Linux 5.18内核在Arm、RISC-V和MIPS的主要更新一览

Linux 5.18版本内核的一些亮点：

更快的编译时间——建议重新构建内核头，以显著加快构建速度；Linux 5.18在任务调度器中引入了其中一些更改。

Linux 5.18切换到C11–到目前为止，Linux内核一直依赖于C89标准（1989年发布）。由于LWN文章中解释的原因，新版本现在正在使用C11标准（2011）。

AMD Zen上更好的进程调度性能–AMD Zen CPU在每个节点上都有多个末级缓存（LLC），这使得一些工作负载难以优化运行。新代码允许调整multi LLC机器上的不平衡，直到节点之间的LLC应平衡为止。这已被证明可以显著提高某些工作负载的性能。

Btrfs更新—编码输入/输出、交叉装载重链接/重复数据消除和性能改进。Linux版本允许用户空间工具通过直接发送/接收读取和写入压缩数据块来避免额外的解压缩/压缩，增加了对交叉装载reflink/重复数据消除的支持，以及多项性能改进，尤其是对基于fsync的工作负载的支持。

Arm updates in Linux 5.18

Allwinner
- Allwinner H616 – Added RTC
- Allwinner R329 – Added ASoC driver
- PHY – Sun4i support for USB
- Added support for F1c100s
- Defconfig – Enable Allwinner F1C100
Rockchip
- Clock driver – Improve the clocks for the Rockchip rk3568 display outputs (parenting, pll-rates), Use of_device_get_match_data() instead of open-coding on Rockchip
  rk3568
- PHY driver – Rockchip naneng combo phy support for RK3568
- IOMMU driver – Use standard driver registration
- Add support for Reboot to Rockchip RK808
Amlogic
- Pinctrl – New driver for the Amlogic Meson S4 SoC
- ARM64 DT changes for Linux 5.18:
  - Initial support for Amlogic S4 (S802X2, S905Y4, S805X2G, S905W2)
  - Support for uart_ao_b & pwm_f on G12 SoCs
  - Remove CPU opps below 1GHz for SM1 (S905X3) boards because “Amlogic SM1 devices experience CPU stalls and random board wedges whenthe system idles and CPU cores clock down to lower opp points”
Samsung
- Pinctrl
  - Wakeup support on Samsung Exynos850 and ExynosAutov9
  - Fix OF reference leak in pinctrl driver probe error path.
    Correct list of handlers for Exynos850 ALIVE and CMGP pin banks.
  - Accept devicetrees with GPIO pin bank definitions named with a “-gpio-bank” suffix. This is necessary for later Samsung pinctrl bindings dtschema.
  - Convert Samsung pinctrl bindings to dtschema.
- Clock controller – Add support for Tesla FSD SoC clock controller within Samsung Exynos SoC clock controller drivers. The Tesla FSD’s clock controller is similar to Samsung Exynos one, so the entire driver structure can be re-used
- DTS ARM changes for Linux 5.18
  - Fix issues pointed out by DT schema checks: Add necessary clock controller inputs on Exynos5260, drop unsupported regulators on Odroid XU, add USB DWC3 supplies, drop old thermal properties from Exynos4210.
  - Add support for Samsung Chagall WiFi and a similar Samsung Klimt WiFi.
  - Add battery to Samsung P4Nnote.
- DTS ARM64 changes
  - Added Samsung Exynos 850 phone SoC and reference board
  - Added Samsung Exynos7885 with the Samsung Galaxy A8 (2018) phone
  - Tesla FSD (Fully Self-Driving), an automotive SoC loosely derived from the Samsung Exynos family.
  - Fix issues pointed out by DT schema checks: Add necessary clock controller inputs on Exynos7, add USB DWC3 supplies, drop old syscon phandle on Exynos5433.
  - Minor improvements and dtschema fixes (node names, properties).
Qualcomm
- Clock driver
  - Added Qualcomm SDX65 A7 PLL
  - Added Qualcomm SM6350 GPU clks
  - Added Qualcomm SM6125, SM6350, QCS2290 display clks
  - Added Qualcomm MSM8226 multimedia clks
  - Updated Qualcomm SC8280XP RPMCC
  - Added some missing clks on Qualcomm MSM8992/MSM8994/MSM8998 SoCs
  - Rework Qualcomm GCC bindings and convert SDM845 camera bindig to YAML
  - Convert various Qualcomm drivers to use clk_parent_data
