On Wed, 2022-08-31 at 07:46 -0600, Simon Glass wrote: > Hi Weijie, > > On Wed, 31 Aug 2022 at 05:08, Weijie Gao <weijie....@mediatek.com> > wrote: > > > > Add basic CPU driver used to retrieve CPU model information. > > > > Signed-off-by: Weijie Gao <weijie....@mediatek.com> > > --- > > v2 changes: new > > --- > > drivers/cpu/Makefile | 1 + > > drivers/cpu/mtk_cpu.c | 106 > > ++++++++++++++++++++++++++++++++++++++++++ > > 2 files changed, 107 insertions(+) > > create mode 100644 drivers/cpu/mtk_cpu.c > > > > diff --git a/drivers/cpu/Makefile b/drivers/cpu/Makefile > > index 20884b1795..3b38ba9c58 100644 > > --- a/drivers/cpu/Makefile > > +++ b/drivers/cpu/Makefile > > @@ -9,6 +9,7 @@ obj-$(CONFIG_CPU) += cpu-uclass.o > > obj-$(CONFIG_ARCH_BMIPS) += bmips_cpu.o > > obj-$(CONFIG_ARCH_IMX8) += imx8_cpu.o > > obj-$(CONFIG_ARCH_AT91) += at91_cpu.o > > +obj-$(CONFIG_ARCH_MEDIATEK) += mtk_cpu.o > > obj-$(CONFIG_CPU_MPC83XX) += mpc83xx_cpu.o > > obj-$(CONFIG_CPU_RISCV) += riscv_cpu.o > > obj-$(CONFIG_CPU_MICROBLAZE) += microblaze_cpu.o > > diff --git a/drivers/cpu/mtk_cpu.c b/drivers/cpu/mtk_cpu.c > > new file mode 100644 > > index 0000000000..d00b4c669e > > --- /dev/null > > +++ b/drivers/cpu/mtk_cpu.c > > @@ -0,0 +1,106 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* > > + * Copyright (C) 2022 MediaTek Inc. All rights reserved. > > + * > > + * Author: Weijie Gao <weijie....@mediatek.com> > > + */ > > + > > +#include <linux/types.h> > > +#include <cpu.h> > > +#include <dm.h> > > +#include <fdt_support.h> > > +#include <mapmem.h> > > +#include <asm/global_data.h> > > +#include <linux/io.h> > > + > > +DECLARE_GLOBAL_DATA_PTR; > > dont't need this? > > > + > > +struct mtk_cpu_plat { > > + void __iomem *hwver_base; > > +}; > > + > > +static int mtk_cpu_get_desc(const struct udevice *dev, char *buf, > > int size) > > +{ > > + struct mtk_cpu_plat *plat = dev_get_plat(dev); > > + > > + snprintf(buf, size, "MediaTek MT%04X", readl(plat- > > >hwver_base)); > > + > > + return 0; > > +} > > + > > +static int mtk_cpu_get_count(const struct udevice *dev) > > +{ > > + return 1; > > +} > > + > > +static int mtk_cpu_get_vendor(const struct udevice *dev, char > > *buf, int size) > > +{ > > + snprintf(buf, size, "MediaTek"); > > + > > + return 0; > > +} > > + > > +static int mtk_cpu_probe(struct udevice *dev) > > +{ > > + struct mtk_cpu_plat *plat = dev_get_plat(dev); > > + const void *fdt = gd->fdt_blob, *reg; > > + int offset, parent, len, na, ns; > > + u64 addr; > > + > > + if (!fdt) > > + return -ENODEV; > > + > > + offset = fdt_path_offset(fdt, "/hwver"); > > This is very strange, but you should have a driver for that node, > e.g. > a SYSCON driver. Then from this driver you can obtain the address > with > syscon_get_first_range() or similar. > > > + if (offset < 0) > > + return -ENODEV; > > + > > + parent = fdt_parent_offset(fdt, offset); > > + if (parent < 0) > > + return -ENODEV; > > + > > + na = fdt_address_cells(fdt, parent); > > + if (na < 1) > > + return -ENODEV; > > + > > + ns = fdt_size_cells(gd->fdt_blob, parent); > > + if (ns < 0) > > + return -ENODEV; > > + > > + reg = fdt_getprop(gd->fdt_blob, offset, "reg", &len); > > + if (!reg) > > + return -ENODEV; > > + > > + if (ns) > > + addr = fdt_translate_address(fdt, offset, reg); > > + else > > + addr = fdt_read_number(reg, na); > > + > > All of the above should go away. We should use dev_read() / ofnode... > for device tree access.
OK. This is indeed tricky. I just didn't want to add reference to the hwver node for every cpu node. I'll change this using the regular way. > > > + plat->hwver_base = map_sysmem(addr, 0); > > + if (!plat->hwver_base) > > + return -EINVAL; > > + > > + return 0; > > +} > > + > > +static const struct cpu_ops mtk_cpu_ops = { > > + .get_desc = mtk_cpu_get_desc, > > + .get_count = mtk_cpu_get_count, > > + .get_vendor = mtk_cpu_get_vendor, > > +}; > > + > > +static const struct udevice_id mtk_cpu_ids[] = { > > + { .compatible = "arm,cortex-a7" }, > > + { .compatible = "arm,cortex-a53" }, > > + { .compatible = "arm,cortex-a73" }, > > + { /* sentinel */ } > > +}; > > + > > +U_BOOT_DRIVER(cpu_mtk) = { > > + .name = "mtk-cpu", > > + .id = UCLASS_CPU, > > + .of_match = mtk_cpu_ids, > > + .ops = &mtk_cpu_ops, > > + .probe = mtk_cpu_probe, > > + .plat_auto = sizeof(struct mtk_cpu_plat), > > + .flags = DM_FLAG_PRE_RELOC, > > +}; > > -- > > 2.17.1 > > > > Regards, > Simon