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@chromium.org ---
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 + * @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), +};