From patchwork Tue Apr 7 07:25:17 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Joel Stanley X-Patchwork-Id: 1267280 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=jms.id.au Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20161025 header.b=W/3Bn1gT; dkim-atps=neutral Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 48xJrd5y51z9sSc for ; Tue, 7 Apr 2020 17:27:12 +1000 (AEST) Received: from localhost ([::1]:42522 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jLidY-0005Yn-SU for incoming@patchwork.ozlabs.org; Tue, 07 Apr 2020 03:27:09 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:41811) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jLic3-0005Of-5u for qemu-devel@nongnu.org; Tue, 07 Apr 2020 03:25:36 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1jLic1-0003JC-Tq for qemu-devel@nongnu.org; Tue, 07 Apr 2020 03:25:35 -0400 Received: from mail-pg1-x543.google.com ([2607:f8b0:4864:20::543]:38695) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1jLibz-0003AB-9o; Tue, 07 Apr 2020 03:25:31 -0400 Received: by mail-pg1-x543.google.com with SMTP id m17so1298316pgj.5; Tue, 07 Apr 2020 00:25:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=xSQjae3iHp8vDRdLTBEjdVkFcRaIif/B6y8hlJTqhks=; b=W/3Bn1gTxVlm6EolmJPogDFtbHGj29NTffMytH1J0dkzzc4idq8uDlZJ6uFVPthMp1 hoyjaXfksqCE+ixUmxa+/ZAHy9xkuib1qq5ZVMOuPmNuc90MjSO2J03MppN32auN4/zs +pjC+u6GuH74KtYqfwdvN+70vb1BUMS7yxxB18OLNLl+RKKjaINt0qm/gu4dv3fSb3m1 P3ZTBxAQA5cLrb3KOfhgob6vZyXWnKKCszI9d1HRka57jaav6jUz31R1GotnBRHm6VQs LMnju+j83C9M8BxNs9pp/WtodNXtu17RXBSAqIZ0CrgZJosq8233/Hrz4/JY0fKAWdcv M0Lg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id :mime-version:content-transfer-encoding; bh=xSQjae3iHp8vDRdLTBEjdVkFcRaIif/B6y8hlJTqhks=; b=SF080vFbGbc4F/zcPhnjJkRsoKsO2zUt/HoNlYFAV8/9eYGyjuXYsFgor0HbqW4U8Q vbubaM2AMx5bSb3WynkSh6e6aL7tvKpxUoBqey6sS02D/w54TSpVCkfTDff4W7wIwjjh D75vn/+yDAMex73lBhD4pOZ6RAabQO9roUiNom0RMAbSGI42M5SnpFFsInMzHkOPwzuT 41G3ttq+dmVc5kuYCXcR2aZuHXxpv/eZ9znj85gnJ9qvqCXZypEV8lTM7UhkRKrOUGlT ZJGIlmp4FJ3A4p4PXBIPYEnByjziV6IO406ck5ywmCEPE+lpM9msTXABohR0VLC2g86S YxbA== X-Gm-Message-State: AGi0PuaNc9WIopxbGTJ3sIpdnzh2WTEzzgNj4azPmdrbmmb9D4bD+OaV oNKX6nhbfidcFMOySlSBhyA= X-Google-Smtp-Source: APiQypLcqngxCy/MFC9HQ1YJSoo/tnNdxSWzl2MskWSFurd6AZsJvJm2HxRasJgc0AbCpauqp+qcyw== X-Received: by 2002:a62:e515:: with SMTP id n21mr1291117pff.103.1586244329822; Tue, 07 Apr 2020 00:25:29 -0700 (PDT) Received: from localhost.localdomain ([45.124.203.18]) by smtp.gmail.com with ESMTPSA id 189sm13177249pfg.170.2020.04.07.00.25.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 07 Apr 2020 00:25:29 -0700 (PDT) From: Joel Stanley To: =?utf-8?q?C=C3=A9dric_Le_Goater?= , Peter Maydell Subject: [PATCH] aspeed: Add boot stub for smp booting Date: Tue, 7 Apr 2020 16:55:17 +0930 Message-Id: <20200407072517.671521-1-joel@jms.id.au> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2607:f8b0:4864:20::543 X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Andrew Jeffery , qemu-arm@nongnu.org, qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" This is a boot stub that is similar to the code u-boot runs, allowing the kernel to boot the secondary CPU. u-boot works as follows: 1. Initialises the SMP mailbox area in the SCU at 0x1e6e2180 with default values 2. Copies a stub named 'mailbox_insn' from flash to the SCU, just above the mailbox area 3. Sets AST_SMP_MBOX_FIELD_READY to a magic value to indicate the secondary can begin execution from the stub 4. The stub waits until the AST_SMP_MBOX_FIELD_GOSIGN register is set to a magic value 5. Jumps to the address in AST_SMP_MBOX_FIELD_ENTRY, starting