Add a driver for the Apollo Lake P-unit (power unit). It is modelled as a syscon driver since it only needs to be probed.
Signed-off-by: Simon Glass sjg@chromium.org ---
Changes in v4: - Name this P-Unit instead of power unit, in the commit message - apollolake -> Apollo Lake
Changes in v3: - Use pci_get_devfn()
Changes in v2: None
arch/x86/cpu/apollolake/Makefile | 3 + arch/x86/cpu/apollolake/punit.c | 121 +++++++++++++++++++++++++++++++ 2 files changed, 124 insertions(+) create mode 100644 arch/x86/cpu/apollolake/punit.c
diff --git a/arch/x86/cpu/apollolake/Makefile b/arch/x86/cpu/apollolake/Makefile index 36eefcbad7..875d454157 100644 --- a/arch/x86/cpu/apollolake/Makefile +++ b/arch/x86/cpu/apollolake/Makefile @@ -3,6 +3,9 @@ # Copyright 2019 Google LLC
obj-$(CONFIG_SPL_BUILD) += systemagent.o +ifndef CONFIG_TPL_BUILD +obj-y += punit.o +endif
obj-y += hostbridge.o obj-y += itss.o diff --git a/arch/x86/cpu/apollolake/punit.c b/arch/x86/cpu/apollolake/punit.c new file mode 100644 index 0000000000..3bef4686eb --- /dev/null +++ b/arch/x86/cpu/apollolake/punit.c @@ -0,0 +1,121 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2019 Google LLC + */ + +#include <common.h> +#include <dm.h> +#include <spl.h> +#include <asm/cpu.h> +#include <asm/cpu_common.h> +#include <asm/intel_regs.h> +#include <asm/io.h> +#include <asm/pci.h> +#include <asm/arch/systemagent.h> + +/** + * struct apl_punit_platdata - platform data for punit + * + * @pciex_region_size: BAR length in bytes + */ +struct apl_punit_platdata { + pci_dev_t bdf; +}; + +/* + * Punit Initialization code. This all isn't documented, but + * this is the recipe. + */ +static int punit_init(struct udevice *dev) +{ + struct apl_punit_platdata *plat = dev_get_platdata(dev); + struct udevice *cpu; + u32 reg; + ulong start; + int ret; + + /* Thermal throttle activation offset */ + ret = uclass_first_device_err(UCLASS_CPU, &cpu); + if (ret) + return log_msg_ret("Cannot find CPU", ret); + cpu_configure_thermal_target(cpu); + + /* + * Software Core Disable Mask (P_CR_CORE_DISABLE_MASK_0_0_0_MCHBAR). + * Enable all cores here. + */ + writel(0, MCHBAR_REG(CORE_DISABLE_MASK)); + + /* P-Unit bring up */ + reg = readl(MCHBAR_REG(BIOS_RESET_CPL)); + if (reg == 0xffffffff) { + /* P-unit not found */ + debug("Punit MMIO not available\n"); + return -ENOENT; + } + + /* Set Punit interrupt pin IPIN offset 3D */ + pci_x86_write_config(plat->bdf, PCI_INTERRUPT_PIN, 0x2, PCI_SIZE_8); + + /* Set PUINT IRQ to 24 and INTPIN LOCK */ + writel(PUINT_THERMAL_DEVICE_IRQ_VEC_NUMBER | + PUINT_THERMAL_DEVICE_IRQ_LOCK, + MCHBAR_REG(PUNIT_THERMAL_DEVICE_IRQ)); + + if (!IS_ENABLED(CONFIG_SOC_INTEL_GLK)) + clrsetbits_le32(MCHBAR_REG(0x7818), 0x1fe0, 0x220); + + /* Stage0 BIOS Reset Complete (RST_CPL) */ + enable_bios_reset_cpl(); + + /* + * Poll for bit 8 to check if PCODE has completed its action in response + * to BIOS Reset complete. We wait here till 1 ms for the bit to get + * set. + */ + start = get_timer(0); + while (!(readl(MCHBAR_REG(BIOS_RESET_CPL)) & PCODE_INIT_DONE)) { + if (get_timer(start) > 1) { + debug("PCODE Init Done timeout\n"); + return -ETIMEDOUT; + } + udelay(100); + } + debug("PUNIT init complete\n"); + + return 0; +} + +static int apl_punit_probe(struct udevice *dev) +{ + if (spl_phase() == PHASE_SPL) + return punit_init(dev); + + return 0; +} + +static int apl_punit_ofdata_to_platdata(struct udevice *dev) +{ + struct apl_punit_platdata *plat = dev_get_platdata(dev); + int root; + + root = pci_get_devfn(dev); + if (root < 0) + return log_msg_ret("Cannot get host-bridge PCI address", root); + plat->bdf = root; + + return 0; +} + +static const struct udevice_id apl_syscon_ids[] = { + { .compatible = "intel,apl-punit", .data = X86_SYSCON_PUNIT }, + { } +}; + +U_BOOT_DRIVER(syscon_intel_punit) = { + .name = "intel_punit_syscon", + .id = UCLASS_SYSCON, + .of_match = apl_syscon_ids, + .ofdata_to_platdata = apl_punit_ofdata_to_platdata, + .probe = apl_punit_probe, +};