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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /arch/mips/alchemy/common/vss.c | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/mips/alchemy/common/vss.c')
-rw-r--r-- | arch/mips/alchemy/common/vss.c | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/arch/mips/alchemy/common/vss.c b/arch/mips/alchemy/common/vss.c new file mode 100644 index 0000000000..3d0d468d93 --- /dev/null +++ b/arch/mips/alchemy/common/vss.c @@ -0,0 +1,85 @@ +// 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); |