苹果对外招聘RISC-V工程师，或欲节省每年数百万美元的ARM专利费

{"type":"doc","content":[{"type":"blockquote","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"苹果正在向更加自主可控的芯片研发道路迈进。"}]}]},{"type":"heading","attrs":{"align":null,"level":2},"content":[{"type":"text","text":"苹果招聘 RISC-V 工程师"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"近日，苹果发布"},{"type":"link","attrs":{"href":"https:\/\/jobs.apple.com\/en-us\/details\/200282667\/risc-v-high-performance-programmer","title":"xxx","type":null},"content":[{"type":"text","text":"招聘启事"}]},{"type":"text","text":"称正在为其核心操作系统团队的 Vector and Numerics Group (VaNG) 小组寻找对 RISC-V 指令集架构 (ISA) 和 ARM 的 Neon vector ISA 有详细了解且有丰富经验的开发者。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"image","attrs":{"src":"https:\/\/static001.geekbang.org\/wechat\/images\/5b\/5b15135010e73c0e0f724054e7d3c7e3.jpeg","alt":null,"title":null,"style":null,"href":null,"fromPaste":false,"pastePass":false}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"RISC-V 是一种开源指令集架构（ISA），允许设备制造商在不支付许可证或版税的情况下设计、制造和销售 RISC-V 芯片和软件。RISC-V 比 ARM 更晚出现，但 RISC-V 的架构设计比 ARM 更为精简，同时 RISC-V 还有模块化的特点，非常适合物联网等等新的应用，目前 RISC-V 很多的创新都是通过用户在现有的指令架构上面增加指令子集的方式来实现的。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"ARM 的芯片设计则是基于早期 RISC 架构。ARM 将这种设计授权给多家芯片厂商，而此类芯片几乎被用于所有智能手机。在桌面和服务器市场，既有芯片架构的地位非常牢固。正因如此，媒体猜测苹果此举旨在节省每年数百万美元的专利费用，毕竟苹果使用 ARM 内核的设备越来越多，其需要支付的费用也越来越多。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"根据招聘广告，这名工程师将在苹果产品上采用“创新的 RISC-V 解决方案和最先进的程序”。具体地说，苹果希望未来的工程师能够使用 RISC-V 指令集，并了解 ARM。该招聘仅可表明苹果正在探索 RISC-V 的使用，但最终是否决定采用这项开源技术以及是否会用其替代现有芯片架构都是未知的。"}]},{"type":"heading","attrs":{"align":null,"level":2},"content":[{"type":"text","text":"苹果在芯片设计上逐步摆脱外部依赖"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"过去一年，苹果放弃英特尔转而投向自研芯片的事情引起了业界的广泛关注。"},{"type":"link","attrs":{"href":"https:\/\/www.infoq.cn\/article\/ULKfa6cJ1uVzME9JQhJm","title":"xxx","type":null},"content":[{"type":"text","text":"M1 "}]},{"type":"text","text":"是苹果首款自研芯片，于 2020 年年底正式对外发布，并首次加持在 Mac 上。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"虽然早在 2020 年 6 月的 WWDC 大会上，苹果就已经宣布将发布采用自研芯片的新一代 Macbook 系列产品，但彼时并没有透露过多的细节。直到 2020 年 11 月 11 日，随着一系列新产品的亮相，苹果 M1 芯片的详细参数和性能表现也走到台前。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"苹果方面表示，M1 芯片搭载了许多世界顶级工艺的产品，包括世界上最快的 CPU 内核、最快的 IGPU。“苹果花了十几年的时间来创造和优化 Apple 芯片，因为芯片是 iPhone、iPad 和 Apple Watch 的核心。现在我们希望将其引入 Mac，因此 Mac 可以凭借令人难以置信的性能、自定义技术和行业领先的芯片来实现巨大的飞跃。”"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"苹果公司认为，M1 是迄今为止性能最高的芯片，并且低功耗高效内核可提供与当前基于英特尔的双核 MacBook Air 相似的性能。当然，高性能内核要快得多。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"遵循长期以来生产 ARM 芯片的标准，CPU 由四个大内核和四个小内核组成。大内核共享 12MB 的 L2 缓存，小内核共享 4MB 的 L2。