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path: root/drivers/cache/starfive_starlink_cache.c
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Diffstat (limited to 'drivers/cache/starfive_starlink_cache.c')
-rw-r--r--drivers/cache/starfive_starlink_cache.c130
1 files changed, 130 insertions, 0 deletions
diff --git a/drivers/cache/starfive_starlink_cache.c b/drivers/cache/starfive_starlink_cache.c
new file mode 100644
index 000000000000..24c7d078ca22
--- /dev/null
+++ b/drivers/cache/starfive_starlink_cache.c
@@ -0,0 +1,130 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Cache Management Operations for StarFive's Starlink cache controller
+ *
+ * Copyright (C) 2024 Shanghai StarFive Technology Co., Ltd.
+ *
+ * Author: Joshua Yeong <joshua.yeong@starfivetech.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/cacheflush.h>
+#include <linux/iopoll.h>
+#include <linux/of_address.h>
+
+#include <asm/dma-noncoherent.h>
+
+#define STARLINK_CACHE_FLUSH_START_ADDR 0x0
+#define STARLINK_CACHE_FLUSH_END_ADDR 0x8
+#define STARLINK_CACHE_FLUSH_CTL 0x10
+#define STARLINK_CACHE_ALIGN 0x40
+
+#define STARLINK_CACHE_ADDRESS_RANGE_MASK GENMASK(39, 0)
+#define STARLINK_CACHE_FLUSH_CTL_MODE_MASK GENMASK(2, 1)
+#define STARLINK_CACHE_FLUSH_CTL_ENABLE_MASK BIT(0)
+
+#define STARLINK_CACHE_FLUSH_CTL_CLEAN_INVALIDATE 0
+#define STARLINK_CACHE_FLUSH_CTL_MAKE_INVALIDATE 1
+#define STARLINK_CACHE_FLUSH_CTL_CLEAN_SHARED 2
+#define STARLINK_CACHE_FLUSH_POLL_DELAY_US 1
+#define STARLINK_CACHE_FLUSH_TIMEOUT_US 5000000
+
+static void __iomem *starlink_cache_base;
+
+static void starlink_cache_flush_complete(void)
+{
+ volatile void __iomem *ctl = starlink_cache_base + STARLINK_CACHE_FLUSH_CTL;
+ u64 v;
+ int ret;
+
+ ret = readq_poll_timeout_atomic(ctl, v, !(v & STARLINK_CACHE_FLUSH_CTL_ENABLE_MASK),
+ STARLINK_CACHE_FLUSH_POLL_DELAY_US,
+ STARLINK_CACHE_FLUSH_TIMEOUT_US);
+ if (ret)
+ WARN(1, "StarFive Starlink cache flush operation timeout\n");
+}
+
+static void starlink_cache_dma_cache_wback(phys_addr_t paddr, unsigned long size)
+{
+ writeq(FIELD_PREP(STARLINK_CACHE_ADDRESS_RANGE_MASK, paddr),
+ starlink_cache_base + STARLINK_CACHE_FLUSH_START_ADDR);
+ writeq(FIELD_PREP(STARLINK_CACHE_ADDRESS_RANGE_MASK, paddr + size),
+ starlink_cache_base + STARLINK_CACHE_FLUSH_END_ADDR);
+
+ mb();
+ writeq(FIELD_PREP(STARLINK_CACHE_FLUSH_CTL_MODE_MASK,
+ STARLINK_CACHE_FLUSH_CTL_CLEAN_SHARED),
+ starlink_cache_base + STARLINK_CACHE_FLUSH_CTL);
+
+ starlink_cache_flush_complete();
+}
+
+static void starlink_cache_dma_cache_invalidate(phys_addr_t paddr, unsigned long size)
+{
+ writeq(FIELD_PREP(STARLINK_CACHE_ADDRESS_RANGE_MASK, paddr),
+ starlink_cache_base + STARLINK_CACHE_FLUSH_START_ADDR);
+ writeq(FIELD_PREP(STARLINK_CACHE_ADDRESS_RANGE_MASK, paddr + size),
+ starlink_cache_base + STARLINK_CACHE_FLUSH_END_ADDR);
+
+ mb();
+ writeq(FIELD_PREP(STARLINK_CACHE_FLUSH_CTL_MODE_MASK,
+ STARLINK_CACHE_FLUSH_CTL_MAKE_INVALIDATE),
+ starlink_cache_base + STARLINK_CACHE_FLUSH_CTL);
+
+ starlink_cache_flush_complete();
+}
+
+static void starlink_cache_dma_cache_wback_inv(phys_addr_t paddr, unsigned long size)
+{
+ writeq(FIELD_PREP(STARLINK_CACHE_ADDRESS_RANGE_MASK, paddr),
+ starlink_cache_base + STARLINK_CACHE_FLUSH_START_ADDR);
+ writeq(FIELD_PREP(STARLINK_CACHE_ADDRESS_RANGE_MASK, paddr + size),
+ starlink_cache_base + STARLINK_CACHE_FLUSH_END_ADDR);
+
+ mb();
+ writeq(FIELD_PREP(STARLINK_CACHE_FLUSH_CTL_MODE_MASK,
+ STARLINK_CACHE_FLUSH_CTL_CLEAN_INVALIDATE),
+ starlink_cache_base + STARLINK_CACHE_FLUSH_CTL);
+
+ starlink_cache_flush_complete();
+}
+
+static const struct riscv_nonstd_cache_ops starlink_cache_ops = {
+ .wback = &starlink_cache_dma_cache_wback,
+ .inv = &starlink_cache_dma_cache_invalidate,
+ .wback_inv = &starlink_cache_dma_cache_wback_inv,
+};
+
+static const struct of_device_id starlink_cache_ids[] = {
+ { .compatible = "starfive,jh8100-starlink-cache" },
+ { /* sentinel */ }
+};
+
+static int __init starlink_cache_init(void)
+{
+ struct device_node *np;
+ u32 block_size;
+ int ret;
+
+ np = of_find_matching_node(NULL, starlink_cache_ids);
+ if (!of_device_is_available(np))
+ return -ENODEV;
+
+ ret = of_property_read_u32(np, "cache-block-size", &block_size);
+ if (ret)
+ return ret;
+
+ if (block_size % STARLINK_CACHE_ALIGN)
+ return -EINVAL;
+
+ starlink_cache_base = of_iomap(np, 0);
+ if (!starlink_cache_base)
+ return -ENOMEM;
+
+ riscv_cbom_block_size = block_size;
+ riscv_noncoherent_supported();
+ riscv_noncoherent_register_cache_ops(&starlink_cache_ops);
+
+ return 0;
+}
+arch_initcall(starlink_cache_init);