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1// SPDX-License-Identifier: GPL-2.02/*3 * non-coherent cache functions for Andes AX45MP4 *5 * Copyright (C) 2023 Renesas Electronics Corp.6 */7 8#include <linux/cacheflush.h>9#include <linux/cacheinfo.h>10#include <linux/dma-direction.h>11#include <linux/of_address.h>12#include <linux/of_platform.h>13 14#include <asm/dma-noncoherent.h>15 16/* L2 cache registers */17#define AX45MP_L2C_REG_CTL_OFFSET		0x818 19#define AX45MP_L2C_REG_C0_CMD_OFFSET		0x4020#define AX45MP_L2C_REG_C0_ACC_OFFSET		0x4821#define AX45MP_L2C_REG_STATUS_OFFSET		0x8022 23/* D-cache operation */24#define AX45MP_CCTL_L1D_VA_INVAL		0 /* Invalidate an L1 cache entry */25#define AX45MP_CCTL_L1D_VA_WB			1 /* Write-back an L1 cache entry */26 27/* L2 CCTL status */28#define AX45MP_CCTL_L2_STATUS_IDLE		029 30/* L2 CCTL status cores mask */31#define AX45MP_CCTL_L2_STATUS_C0_MASK		0xf32 33/* L2 cache operation */34#define AX45MP_CCTL_L2_PA_INVAL			0x8 /* Invalidate an L2 cache entry */35#define AX45MP_CCTL_L2_PA_WB			0x9 /* Write-back an L2 cache entry */36 37#define AX45MP_L2C_REG_PER_CORE_OFFSET		0x1038#define AX45MP_CCTL_L2_STATUS_PER_CORE_OFFSET	439 40#define AX45MP_L2C_REG_CN_CMD_OFFSET(n)	\41	(AX45MP_L2C_REG_C0_CMD_OFFSET + ((n) * AX45MP_L2C_REG_PER_CORE_OFFSET))42#define AX45MP_L2C_REG_CN_ACC_OFFSET(n)	\43	(AX45MP_L2C_REG_C0_ACC_OFFSET + ((n) * AX45MP_L2C_REG_PER_CORE_OFFSET))44#define AX45MP_CCTL_L2_STATUS_CN_MASK(n)	\45	(AX45MP_CCTL_L2_STATUS_C0_MASK << ((n) * AX45MP_CCTL_L2_STATUS_PER_CORE_OFFSET))46 47#define AX45MP_CCTL_REG_UCCTLBEGINADDR_NUM	0x80b48#define AX45MP_CCTL_REG_UCCTLCOMMAND_NUM	0x80c49 50#define AX45MP_CACHE_LINE_SIZE			6451 52struct ax45mp_priv {53	void __iomem *l2c_base;54	u32 ax45mp_cache_line_size;55};56 57static struct ax45mp_priv ax45mp_priv;58 59/* L2 Cache operations */60static inline uint32_t ax45mp_cpu_l2c_get_cctl_status(void)61{62	return readl(ax45mp_priv.l2c_base + AX45MP_L2C_REG_STATUS_OFFSET);63}64 65static void ax45mp_cpu_cache_operation(unsigned long start, unsigned long end,66				       unsigned int l1_op, unsigned int l2_op)67{68	unsigned long line_size = ax45mp_priv.ax45mp_cache_line_size;69	void __iomem *base = ax45mp_priv.l2c_base;70	int mhartid = smp_processor_id();71	unsigned long pa;72 73	while (end > start) {74		csr_write(AX45MP_CCTL_REG_UCCTLBEGINADDR_NUM, start);75		csr_write(AX45MP_CCTL_REG_UCCTLCOMMAND_NUM, l1_op);76 77		pa = virt_to_phys((void *)start);78		writel(pa, base + AX45MP_L2C_REG_CN_ACC_OFFSET(mhartid));79		writel(l2_op, base + AX45MP_L2C_REG_CN_CMD_OFFSET(mhartid));80		while ((ax45mp_cpu_l2c_get_cctl_status() &81			AX45MP_CCTL_L2_STATUS_CN_MASK(mhartid)) !=82			AX45MP_CCTL_L2_STATUS_IDLE)83			;84 85		start += line_size;86	}87}88 89/* Write-back L1 and L2 cache entry */90static inline void ax45mp_cpu_dcache_wb_range(unsigned long start, unsigned long end)91{92	ax45mp_cpu_cache_operation(start, end, AX45MP_CCTL_L1D_VA_WB,93				   AX45MP_CCTL_L2_PA_WB);94}95 96/* Invalidate the L1 and L2 cache entry */97static inline void ax45mp_cpu_dcache_inval_range(unsigned long start, unsigned long end)98{99	ax45mp_cpu_cache_operation(start, end, AX45MP_CCTL_L1D_VA_INVAL,100				   