两种内核共同工作时，当限于 10W TDP 时，它们的速度是“最新 PC 笔记本电脑芯片”的两倍，并且如果散热足够好，它们的运行速度甚至会更快。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"在 GPU 方面，M1 将具有多达八个内核和 128 个执行单元。它能够处理多达 24576 个并发线程，且峰值性能为 2.6 teraflops。苹果公司认为，这将使 Mac 拥有全世界笔记本电脑中最快的集成图形体验。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"值得注意的是，M1 的 16 核神经网络引擎，每秒可以完成 11 万亿次运算，机器学习性能大幅提升。机器上还有先进的媒体编码 \/ 解码引擎以及图像信号处理器。苹果的 Secure Enclave 也嵌入到芯片组中，不需要单独的 T2 芯片。与大多数非英特尔平台不同的是，新的芯片组支持 Thunderbolt，因此苹果用户将能够继续使用快速的外部存储和其他配件。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"半年之内，M1 芯片已用在 MacBook、iMac、iPad Pro 多款产品上。随着 M1 芯片成为苹果产品线的标配，苹果生态内硬件性能得到进一步提升，软件生态维度也得以扩充，逐步摆脱了对英特尔的依赖。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"如今看来，苹果可能已经在筹划更彻底的摆脱外部限制，进一步降低成本，从开源的 RISC-V 架构下手。两者相较，ARM 是一个完全私有化、封闭式的指令机器；而 RISC-V 更像是 Linux ，由完全中立的国际组织拥有，是一个完全开放的架构。这样的特点让 RISC-V 受到了众多开发者和企业的关注。"}]},{"type":"heading","attrs":{"align":null,"level":2},"content":[{"type":"text","text":"RISC-V 值得押注吗？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"最近几年，业界也常常有人把 "},{"type":"link","attrs":{"href":"https:\/\/www.infoq.cn\/article\/oelkCJXG5zO*wOgZJjtP","title":"xxx","type":null},"content":[{"type":"text","text":"RISC-V"}]},{"type":"text","text":" 称作“中国半导体行业最后一次赶超欧美的希望”。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"目前的国际 CPU 市场，由两个指令集架构“独裁者”占据：以英特尔为主的 x86 架构和 ARM 推行的 ARM 架构。尽管也曾有过类似 MIPS、PowerPC 等指令集架构的一时风光，但其规模仍难及两个多年经营的庞然大物。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"2010 年，开源指令集架构 RISC-V 首次出现在美国加州大学伯克利分校，其开源架构的形式很快就吸引了包括 IBM、恩智浦、WeaternDigital、NVIDIA、Qualcomm、三星、Google、华为、Tesla 等各大厂商的加盟。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"面对 RISC-V 的迅猛发展，同样基于精简指令集（RISC）原则的 ARM 架构受到了不小的影响，面对 RISC-V 巨大的潜力，ARM 公司就曾建立专门网站，从“成本、生态系统、碎片化风险、安全性、设计保证”五个方面攻击 RISC-V 。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"时至今日，该网站早已以失败告终，而 RISC-V 在广大业界志愿者的支持下，仍然焕发着蓬勃生机，且 RISC-V 被认为更加“自主可控”。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"RISC-V 的优势，在于其包含了 CPU 发展过程中优秀的创新点，在技术上非常完备。因为“年轻”，它不仅非常精简，而且没有所谓的“历史包袱”。比如，一个技术手册，由于 ARM 和英特尔都需要与自己的上一代产品兼容，可能需要 2000 多页，而 RISC-V 却只需要几百页。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"RISC-V 架构具有简单和灵活的特性，非常适合部署到物联网、控制器、数据中心的专用芯片和边缘计算等应用场景。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"但对于移动端和 PC 端市场而言，RISC-V 的生态远未成熟到与英特尔、ARM 等“技术大鳄”相匹敌的地步。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"此外，RISC-V 强调完全开源的设计，并且让取用者可任意加上专属指令集，甚至可以自由选择将架构封闭还是维持开源。这样就导致了 RISC-V 架构与过去的 MIPS 架构出现了同样问题：虽然拥有更多的指令集，却无法共用。当各个公司做出具有本身公司特色的芯片时，如果他们选择将自己的专属指令集保密，那么若干年后，很可能出现芯片互不兼容的情况，而这样的碎片化问题往往是不利于产业发展的。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"不过，随着越来越多的厂商和开发者加入 RISC-V 的阵营，其生态逐渐丰富，已经占据开源指令集架构的主流，是目前很多渴望研发“自主可控”芯片厂商很好的选择，相信未来会出现很好的示例。"}]}]}