DWMSHC(4)

💅 DWMSHC(4) — the Kernel Interfaces Manual, but make it cute 🎀

okay so bestie, you're reading the dwmshc(4) page and honestly? it's giving "niche but iconic." it's a section 4 kernel interfaces manual, so like — hardware driver territory. buckle up, we're learning ✨

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🌸 NAME 🌸

dwmshc — the Synopsys DesignWare Mobile Storage Host Controller. yes that is a whole mouthful, no I did not make it up, that's literally its government name 💀

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✨ SYNOPSIS ✨

like, the whole vibe in two lines:

dwmshc* at fdt?
sdmmc* at dwmshc?

that's it. that's the configuration. short and slay 🫶

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💖 DESCRIPTION 💖

so the dwmshc driver is out here providing support for the Synopsys DesignWare Mobile Storage Host Controller core. and like — where does this core actually live? on the Rockchip RK3528, the RK3566/RK3568 and the RK3588 SoCs, where it's the eMMC controller. main character energy, fr fr 👑

now here's the tea ☕ — the Synopsys DesignWare Mobile Storage Host Controller core does implement the SD Host Controller Standard Simplified Specification, which sounds very official and it is, BUT (and this is the important part, don't skip it 🫵) it requires non-standard support for high clock rates. so. yeah. special handling. noted. lowkey a diva about clocks 💅

and then the sdmmc(4) subsystem is the one doing all the actual work of performing SD/MMC transactions, so it can communicate with all the MMC/SD/SDIO devices connected to the controller. it's the social butterfly of the operation, connecting everyone 🦋

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🎀 SEE ALSO 🎀

go read these next, they're all linked in the group chat:

• intro(4)
• sdhc(4)
• sdmmc(4)

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🌈 HISTORY 🌈

the dwmshc driver first appeared in OpenBSD 7.4. a legend was born, periodt ⭐

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okay that's the whole page, you ate that ngl 🍓 and for the cute sign-off — this lil beauty comes to you from Debian, dated April 8, 2026. mwah 💋 see you in the next manpage bestie 🧚💜