> @@ -4,5 +4,6 @@
>
> obj-$(CONFIG_SPL_BUILD) += systemagent.o
>
> +obj-y += hostbridge.o
> obj-y += pmc.o
> obj-y += uart.o
> diff --git a/arch/x86/cpu/apollolake/hostbridge.c b/arch/x86/cpu/apollolake/hostbridge.c
> new file mode 100644
> index 0000000000..25fb51dd9a
> --- /dev/null
> +++ b/arch/x86/cpu/apollolake/hostbridge.c
> @@ -0,0 +1,179 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright 2019 Google LLC
> + */
> +
> +#include <common.h>
> +#include <dm.h>
> +#include <dt-structs.h>
> +#include <spl.h>
> +#include <asm/intel_pinctrl.h>
> +#include <asm/intel_regs.h>
> +#include <asm/pci.h>
> +#include <asm/arch/systemagent.h>
> +
> +/**
> + * struct apl_hostbridge_platdata - platform data for hostbridge
> + *
> + * @num_cfgs: Number of configuration words for each pad
There is no num_cfgs member in this struct
> + * @early_pads: Early pad data to set up, each (pad, cfg0, cfg1)
> + * @early_pads_count: Number of pads to process
> + * @pciex_region_size: BAR length in bytes
> + * @bdf: Bus/device/function of hostbridge
> + */
> +struct apl_hostbridge_platdata {
> +#if CONFIG_IS_ENABLED(OF_PLATDATA)
> + struct dtd_intel_apl_hostbridge dtplat;
> +#endif
> + u32 *early_pads;
> + int early_pads_count;
> + uint pciex_region_size;
> + pci_dev_t bdf;
> +};
> +
> +enum {
> + PCIEXBAR = 0x60,
> + PCIEXBAR_LENGTH_256MB = 0,
> + PCIEXBAR_LENGTH_128MB,
> + PCIEXBAR_LENGTH_64MB,
> +
> + PCIEXBAR_PCIEXBAREN = 1 << 0,
> +
> + TSEG = 0xb8, /* TSEG base */
> +};
> +
> +static int apl_hostbridge_early_init_pinctrl(struct udevice *dev)
> +{
> + struct apl_hostbridge_platdata *plat = dev_get_platdata(dev);
> + struct udevice *pinctrl;
> + int ret;
> +
> + ret = uclass_first_device_err(UCLASS_PINCTRL, &pinctrl);
> + if (ret)
> + return log_msg_ret("no hostbridge pinctrl", ret);
> +
> + return pinctrl_config_pads(pinctrl, plat->early_pads,
> + plat->early_pads_count);
> +}
> +
> +static int apl_hostbridge_early_init(struct udevice *dev)
> +{
> + struct apl_hostbridge_platdata *plat = dev_get_platdata(dev);
> + u32 region_size;
> + ulong base;
> + u32 reg;
> + int ret;
> +
> + /* Set up the MCHBAR */
> + pci_x86_read_config(plat->bdf, MCHBAR, &base, PCI_SIZE_32);
> + base = MCH_BASE_ADDRESS;
> + pci_x86_write_config(plat->bdf, MCHBAR, base | 1, PCI_SIZE_32);
> +
> + /*
> + * The PCIEXBAR is assumed to live in the memory mapped IO space under
> + * 4GiB
> + */
> + pci_x86_write_config(plat->bdf, PCIEXBAR + 4, 0, PCI_SIZE_32);
> +
> + switch (plat->pciex_region_size >> 20) {
> + default:
> + case 256:
> + region_size = PCIEXBAR_LENGTH_256MB;
> + break;
> + case 128:
> + region_size = PCIEXBAR_LENGTH_128MB;
> + break;
> + case 64:
> + region_size = PCIEXBAR_LENGTH_64MB;
> + break;
> + }
> +
> + reg = CONFIG_MMCONF_BASE_ADDRESS | (region_size << 1)
> + | PCIEXBAR_PCIEXBAREN;
> + pci_x86_write_config(plat->bdf, PCIEXBAR, reg, PCI_SIZE_32);
> +
> + /*
> + * TSEG defines the base of SMM range. BIOS determines the base
> + * of TSEG memory which must be at or below Graphics base of GTT
> + * Stolen memory, hence its better to clear TSEG register early
> + * to avoid power on default non-zero value (if any).
> + */
> + pci_x86_write_config(plat->bdf, TSEG, 0, PCI_SIZE_32);
> +
> + ret = apl_hostbridge_early_init_pinctrl(dev);
> + if (ret)
> + return log_msg_ret("pinctrl", ret);
> +
> + return 0;
> +}
> +
> +static int apl_hostbridge_ofdata_to_platdata(struct udevice *dev)
> +{
> + struct apl_hostbridge_platdata *plat = dev_get_platdata(dev);
> + struct udevice *pinctrl;
> + int ret;
> +
> + /*
> + * The host bridge holds the early pad data needed to get through TPL.
> + * This is a small amount of data, enough to fit in TPL, so we keep it
> + * separate from the full pad data, stored in the fsp-s subnode. That
> + * subnode is not present in TPL, to save space.
> + */
> + ret = uclass_first_device_err(UCLASS_PINCTRL, &pinctrl);
> + if (ret)
> + return log_msg_ret("no hostbridge PINCTRL", ret);
> +#if !CONFIG_IS_ENABLED(OF_PLATDATA)
> + int root;
> +
> + /* Get length of PCI Express Region */
> + plat->pciex_region_size = dev_read_u32_default(dev, "pciex-region-size",
> + 256 << 20);
> +
> + root = pci_get_devfn(dev);
> + if (root < 0)
> + return log_msg_ret("Cannot get host-bridge PCI address", root);
> + plat->bdf = root;
> +
> + ret = pinctrl_read_pads(pinctrl, dev_ofnode(dev), "early-pads",
> + &plat->early_pads, &plat->early_pads_count);
> + if (ret)
> + return log_msg_ret("early-pads", ret);
> +#else
> + struct dtd_intel_apl_hostbridge *dtplat = &plat->dtplat;
> + int size;
> +
> + plat->pciex_region_size = dtplat->pciex_region_size;
> + plat->bdf = pci_ofplat_get_devfn(dtplat->reg[0]);
> +
> + /* Assume that if everything is 0, it is empty */
> + plat->early_pads = dtplat->early_pads;
> + size = ARRAY_SIZE(dtplat->early_pads);
> + plat->early_pads_count = pinctrl_count_pads(pinctrl, plat->early_pads,
> + size);
> +
> +#endif
> +
> + return 0;
> +}
> +
> +static int apl_hostbridge_probe(struct udevice *dev)
> +{
> + if (spl_phase() == PHASE_TPL)
> + return apl_hostbridge_early_init(dev);
> +
> + return 0;
> +}
> +
> +static const struct udevice_id apl_hostbridge_ids[] = {
> + { .compatible = "intel,apl-hostbridge" },
> + { }
> +};
> +
> +U_BOOT_DRIVER(apl_hostbridge_drv) = {
> + .name = "intel_apl_hostbridge",
> + .id = UCLASS_NORTHBRIDGE,
> + .of_match = apl_hostbridge_ids,
> + .ofdata_to_platdata = apl_hostbridge_ofdata_to_platdata,
> + .probe = apl_hostbridge_probe,
> + .platdata_auto_alloc_size = sizeof(struct apl_hostbridge_platdata),
> +};
> --
Regards,
Bin
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