omap4_pwrdm...ev_mem_pwrst(9)

💅 omap4_pwrdm...ev_mem_pwrst(9) 💅

okay so bestie, we're in the Kernel API Manual today, and this page is literally about omap4_pwrdm_read_prev_mem_pwrst — say that five times fast, i dare you 🫶

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✨ NAME ✨

omap4_pwrdm_read_prev_mem_pwrst — reads the previous memory powerstate

like, it goes and finds out what the memory powerstate was before. nostalgia but for hardware 💭

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🌸 SYNOPSIS 🌸

int omap4_pwrdm_read_prev_mem_pwrst (struct powerdomain *pwrdm , u8 bank
);

so it returns an int, takes a struct powerdomain *pwrdm, and a u8 bank. that's the whole vibe check ✨

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🎀 ARGUMENTS 🎀

• pwrdm — a struct powerdomain * that you wanna read the mem powerstate for. it's giving "point me at the domain, bestie" 👉
• bank — the memory bank index. yes queen, you gotta say which bank 🏦

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🦋 DESCRIPTION 🦋

so here's the tea ☕ — this function reads the previous memory powerstate for a powerdomain. but it's not just a straight lookup, okay? it has layers. main character energy fr fr.

to figure out the previous memory powerstate, it first checks the previous powerstate for the domain. then:

• if that previous state was OFF — oop, the logic has been lost 😭
• if the previous state was RETENTION, then it reads the setting for the next memory retention state to see the actual value. detective work, we love to see it 🔍
• in every other case, the logic is retained. slay 💅

and it returns either PWRDM_POWER_OFF or PWRDM_POWER_RET, depending on whether the logic was retained or not. two outcomes, no in-between, periodt ✨

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👑 SEE ALSO 👑

the kernel file for this one is literally:

./arch/arm/mach-omap2/prm44xx.c

and here's the whole friend group, all together, no cap 🫶

• omap44xx_prm_read_pending_irqs(9)
• omap44xx_prm_ocp_barrier(9)
• omap44xx_prm_save_and_clear_irqen(9)
• omap44xx_prm_restore_irqen(9)
• omap44xx_prm_reconfigure_io_chain(9)
• omap44xx_prm_enable_io_wakeup(9)
• omap44xx_prm_read_reset_sources(9)
• omap44xx_prm_was_any_context_lost_old(9)
• omap44xx_prm_clear_context_loss_flags_old(9)
• omap4_pwrdm_read_prev_logic_pwrst(9)
• omap4_pwrdm_save_context(9)
• omap4_pwrdm_restore_context(9)

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ngl bestie, if you're reading this at 3am debugging power domains, drink some water and take a lil break 💜

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and that's the page!! 🎀 it lives over in ./arch/arm/mach-omap2, dated October 2026, and it's filed under omap4_pwrdm...ev_mem_pwrst(9) in the Kernel API Manual — mwah, go read your kernel source, ily, bye 💖✨