STRUCT GDSC(9)

👑 struct gdsc(9) 👑

okay so bestie, welcome to the Kernel API Manual — yes, that Kernel API Manual — and today's main character is struct gdsc, which stands for Globally Distributed Switch Controller. that's the whole name, no notes. it's giving power-management royalty and honestly? iconic. 🎀

✨ SYNOPSIS ✨

like, here's the whole vibe, character for character. do not touch the #defines, they are load-bearing:

struct gdsc {
    struct generic_pm_domain        pd;
    struct generic_pm_domain        *parent;
    struct regmap                   *regmap;
    unsigned int                    gdscr;
    unsigned int                    collapse_ctrl;
    unsigned int                    collapse_mask;
    unsigned int                    gds_hw_ctrl;
    unsigned int                    clamp_io_ctrl;
    unsigned int                    *cxcs;
    unsigned int                    cxc_count;
    unsigned int                    en_rest_wait_val;
    unsigned int                    en_few_wait_val;
    unsigned int                    clk_dis_wait_val;
    const u8                        pwrsts;
  #define PWRSTS_OFF              BIT(0);
  #define PWRSTS_RET              BIT(1);
  #define PWRSTS_ON               BIT(2);
  #define PWRSTS_OFF_ON           (PWRSTS_OFF | PWRSTS_ON);
  #define PWRSTS_RET_ON           (PWRSTS_RET | PWRSTS_ON);
    const u16                       flags;
  #define VOTABLE         BIT(0);
  #define CLAMP_IO        BIT(1);
  #define HW_CTRL         BIT(2);
  #define SW_RESET        BIT(3);
  #define AON_RESET       BIT(4);
  #define POLL_CFG_GDSCR  BIT(5);
  #define ALWAYS_ON       BIT(6);
  #define RETAIN_FF_ENABLE        BIT(7);
  #define NO_RET_PERIPH   BIT(8);
  #define HW_CTRL_TRIGGER BIT(9);
    struct reset_controller_dev     *rcdev;
    unsigned int                    *resets;
    unsigned int                    reset_count;
    const char                      *supply;
    struct regulator                *rsupply;
    bool needs_icc;
    unsigned int                    icc_path_index;
    struct icc_path                 *icc_path;
};

💅 Members 💅

bestie these are the fields, and every single one of them matters, okay? no skipping:

• pd — the generic power domain. it's the whole personality of the struct, lowkey.
• regmap — the regmap for MMIO accesses. that's how we vibe with the hardware. 💜
• gdscr — the gsdc control register. (yes, spelled gsdc right there in the register description. we're just the messenger 🫶)
• collapse_ctrl — the APCS collapse-vote register.
• collapse_mask — the APCS collapse-vote mask. it masks the vote. that's the whole job.
• gds_hw_ctrl — the gds_hw_ctrl register. name literally says it all ngl.
• cxcs — offsets of branch registers to toggle mem/periph bits in.
• cxc_count — number of cxcs. bestie counts her offsets. ✨
• en_rest_wait_val — transition delay value for receiving enr ack signal.
• en_few_wait_val — transition delay value for receiving enf ack signal.
• clk_dis_wait_val — transition delay value for halting clock.
• pwrsts — possible powerdomain power states. (see all the PWRSTS_* bits up there ⬆️)
• rcdev — the reset controller.
• resets — ids of resets associated with this gdsc.
• reset_count — number of resets.

ngl the synopsis has a few more fields than the Members list spells out — parent, clamp_io_ctrl, supply, rsupply, needs_icc, icc_path_index, icc_path — and no, I'm not gonna gaslight you about it. the struct is the struct. 🌸

🌈 SEE ALSO 🌈

• the Kernel file ./drivers/clk/qcom/gdsc.h — go read it, iykyk 🔥

okay that's the page!! tysm for reading all the way through, you ate that fr fr 💖 this drop comes straight from ./drivers/clk/qcom, dated October 2026 — so go forth, reference struct gdsc(9) responsibly, and remember: power domains are temporary, slay is forever. 🦋✨