From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists1p.gnu.org (lists1p.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A4AB6CD98E1 for ; Tue, 16 Jun 2026 19:02:46 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists1p.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1wZZ3N-0001KV-B6; Tue, 16 Jun 2026 15:02:31 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1wZZ39-0001Hn-BI for qemu-riscv@nongnu.org; Tue, 16 Jun 2026 15:02:16 -0400 Received: from mail-pf1-x42d.google.com ([2607:f8b0:4864:20::42d]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1wZZ36-0007UT-Br for qemu-riscv@nongnu.org; Tue, 16 Jun 2026 15:02:14 -0400 Received: by mail-pf1-x42d.google.com with SMTP id d2e1a72fcca58-84237c55ef9so3176432b3a.0 for ; Tue, 16 Jun 2026 12:02:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1781636531; x=1782241331; darn=nongnu.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=JTCwpCF51RY4lRUcaJPa9zU/4fcfYbZj1EPKJSo44zo=; b=l4Q3ZnDxm8bMUGEUgs2CW1MxfI/0xFbwhs73c+TiD6sWAOStFyKuZku1Oy8dfzlT+t 04h8jNgFtnvdD75ucXkcydV/MDm/l3LK5NP900YXoxTj1ksKFXQzwxWH6OwTME5WLZCf 4T7yYN7CXj6EUzIgU/6c9ErBvNdTSuTFQuKsYKc/dYFNL55D9Lg+2PbTLBcGgDwee3m9 fKaLB7hLwAF6uNS7qJig45sNjkqZYNnjv8mnJoeMCcn0V7qErAffijBSD5xyNQDiTD9/ QCYcbEw5w2vZi8Agp5+Hk7dNl17Cu80wn9zoTbWI5I5nR9zkeaydkceCK75Iu+rIWlNC Rhlw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1781636531; x=1782241331; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=JTCwpCF51RY4lRUcaJPa9zU/4fcfYbZj1EPKJSo44zo=; b=g+HmNmI8BGo9Of2Ln/E/H5OmT/8b+JNU8LYiLFi5IJePQsAeiVTyfDtmgqG4xF28dQ TU7Jnh3f5zTRs9PxWf8aREYPewjQ8a7/K8fJvHjbQcfw+ok6C+OhZ5hY7JudKBKqpocH jpOJRaBdu1M3pwtIdSbSjInyMMT1VyKrxh1CMc3NlE2XUwPPcs590/Q+hurla/GHReFv 8UE4NjkLcYxC5m6OWLTTtgN+Lq3j/XiaB8hmdha7V+bJnawteUZp9GdB8OP8PIBORT4+ mGmuv4NtXXGTB/j+JOyeelEm9RWAGhCDBXdbEAZLiBUKyU1C+R8U26JvbeZvIB8j2Dzi 67zg== X-Forwarded-Encrypted: i=1; AFNElJ965zjVDwpqd63Eh+XZ+CkB0bK5RA8sa3tA5VRoEokAFPFM4V2h0RnlmDw+QKKL6PzVLg/YTvV0ntKa@nongnu.org X-Gm-Message-State: AOJu0YxkT7SU62DpOMbO+ueqAlrvnJHNSi9qK8tK4OFdLZv88426NeVK IsUaEN/EjnJ4oRlhxIXnRo8l1+x7S4w/QxeWX+KKdKUghsStoGVgGA8a X-Gm-Gg: Acq92OFrfd4XabdD+Fykp30A6n98exUQiY1j5jfkSpgYCDCJxyCF76fwzD+4cMBgChV j/QqZg6kEm3a7dhynxu11X3KGQD2z1xZCefzDLssvdgp/0F9fL5EZzGEExGtsJBkYBVHPmaBKm9 QO4Gu073LK/TKG8i83dvzCb/YCgs9KW3LtLaTzHCczDCglN+brxeAIjkpBhLp75ntbSw++pBvR0 bDh0jCoFIG4G/iiAC+PkjaEmOM4LRRrdaggquc+Jy6frhzswWxJnxt30sCzi5rRbU6IxUzWxFoq vsoAqpVJ/MrCxAwk4YvkpuCY/vxzBzCOcgVfCIXT69If2Ui9l57877XfzJFA0sUuJpJC8vKb1Di 15r9aTIjeCP0FMKiSeuu884Iab0zSp7O9dca8cVUy1JPg3W2URWxK4zkhG0wlxlG7o8shzuNCst It0exsbqaEu5b4xhBgKIS7QmJ33PxE4dsWOndxGtycOYp5z9f4M8odbse/bKvnJamy9UddOuAEg s//Jhn3/Z4gu2E7npRBb+VOMNmA2kE35w== X-Received: by 2002:a05:6a00:a20b:b0:842:4982:82a with SMTP id d2e1a72fcca58-845247b90a2mr327776b3a.45.1781636530669; Tue, 16 Jun 2026 12:02:10 -0700 (PDT) Received: from visitorckw-work01.c.googlers.com.com (32.237.80.34.bc.googleusercontent.com. [34.80.237.32]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-8434ac9c474sm12671540b3a.2.2026.06.16.12.02.