projects / mirror_ubuntu-focal-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| 457c8996 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
| 809f36c6 ML |
2 | /* |
| 3 | * Au1300 media block power gating (VSS) | |
| 4 | * | |
| 5 | * This is a stop-gap solution until I have the clock framework integration | |
| 6 | * ready. This stuff here really must be handled transparently when clocks | |
| 7 | * for various media blocks are enabled/disabled. | |
| 8 | */ | |
| 9 | ||
| 26dd3e4f | 10 | #include <linux/export.h> |
| 809f36c6 ML |
11 | #include <linux/spinlock.h> |
| 12 | #include <asm/mach-au1x00/au1000.h> | |
| 13 | ||
| 14 | #define VSS_GATE 0x00 /* gate wait timers */ | |
| 15 | #define VSS_CLKRST 0x04 /* clock/block control */ | |
| 16 | #define VSS_FTR 0x08 /* footers */ | |
| 17 | ||
| 18 | #define VSS_ADDR(blk) (KSEG1ADDR(AU1300_VSS_PHYS_ADDR) + (blk * 0x0c)) | |
| 19 | ||
| 20 | static DEFINE_SPINLOCK(au1300_vss_lock); | |
| 21 | ||
| 22 | /* enable a block as outlined in the databook */ | |
| 23 | static inline void __enable_block(int block) | |
| 24 | { | |
| 25 | void __iomem *base = (void __iomem *)VSS_ADDR(block); | |
| 26 | ||
| 27 | __raw_writel(3, base + VSS_CLKRST); /* enable clock, assert reset */ | |
| 28 | wmb(); | |
| 29 | ||
| 30 | __raw_writel(0x01fffffe, base + VSS_GATE); /* maximum setup time */ | |
| 31 | wmb(); | |
| 32 | ||
| 33 | /* enable footers in sequence */ | |
| 34 | __raw_writel(0x01, base + VSS_FTR); | |
| 35 | wmb(); | |
| 36 | __raw_writel(0x03, base + VSS_FTR); | |
| 37 | wmb(); | |
| 38 | __raw_writel(0x07, base + VSS_FTR); | |
| 39 | wmb(); | |
| 40 | __raw_writel(0x0f, base + VSS_FTR); | |
| 41 | wmb(); | |
| 42 | ||
| 43 | __raw_writel(0x01ffffff, base + VSS_GATE); /* start FSM too */ | |
| 44 | wmb(); | |
| 45 | ||
| 46 | __raw_writel(2, base + VSS_CLKRST); /* deassert reset */ | |
| 47 | wmb(); | |
| 48 | ||
| 49 | __raw_writel(0x1f, base + VSS_FTR); /* enable isolation cells */ | |
| 50 | wmb(); | |
| 51 | } | |
| 52 | ||
| 53 | /* disable a block as outlined in the databook */ | |
| 54 | static inline void __disable_block(int block) | |
| 55 | { | |
| 56 | void __iomem *base = (void __iomem *)VSS_ADDR(block); | |
| 57 | ||
| 58 | __raw_writel(0x0f, base + VSS_FTR); /* disable isolation cells */ | |
| 59 | wmb(); | |
| 60 | __raw_writel(0, base + VSS_GATE); /* disable FSM */ | |
| 61 | wmb(); | |
| 62 | __raw_writel(3, base + VSS_CLKRST); /* assert reset */ | |
| 63 | wmb(); | |
| 64 | __raw_writel(1, base + VSS_CLKRST); /* disable clock */ | |
| 65 | wmb(); | |
| 66 | __raw_writel(0, base + VSS_FTR); /* disable all footers */ | |
| 67 | wmb(); | |
| 68 | } | |
| 69 | ||
| 70 | void au1300_vss_block_control(int block, int enable) | |
| 71 | { | |
| 72 | unsigned long flags; | |
| 73 | ||
| 74 | if (alchemy_get_cputype() != ALCHEMY_CPU_AU1300) | |
| 75 | return; | |
| 76 | ||
| 77 | /* only one block at a time */ | |
| 78 | spin_lock_irqsave(&au1300_vss_lock, flags); | |
| 79 | if (enable) | |
| 80 | __enable_block(block); | |
| 81 | else | |
| 82 | __disable_block(block); | |
| 83 | spin_unlock_irqrestore(&au1300_vss_lock, flags); | |
| 84 | } | |
| 85 | EXPORT_SYMBOL_GPL(au1300_vss_block_control); |