[U-Boot] [PATCH v5 097/101] x86: apl: Add P2SB driver

Bin Meng bmeng.cn at gmail.com
Mon Dec 2 08:33:51 CET 2019


On Mon, Nov 25, 2019 at 12:12 PM Simon Glass <sjg at chromium.org> wrote:
>
> Adds a driver for the Apollo Lake Primary-to-sideband bus. This supports
> various child devices. It supposed both device tree and of-platdata.
>
> Signed-off-by: Simon Glass <sjg at chromium.org>
> ---
>
> Changes in v5: None
> Changes in v4:
> - Detect zero mmio address
> - Use BIT() macro bit more
> - apollolake -> Apollo Lake
>
> Changes in v3:
> - Use pci_get_devfn()
>
> Changes in v2: None
>
>  arch/x86/cpu/apollolake/Makefile |   1 +
>  arch/x86/cpu/apollolake/p2sb.c   | 167 +++++++++++++++++++++++++++++++
>  2 files changed, 168 insertions(+)
>  create mode 100644 arch/x86/cpu/apollolake/p2sb.c
>
> diff --git a/arch/x86/cpu/apollolake/Makefile b/arch/x86/cpu/apollolake/Makefile
> index edde122f75..dc6df15dab 100644
> --- a/arch/x86/cpu/apollolake/Makefile
> +++ b/arch/x86/cpu/apollolake/Makefile
> @@ -15,6 +15,7 @@ endif
>  obj-y += hostbridge.o
>  obj-y += itss.o
>  obj-y += lpc.o
> +obj-y += p2sb.o
>  obj-y += pch.o
>  obj-y += pmc.o
>  obj-y += uart.o
> diff --git a/arch/x86/cpu/apollolake/p2sb.c b/arch/x86/cpu/apollolake/p2sb.c
> new file mode 100644
> index 0000000000..0a5deaf4a0
> --- /dev/null
> +++ b/arch/x86/cpu/apollolake/p2sb.c
> @@ -0,0 +1,167 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Primary-to-Sideband Bridge
> + *
> + * Copyright 2019 Google LLC
> + */
> +
> +#define LOG_CATEGORY UCLASS_P2SB
> +
> +#include <common.h>
> +#include <dm.h>
> +#include <dt-structs.h>
> +#include <p2sb.h>
> +#include <spl.h>
> +#include <asm/pci.h>
> +
> +struct p2sb_platdata {
> +#if CONFIG_IS_ENABLED(OF_PLATDATA)
> +       struct dtd_intel_apl_p2sb dtplat;
> +#endif
> +       ulong mmio_base;
> +       pci_dev_t bdf;
> +};
> +
> +/* PCI config space registers */
> +#define HPTC_OFFSET            0x60
> +#define HPTC_ADDR_ENABLE_BIT   BIT(7)
> +
> +/* High Performance Event Timer Configuration */
> +#define P2SB_HPTC                              0x60
> +#define P2SB_HPTC_ADDRESS_ENABLE               BIT(7)
> +
> +/*
> + * ADDRESS_SELECT            ENCODING_RANGE
> + *      0                 0xfed0 0000 - 0xfed0 03ff
> + *      1                 0xfed0 1000 - 0xfed0 13ff
> + *      2                 0xfed0 2000 - 0xfed0 23ff
> + *      3                 0xfed0 3000 - 0xfed0 33ff
> + */
> +#define P2SB_HPTC_ADDRESS_SELECT_0             (0 << 0)
> +#define P2SB_HPTC_ADDRESS_SELECT_1             (1 << 0)
> +#define P2SB_HPTC_ADDRESS_SELECT_2             (2 << 0)
> +#define P2SB_HPTC_ADDRESS_SELECT_3             (3 << 0)
> +
> +/*
> + * apl_p2sb_early_init() - Enable decoding for HPET range
> + *
> + * This is needed for FspMemoryInit to store and retrieve a global data
> + * pointer

Need more comments, why global data pointer has something to do with HPET?