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 16 Jun 2026 12:02:10 -0700 (PDT) From: Kuan-Wei Chiu To: pbonzini@redhat.com, marcandre.lureau@redhat.com, alistair.francis@wdc.com, farosas@suse.de, lvivier@redhat.com Cc: liwei1518@gmail.com, daniel.barboza@oss.qualcomm.com, zhiwei_liu@linux.alibaba.com, chao.liu.zevorn@gmail.com, jserv@ccns.ncku.edu.tw, eleanor15x@gmail.com, marscheng@google.com, qemu-devel@nongnu.org, qemu-riscv@nongnu.org, Kuan-Wei Chiu Subject: [PATCH v3 1/5] hw/char: Add dw8250 UART Date: Tue, 16 Jun 2026 19:01:43 +0000 Message-ID: <20260616190147.1286316-2-visitorckw@gmail.com> X-Mailer: git-send-email 2.54.0.1136.gdb2ca164c4-goog In-Reply-To: <20260616190147.1286316-1-visitorckw@gmail.com> References: <20260616190147.1286316-1-visitorckw@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=2607:f8b0:4864:20::42d; envelope-from=visitorckw@gmail.com; helo=mail-pf1-x42d.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-riscv@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-riscv-bounces+qemu-riscv=archiver.kernel.org@nongnu.org Sender: qemu-riscv-bounces+qemu-riscv=archiver.kernel.org@nongnu.org Add the dw8250 uart support. This hardware is a widely used 16550A derivative that includes additional registers. Without this specific device support, the Linux 8250_dw driver fails to probe the extended registers (UCV, CPR, etc.), which are essential for correct feature detection: [ 0.293566] Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled [ 0.306929] Oops - store (or AMO) access fault [#1] [ 0.307020] Modules linked in: [ 0.307192] CPU: 0 UID: 0 PID: 1 Comm: swapper/0 Not tainted 7.0.0 #1 PREEMPTLAZY [ 0.307250] Hardware name: Milk-V Duo (DT) [ 0.307294] epc : dw8250_setup_port+0x22/0x520 [ 0.307504] ra : dw8250_probe+0x57e/0x5b8 [ 0.307518] epc : ffffffff80708dd6 ra : ffffffff8070a49e sp : ffffffc60000b820 [ 0.307525] gp : ffffffff81a32ba8 tp : ffffffd602180cc0 t0 : 0000000000000073 [ 0.307533] t1 : 000000000000006c t2 : 0000000000000000 s0 : ffffffc60000b830 [ 0.307539] s1 : ffffffd6028c8640 a0 : ffffffc60000b848 a1 : ffffffff813162c1 [ 0.307546] a2 : ffffffff813162c0 a3 : ffffffd6028c8640 a4 : ffffffc60002d0b4 [ 0.307552] a5 : 0000000000000001 a6 : 0000000000000094 a7 : 0000000000000060 [ 0.307558] s2 : ffffffd60225d410 s3 : ffffffd60225d400 s4 : 0000000000000000 [ 0.307573] s5 : ffffffff80e31a48 s6 : 0000000000000008 s7 : 0000000000000000 [ 0.307584] s8 : 0000000000000149 s9 : 0000000000000000 s10: 0000000000000000 [ 0.307590] s11: 0000000000000000 t3 : ffffffd602007c00 t4 : ffffffff81601540 [ 0.307604] t5 : 0000000000000003 t6 : ffffffd602a42f82 ssp : 0000000000000000 [ 0.307611] status: 0000000200000120 badaddr: ffffffc60002d0b4 cause: 0000000000000007 [ 0.307652] [] dw8250_setup_port+0x22/0x520 [ 0.307695] [] dw8250_probe+0x57e/0x5b8 [ 0.307702] [] platform_probe+0x46/0x80 [ 0.307708] [] really_probe+0x84/0x22c [ 0.307715] [] __driver_probe_device+0x5c/0xd4 [ 0.307721] [] driver_probe_device+0x2e/0xf4 [ 0.307727] [] __driver_attach+0x6e/0x14c [ 0.307734] [] bus_for_each_dev+0x60/0xb0 [ 0.307740] [] driver_attach+0x1a/0x24 [ 0.307746] [] bus_add_driver+0xca/0x1d8 [ 0.307752] [] driver_register+0x3e/0xdc [ 0.307757] [] __platform_driver_register+0x1c/0x24 [ 0.307779] [] dw8250_platform_driver_init+0x1a/0x24 [ 0.307793] [] do_one_initcall+0x4e/0x2a4 [ 0.307800] [] kernel_init_freeable+0x226/0x2b0 [ 0.307807] [] kernel_init+0x1c/0x144 [ 0.307813] [] ret_from_fork_kernel+0x18/0x164 [ 0.307820] [] ret_from_fork_kernel_asm+0x16/0x18 [ 0.307914] Code: 3683 2085 0b63 32f7 000f 0140 6918 4785 0713 0b47 (c31c) 2583 [ 0.308041] ---[ end trace 0000000000000000 ]--- [ 0.308180] Kernel panic - not syncing: Fatal exception in interrupt [ 0.315760] ---[ end Kernel panic - not syncing: Fatal exception in interrupt ]--- Signed-off-by: Kuan-Wei Chiu Reviewed-by: Chao Liu --- hw/char/Kconfig | 4 ++ hw/char/dw8250.c | 118 +++++++++++++++++++++++++++++++++++++++ hw/char/meson.build | 1 + include/hw/char/dw8250.h | 27 +++++++++ 4 files changed, 150 insertions(+) create mode 100644 hw/char/dw8250.c create mode 100644 include/hw/char/dw8250.h diff --git a/hw/char/Kconfig b/hw/char/Kconfig index 020c0a84bb..418d99b757 100644 --- a/hw/char/Kconfig +++ b/hw/char/Kconfig @@ -95,3 +95,7 @@ config IP_OCTAL_232 bool default y depends on IPACK + +config DW8250 + bool + select SERIAL diff --git a/hw/char/dw8250.c b/hw/char/dw8250.c new file mode 100644 index 0000000000..4ec829ceaf --- /dev/null +++ b/hw/char/dw8250.c @@ -0,0 +1,118 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Synopsys DesignWare APB UART (DW 8250) + * + * Copyright (c) 2026 Kuan-Wei Chiu + */ + +#include "qemu/osdep.h" +#include "qapi/error.h" +#include "hw/char/dw8250.h" +#include "hw/core/qdev-properties.h" +#include "hw/core/qdev-properties-system.h" + +#define DW_UART_REGION_SIZE 0x100 + +#define DW_UART_RE_EN 0xB4 /* Receiver Output Enable Register */ +#define DW_UART_DLF 0xC0 /* Divisor Latch Fraction Register */ +#define DW_UART_CPR 0xF4 /* Component Parameter Register */ +#define DW_UART_UCV 0xF8 /* UART Component Version */ +#define DW_UART_CTR 0xFC /* Component Type Register */ + +#define DW_UART_UCV_VALUE 0x3332332A /* "323*" -> v3.23a */ +#define DW_UART_CTR_VALUE 0x44570110 /* "DW" */ + +static uint64_t dw8250_ext_read(void *opaque, hwaddr addr, unsigned int size) +{ + switch (addr) { + case DW_UART_UCV: + return DW_UART_UCV_VALUE; + case DW_UART_CPR: + return 0x00000000; /* No advanced features (DMA, extra FIFOs) */ + case DW_UART_CTR: + return DW_UART_CTR_VALUE; + + case DW_UART_RE_EN: + case DW_UART_DLF: + /* + * Return 0 to indicate these optional features + * (RS485 and Fractional Divisor) are not implemented. + */ + return 0x00000000; + + default: + return 0; + } +} + +static void dw8250_ext_write(void *opaque, hwaddr addr, uint64_t val, unsigned int size) +{ +} + +static const MemoryRegionOps dw8250_ext_ops = { + .read = dw8250_ext_read, + .write = dw8250_ext_write, + .endianness = DEVICE_LITTLE_ENDIAN, + .valid.min_access_size = 4, + .valid.max_access_size = 4, +}; + +static void dw8250_instance_init(Object *obj) +{ + DW8250State *s = DW8250(obj); + + s->serial_mm = qdev_new("serial-mm"); + object_property_add_child(obj, "serial-mm", OBJECT(s->serial_mm)); + object_property_add_alias(obj, "chardev", OBJECT(s->serial_mm), "chardev"); +} + +static void dw8250_realize(DeviceState *dev, Error **errp) +{ + DW8250State *s = DW8250(dev); + SysBusDevice *sbd = SYS_BUS_DEVICE(dev); + SysBusDevice *serial_sbd = SYS_BUS_DEVICE(s->serial_mm); + + memory_region_init(&s->container, OBJECT(dev), "dw8250-container", + DW_UART_REGION_SIZE); + sysbus_init_mmio(sbd, &s->container); + + qdev_prop_set_uint8(s->serial_mm, "regshift", s->regshift); + qdev_prop_set_uint8(s->serial_mm, "endianness", DEVICE_LITTLE_ENDIAN); + sysbus_realize(serial_sbd, errp); + + memory_region_init_io(&s->ext_iomem, OBJECT(dev), &dw8250_ext_ops, s, + "dw8250-ext", DW_UART_REGION_SIZE); + memory_region_add_subregion(&s->container, 0, &s->ext_iomem); + + memory_region_add_subregion_overlap(&s->container, 0, + sysbus_mmio_get_region(serial_sbd, 0), 1); + + sysbus_pass_irq(sbd, serial_sbd); +} + +static const Property dw8250_properties[] = { + DEFINE_PROP_UINT8("regshift", DW8250State, regshift, 2), +}; + +static void dw8250_class_init(ObjectClass *klass, const void *data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + + dc->realize = dw8250_realize; + device_class_set_props(dc, dw8250_properties); +} + +static const TypeInfo dw8250_info = { + .name = TYPE_DW8250, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_size = sizeof(DW8250State), + .instance_init = dw8250_instance_init, + .class_init = dw8250_class_init, +}; + +static void dw8250_register_types(void) +{ + type_register_static(&dw8250_info); +} + +type_init(dw8250_register_types) diff --git a/hw/char/meson.build b/hw/char/meson.build index fc3d7ee506..b2250ee6ae 100644 --- a/hw/char/meson.build +++ b/hw/char/meson.build @@ -38,6 +38,7 @@ system_ss.add(when: 'CONFIG_STM32L4X5_USART', if_true: files('stm32l4x5_usart.c' system_ss.add(when: 'CONFIG_MCHP_PFSOC_MMUART', if_true: files('mchp_pfsoc_mmuart.c')) system_ss.add(when: 'CONFIG_HTIF', if_true: files('riscv_htif.c')) system_ss.add(when: 'CONFIG_GOLDFISH_TTY', if_true: files('goldfish_tty.c')) +system_ss.add(when: 'CONFIG_DW8250', if_true: files('dw8250.c')) specific_ss.add(when: 'CONFIG_TERMINAL3270', if_true: files('terminal3270.c')) specific_ss.add(when: 'CONFIG_PSERIES', if_true: files('spapr_vty.c')) diff --git a/include/hw/char/dw8250.h b/include/hw/char/dw8250.h new file mode 100644 index 0000000000..59396ad202 --- /dev/null +++ b/include/hw/char/dw8250.h @@ -0,0 +1,27 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Synopsys DesignWare APB UART (DW 8250) + * + * Copyright (c) 2026 Kuan-Wei Chiu + */ + +#ifndef HW_CHAR_DW8250_H +#define HW_CHAR_DW8250_H + +#include "hw/core/sysbus.h" +#include "qom/object.h" + +#define TYPE_DW8250 "dw8250" +OBJECT_DECLARE_SIMPLE_TYPE(DW8250State, DW8250) + +struct DW8250State { + SysBusDevice parent_obj; + + MemoryRegion container; + MemoryRegion ext_iomem; + DeviceState *serial_mm; + + uint8_t regshift; +}; + +#endif -- 2.54.0.1136.gdb2ca164c4-goog