Linux Linux indicates it is ready by writing the address of its entrypoint function to AST_SMP_MBOX_FIELD_ENTRY and the 'go' magic number to AST_SMP_MBOX_FIELD_GOSIGN. The secondary CPU sees this at step 4 and breaks out of it's loop. To be compatible, a fixed qemu stub is loaded into the mailbox area. As qemu can ensure the stub is loaded before execution starts, we do not need to emulate the AST_SMP_MBOX_FIELD_READY behaviour of u-boot. The secondary CPU's program counter points to the beginning of the stub, allowing qemu to start secondaries at step four. Reboot behaviour is preserved by resetting AST_SMP_MBOX_FIELD_GOSIGN when the secondaries are reset. This is only configured when the system is booted with -kernel and qemu does not execute u-boot first. Signed-off-by: Joel Stanley Reviewed-by: Cédric Le Goater Tested-by: Cédric Le Goater --- hw/arm/aspeed.c | 65 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 65 insertions(+) diff --git a/hw/arm/aspeed.c b/hw/arm/aspeed.c index a6a2102a93cb..bc4386cc6174 100644 --- a/hw/arm/aspeed.c +++ b/hw/arm/aspeed.c @@ -116,6 +116,58 @@ static const MemoryRegionOps max_ram_ops = { .endianness = DEVICE_NATIVE_ENDIAN, }; +#define AST_SMP_MAILBOX_BASE 0x1e6e2180 +#define AST_SMP_MBOX_FIELD_ENTRY (AST_SMP_MAILBOX_BASE + 0x0) +#define AST_SMP_MBOX_FIELD_GOSIGN (AST_SMP_MAILBOX_BASE + 0x4) +#define AST_SMP_MBOX_FIELD_READY (AST_SMP_MAILBOX_BASE + 0x8) +#define AST_SMP_MBOX_FIELD_POLLINSN (AST_SMP_MAILBOX_BASE + 0xc) +#define AST_SMP_MBOX_CODE (AST_SMP_MAILBOX_BASE + 0x10) +#define AST_SMP_MBOX_GOSIGN 0xabbaab00 + +static void aspeed_write_smpboot(ARMCPU *cpu, + const struct arm_boot_info *info) +{ + static const uint32_t poll_mailbox_ready[] = { + /* + * r2 = per-cpu go sign value + * r1 = AST_SMP_MBOX_FIELD_ENTRY + * r0 = AST_SMP_MBOX_FIELD_GOSIGN + */ + 0xee100fb0, /* mrc p15, 0, r0, c0, c0, 5 */ + 0xe21000ff, /* ands r0, r0, #255 */ + 0xe59f201c, /* ldr r2, [pc, #28] */ + 0xe1822000, /* orr r2, r2, r0 */ + + 0xe59f1018, /* ldr r1, [pc, #24] */ + 0xe59f0018, /* ldr r0, [pc, #24] */ + + 0xe320f002, /* wfe */ + 0xe5904000, /* ldr r4, [r0] */ + 0xe1520004, /* cmp r2, r4 */ + 0x1afffffb, /* bne */ + 0xe591f000, /* ldr pc, [r1] */ + AST_SMP_MBOX_GOSIGN, + AST_SMP_MBOX_FIELD_ENTRY, + AST_SMP_MBOX_FIELD_GOSIGN, + }; + + rom_add_blob_fixed("aspeed.smpboot", poll_mailbox_ready, + sizeof(poll_mailbox_ready), + info->smp_loader_start); +} + +static void aspeed_reset_secondary(ARMCPU *cpu, + const struct arm_boot_info *info) +{ + AddressSpace *as = arm_boot_address_space(cpu, info); + CPUState *cs = CPU(cpu); + + /* info->smp_bootreg_addr */ + address_space_stl_notdirty(as, AST_SMP_MBOX_FIELD_GOSIGN, 0, + MEMTXATTRS_UNSPECIFIED, NULL); + cpu_set_pc(cs, info->smp_loader_start); +} + #define FIRMWARE_ADDR 0x0 static void write_boot_rom(DriveInfo *dinfo, hwaddr addr, size_t rom_size, @@ -270,6 +322,19 @@ static void aspeed_machine_init(MachineState *machine) } } + if (machine->kernel_filename) { + /* With no u-boot we must set up a boot stub for the secondary CPU */ + MemoryRegion *smpboot = g_new(MemoryRegion, 1); + memory_region_init_ram(smpboot, OBJECT(bmc), "aspeed.smpboot", + 0x80, &error_abort); + memory_region_add_subregion(get_system_memory(), + AST_SMP_MAILBOX_BASE, smpboot); + + aspeed_board_binfo.write_secondary_boot = aspeed_write_smpboot; + aspeed_board_binfo.secondary_cpu_reset_hook = aspeed_reset_secondary; + aspeed_board_binfo.smp_loader_start = AST_SMP_MBOX_CODE; + } + aspeed_board_binfo.ram_size = ram_size; aspeed_board_binfo.loader_start = sc->memmap[ASPEED_SDRAM]; aspeed_board_binfo.nb_cpus = bmc->soc.num_cpus;