  - Remove test clocks from various Qualcomm drivers
  - Crypto engine clks on Qualcomm IPQ806x + more freqs for SDCC/NSS
  - Qualcomm SM8150 EMAC, PCIe, UFS GDSCs
  - Better pixel clk frequency support on Qualcomm RCG2 clks
- PM – Fix issues with the Qualcomm’s cpufreq driver
- Pinctrl
  - New driver for Qualcomm SC8280XP SoC
  - Qualcomm SM8450 gets EGPIO support
- PCIe controller driver – Add SM8450 DT binding and driver support
- Net drivers
  - Qualcomm 802.11ax WiFi (ath11k)
    - Add LDPC FEC type and 802.11ax High-Efficiency data in radiotap
    - Enable RX PPDU stats in monitor co-exist mode
- irqchip
  - Simplify the Qualcomm PDC driver
  - Add support for the Qualcomm MPM wakeup gadget
- PHY
  - Qualcomm USB PHY support for sc8180x and sc8280xp, MSM8953
  - Qualcomm eDP PHY for sc7280
- Arm64 DT updates:
  - New platforms: Snapdragon 625 and Snapdragon 632 with initial description of Fairphone FP3 phone
  - IPQ6018 – USB reference period is corrected, GICv2m support is enabled and the max-link-speed for PCIe is specified.
  - IPQ8074 – Adds description of GIVv2m and SMEM, and ensures that TrustZone related memory is reserved from Linux.
  - Snapdragon 7c Gen 3 (SC7280) – Description of display, displayport, L3 interconnect, bluetooth, CPU opp-tables are added.
  - Snapdragon 845 – The OnePlus device gains fuel gauge and the platform gains GSI DMA support, which is enabled for SPI (for now).
  - Snapdragon 850 – The Lenovo Yoga C630 gains description of its backlight controls.
  - Fairphone 4 on the SM7225 platform gains proper WLED configuration.
  - Snapdragon 855 (SM8150) – Description of the limits hardware (LMh) is introduced and the SPI and I2C devices are wired to the GSI DMA controller.
  - Snapdragon 865 (SM8250) – The CPU and cluster idle states are introduced, the MSI interrupts for PCIe 1 and 2 are corrected and the CPUfreq driver gains knowledge about thermal pressure interrupts.
- Defconfig updates
  - The Qualcomm Snapdragon 8916 devices come in both 32- or 64-bit form, and even though the typical case so far has been to 64-bit, it’s possible to run the Dragonboard 410c in either mode.
  - Enable the relevant drivers in multi_v7_defconfig to enable this, and other Snapdragon 8916 devices to run the 32-bit kernel.
MediaTek
- MFD – Add support for MediaTek MT6366 PMIC to MT6358 IRQ
- Net drivers
  - Ethernet – Added MediaTek MT8195 switches
  - WiFi
    - Added MediaTek mt7916, MediaTek mt7921u USB adapters
    - background radar detection (mt76 driver)
    - Thermal management improvements on mt7915
    - SAR support for more mt76 platforms
    - MBSSID and 6 GHz band on mt7915

RISC-V changes

Allwinner D1 – Added support for I2S, MMC, SID, USB
SiFive
- A bunch of SiFive PLIC cleanups
- SiFive FU740 PCIe controller driver:
  - Drop redundant ‘-gpios’ from DT GPIO lookup
  - Force 2.5GT/s for initial device probe
StarFive
- Clock driver – Added Audio clks on StarFive JH7100 RISC-V SoC
Support for Sv57-based virtual memory.
Various improvements for the MicroChip PolarFire SOC and the associated Icicle dev board, should allow upstream kernels to boot without any additional modifications.
An improved memmove() implementation.
Support for the new Ssconfpmf and SBI PMU extensions, which allows for a much more useful perf implementation on RISC-V systems.
Support for restartable sequences.