AX45MP_CCTL_L2_PA_INVAL);101}102 103static void ax45mp_dma_cache_inv(phys_addr_t paddr, size_t size)104{105	unsigned long start = (unsigned long)phys_to_virt(paddr);106	unsigned long end = start + size;107	unsigned long line_size;108	unsigned long flags;109 110	if (unlikely(start == end))111		return;112 113	line_size = ax45mp_priv.ax45mp_cache_line_size;114 115	start = start & (~(line_size - 1));116	end = ((end + line_size - 1) & (~(line_size - 1)));117 118	local_irq_save(flags);119 120	ax45mp_cpu_dcache_inval_range(start, end);121 122	local_irq_restore(flags);123}124 125static void ax45mp_dma_cache_wback(phys_addr_t paddr, size_t size)126{127	unsigned long start = (unsigned long)phys_to_virt(paddr);128	unsigned long end = start + size;129	unsigned long line_size;130	unsigned long flags;131 132	if (unlikely(start == end))133		return;134 135	line_size = ax45mp_priv.ax45mp_cache_line_size;136	start = start & (~(line_size - 1));137	end = ((end + line_size - 1) & (~(line_size - 1)));138	local_irq_save(flags);139	ax45mp_cpu_dcache_wb_range(start, end);140	local_irq_restore(flags);141}142 143static void ax45mp_dma_cache_wback_inv(phys_addr_t paddr, size_t size)144{145	ax45mp_dma_cache_wback(paddr, size);146	ax45mp_dma_cache_inv(paddr, size);147}148 149static int ax45mp_get_l2_line_size(struct device_node *np)150{151	int ret;152 153	ret = of_property_read_u32(np, "cache-line-size", &ax45mp_priv.ax45mp_cache_line_size);154	if (ret) {155		pr_err("Failed to get cache-line-size, defaulting to 64 bytes\n");156		return ret;157	}158 159	if (ax45mp_priv.ax45mp_cache_line_size != AX45MP_CACHE_LINE_SIZE) {160		pr_err("Expected cache-line-size to be 64 bytes (found:%u)\n",161		       ax45mp_priv.ax45mp_cache_line_size);162		return -EINVAL;163	}164 165	return 0;166}167 168static const struct riscv_nonstd_cache_ops ax45mp_cmo_ops __initdata = {169	.wback = &ax45mp_dma_cache_wback,170	.inv = &ax45mp_dma_cache_inv,171	.wback_inv = &ax45mp_dma_cache_wback_inv,172};173 174static const struct of_device_id ax45mp_cache_ids[] = {175	{ .compatible = "andestech,ax45mp-cache" },176	{ /* sentinel */ }177};178 179static int __init ax45mp_cache_init(void)180{181	struct device_node *np;182	struct resource res;183	int ret;184 185	np = of_find_matching_node(NULL, ax45mp_cache_ids);186	if (!of_device_is_available(np))187		return -ENODEV;188 189	ret = of_address_to_resource(np, 0, &res);190	if (ret)191		return ret;192 193	/*194	 * If IOCP is present on the Andes AX45MP core riscv_cbom_block_size195	 * will be 0 for sure, so we can definitely rely on it. If196	 * riscv_cbom_block_size = 0 we don't need to handle CMO using SW any197	 * more so we just return success here and only if its being set we198	 * continue further in the probe path.199	 */200	if (!riscv_cbom_block_size)201		return 0;202 203	ax45mp_priv.l2c_base = ioremap(res.start, resource_size(&res));204	if (!ax45mp_priv.l2c_base)205		return -ENOMEM;206 207	ret = ax45mp_get_l2_line_size(np);208	if (ret) {209		iounmap(ax45mp_priv.l2c_base);210		return ret;211	}212 213	riscv_noncoherent_register_cache_ops(&ax45mp_cmo_ops);214 215	return 0;216}217early_initcall(ax45mp_cache_init);218