Merge tag 'riscv-cache-for-v6.11' of...

Merge tag 'riscv-cache-for-v6.11' of https://git.kernel.org/pub/scm/linux/kernel/git/conor/linux into soc/drivers

RISC-V cache drivers for v6.11

StarFive:
A new driver for the cache controller on the jh8100, which didn't
implement Zicbom and thus needs an implementation of non-standard cache
management operations.
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>

* tag 'riscv-cache-for-v6.11' of https://git.kernel.org/pub/scm/linux/kernel/git/conor/linux:
  MAINTAINERS: add microchip soc binding directory to microchip soc driver entry
  MAINTAINERS: add cache binding directory to cache driver entry
  cache: Add StarFive StarLink cache management
  dt-bindings: cache: Add docs for StarFive Starlink cache controller

Link: https://lore.kernel.org/r/20240707-whoever-undesired-c5f6e96ae403@spudSigned-off-by: Arnd Bergmann <arnd@arndb.de>

Documentation/devicetree/bindings/cache/starfive,jh8100-starlink-cache.yaml

+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/cache/starfive,jh8100-starlink-cache.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: StarFive StarLink Cache Controller
+
+maintainers:
+  - Joshua Yeong <joshua.yeong@starfivetech.com>
+
+description:
+  StarFive's StarLink Cache Controller manages the L3 cache shared between
+  clusters of CPU cores. The cache driver enables RISC-V non-standard cache
+  management as an alternative to instructions in the RISC-V Zicbom extension.
+
+allOf:
+  - $ref: /schemas/cache-controller.yaml#
+
+# We need a select here so we don't match all nodes with 'cache'
+select:
+  properties:
+    compatible:
+      contains:
+        enum:
+          - starfive,jh8100-starlink-cache
+
+  required:
+    - compatible
+
+properties:
+  compatible:
+    items:
+      - const: starfive,jh8100-starlink-cache
+      - const: cache
+
+  reg:
+    maxItems: 1
+
+unevaluatedProperties: false
+
+required:
+  - compatible
+  - reg
+  - cache-block-size
+  - cache-level
+  - cache-sets
+  - cache-size
+  - cache-unified
+
+examples:
+  - |
+      soc {
+        #address-cells = <2>;
+        #size-cells = <2>;
+
+        cache-controller@15000000 {
+          compatible = "starfive,jh8100-starlink-cache", "cache";
+          reg = <0x0 0x15000000 0x0 0x278>;
+          cache-block-size = <64>;
+          cache-level = <3>;
+          cache-sets = <8192>;
+          cache-size = <0x400000>;
+          cache-unified;
+        };
+      };

MAINTAINERS

@@ -14852,6 +14852,7 @@ MICROCHIP SOC DRIVERS
 M:	Conor Dooley <conor@kernel.org>
 S:	Supported
 T:	git https://git.kernel.org/pub/scm/linux/kernel/git/conor/linux.git/
+F:	Documentation/devicetree/bindings/soc/microchip/
 F:	drivers/soc/microchip/
 
 MICROCHIP SPI DRIVER
@@ -21287,6 +21288,7 @@ M:	Conor Dooley <conor@kernel.org>
 L:	linux-riscv@lists.infradead.org
 S:	Maintained
 T:	git https://git.kernel.org/pub/scm/linux/kernel/git/conor/linux.git/
+F:	Documentation/devicetree/bindings/cache/
 F:	drivers/cache
 
 STARFIRE/DURALAN NETWORK DRIVER

drivers/cache/Kconfig

@@ -14,4 +14,13 @@ config SIFIVE_CCACHE
 	help
 	  Support for the composable cache controller on SiFive platforms.
 
+config STARFIVE_STARLINK_CACHE
+	bool "StarFive StarLink Cache controller"
+	depends on RISCV
+	depends on ARCH_STARFIVE
+	select RISCV_DMA_NONCOHERENT
+	select RISCV_NONSTANDARD_CACHE_OPS
+	help
+	  Support for the StarLink cache controller IP from StarFive.
+
 endmenu

drivers/cache/Makefile

 # SPDX-License-Identifier: GPL-2.0
 
-obj-$(CONFIG_AX45MP_L2_CACHE)	+= ax45mp_cache.o
-obj-$(CONFIG_SIFIVE_CCACHE)	+= sifive_ccache.o
+obj-$(CONFIG_AX45MP_L2_CACHE)		+= ax45mp_cache.o
+obj-$(CONFIG_SIFIVE_CCACHE)		+= sifive_ccache.o
+obj-$(CONFIG_STARFIVE_STARLINK_CACHE)	+= starfive_starlink_cache.o

drivers/cache/starfive_starlink_cache.c

+// 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);