> + *
> + * @dev: P2SB device
> + * @return 0 if OK, -ve on error
> + */
> +static int apl_p2sb_early_init(struct udevice *dev)
> +{
> +       struct p2sb_platdata *plat = dev_get_platdata(dev);
> +       pci_dev_t pdev = plat->bdf;
> +
> +       /*
> +        * Enable decoding for HPET memory address range.
> +        * HPTC_OFFSET(0x60) bit 7, when set the P2SB will decode
> +        * the High Performance Timer memory address range
> +        * selected by bits 1:0
> +        */
> +       pci_x86_write_config(pdev, HPTC_OFFSET, HPTC_ADDR_ENABLE_BIT,
> +                            PCI_SIZE_8);
> +
> +       /* Enable PCR Base address in PCH */
> +       pci_x86_write_config(pdev, PCI_BASE_ADDRESS_0, plat->mmio_base,
> +                            PCI_SIZE_32);
> +       pci_x86_write_config(pdev, PCI_BASE_ADDRESS_1, 0, PCI_SIZE_32);
> +
> +       /* Enable P2SB MSE */
> +       pci_x86_write_config(pdev, PCI_COMMAND, PCI_COMMAND_MASTER |
> +                            PCI_COMMAND_MEMORY, PCI_SIZE_8);
> +
> +       return 0;
> +}
> +
> +static int apl_p2sb_spl_init(struct udevice *dev)
> +{
> +       /* Enable decoding for HPET. Needed for FSP global pointer storage */
> +       dm_pci_write_config(dev, P2SB_HPTC, P2SB_HPTC_ADDRESS_SELECT_0 |
> +                           P2SB_HPTC_ADDRESS_ENABLE, PCI_SIZE_8);
> +
> +       return 0;
> +}
> +
> +int apl_p2sb_ofdata_to_platdata(struct udevice *dev)
> +{
> +       struct p2sb_uc_priv *upriv = dev_get_uclass_priv(dev);
> +       struct p2sb_platdata *plat = dev_get_platdata(dev);
> +
> +#if !CONFIG_IS_ENABLED(OF_PLATDATA)
> +       int ret;
> +
> +       if (spl_phase() == PHASE_TPL) {
> +               u32 base[2];
> +
> +               /* TPL sets up the initial BAR */
> +               ret = dev_read_u32_array(dev, "early-regs", base,
> +                                        ARRAY_SIZE(base));
> +               if (ret)
> +                       return log_msg_ret("Missing/short early-regs", ret);
> +               plat->mmio_base = base[0];
> +               plat->bdf = pci_get_devfn(dev);
> +               if (plat->bdf < 0)
> +                       return log_msg_ret("Cannot get p2sb PCI address",
> +                                          plat->bdf);
> +       } else {
> +               plat->mmio_base = dev_read_addr_pci(dev);
> +               /* Don't set BDF since it should not be used */
> +               if (!plat->mmio_base || plat->mmio_base == FDT_ADDR_T_NONE)
> +                       return -EINVAL;
> +       }
> +#else
> +       plat->mmio_base = plat->dtplat.early_regs[0];
> +       plat->bdf = pci_ofplat_get_devfn(plat->dtplat.reg[0]);
> +#endif
> +       upriv->mmio_base = plat->mmio_base;
> +       debug("p2sb: mmio_base=%x\n", (uint)plat->mmio_base);
> +
> +       return 0;
> +}
> +
> +static int apl_p2sb_probe(struct udevice *dev)
> +{
> +       if (spl_phase() == PHASE_TPL)
> +               return apl_p2sb_early_init(dev);
> +       else if (spl_phase() == PHASE_SPL)
> +               return apl_p2sb_spl_init(dev);
> +
> +       return 0;
> +}
> +
> +static int p2sb_child_post_bind(struct udevice *dev)
> +{
> +#if !CONFIG_IS_ENABLED(OF_PLATDATA)
> +       struct p2sb_child_platdata *pplat = dev_get_parent_platdata(dev);
> +       int ret;
> +       u32 pid;
> +
> +       ret = dev_read_u32(dev, "intel,p2sb-port-id", &pid);
> +       if (ret)
> +               return ret;
> +       pplat->pid = pid;
> +#endif
> +
> +       return 0;
> +}
> +
> +static const struct udevice_id apl_p2sb_ids[] = {
> +       { .compatible = "intel,apl-p2sb" },
> +       { }
> +};
> +
> +U_BOOT_DRIVER(apl_p2sb_drv) = {
> +       .name           = "intel_apl_p2sb",
> +       .id             = UCLASS_P2SB,
> +       .of_match       = apl_p2sb_ids,
> +       .probe          = apl_p2sb_probe,
> +       .ofdata_to_platdata = apl_p2sb_ofdata_to_platdata,
> +       .platdata_auto_alloc_size = sizeof(struct p2sb_platdata),
> +       .per_child_platdata_auto_alloc_size =
> +               sizeof(struct p2sb_child_platdata),
> +       .child_post_bind = p2sb_child_post_bind,
> +};
> --

Regards,
Bin


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