// SPDX-License-Identifier: GPL-2.0-only /* * Au1300 media block power gating (VSS) * * This is a stop-gap solution until I have the clock framework integration * ready. This stuff here really must be handled transparently when clocks * for various media blocks are enabled/disabled. */ #include <linux/export.h> #include <linux/spinlock.h> #include <asm/mach-au1x00/au1000.h> #define VSS_GATE 0x00 /* gate wait timers */ #define VSS_CLKRST 0x04 /* clock/block control */ #define VSS_FTR 0x08 /* footers */ #define VSS_ADDR(blk) (KSEG1ADDR(AU1300_VSS_PHYS_ADDR) + (blk * 0x0c)) static DEFINE_SPINLOCK(au1300_vss_lock); /* enable a block as outlined in the databook */ static inline void __enable_block(int block) { void __iomem *base = (void __iomem *)VSS_ADDR(block); __raw_writel(3, base + VSS_CLKRST); /* enable clock, assert reset */ wmb(); __raw_writel(0x01fffffe, base + VSS_GATE); /* maximum setup time */ wmb(); /* enable footers in sequence */ __raw_writel(0x01, base + VSS_FTR); wmb(); __raw_writel(0x03, base + VSS_FTR); wmb(); __raw_writel(0x07, base + VSS_FTR); wmb(); __raw_writel(0x0f, base + VSS_FTR); wmb(); __raw_writel(0x01ffffff, base + VSS_GATE); /* start FSM too */ wmb(); __raw_writel(2, base + VSS_CLKRST); /* deassert reset */ wmb(); __raw_writel(0x1f, base + VSS_FTR); /* enable isolation cells */ wmb(); } /* disable a block as outlined in the databook */ static inline void __disable_block(int block) { void __iomem *base = (void __iomem *)VSS_ADDR(block); __raw_writel(0x0f, base + VSS_FTR); /* disable isolation cells */ wmb(); __raw_writel(0, base + VSS_GATE); /* disable FSM */ wmb(); __raw_writel(3, base + VSS_CLKRST); /* assert reset */ wmb(); __raw_writel(1, base + VSS_CLKRST); /* disable clock */ wmb(); __raw_writel(0, base + VSS_FTR); /* disable all footers */ wmb(); } void au1300_vss_block_control(int block, int enable) { unsigned long flags; if (alchemy_get_cputype() != ALCHEMY_CPU_AU1300) return; /* only one block at a time */ spin_lock_irqsave(&au1300_vss_lock, flags); if (enable) __enable_block(block); else __disable_block(block); spin_unlock_irqrestore(&au1300_vss_lock, flags); } EXPORT_SYMBOL_GPL(au1300_vss_block_control);