From 119e9db233ad0f4cbd4cfb9f9385a7bca378b37d Mon Sep 17 00:00:00 2001 From: Zeng Chi Date: Mon, 21 Sep 2026 18:24:42 +0800 Subject: KVM: Don't pre-reserve xarray entries when storing empty/NULL attributes Skip the xarray reservation loop when clearing all memory attributes, as storing NULL only erases the entry and never needs to allocate, so no reservation (and no cleanup of a failed one) is required in that case. Suggested-by: Sean Christopherson Cc: David Ballesteros Signed-off-by: Zeng Chi Link: https://patch.msgid.link/20260921102442.1232375-1-zeng_chi911@163.com [sean: split to separate patch] Signed-off-by: Sean Christopherson --- drivers/cache/ax45mp_cache.c | 217 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 217 insertions(+) create mode 100644 drivers/cache/ax45mp_cache.c (limited to 'drivers/cache/ax45mp_cache.c') diff --git a/drivers/cache/ax45mp_cache.c b/drivers/cache/ax45mp_cache.c new file mode 100644 index 000000000..934c5087e --- /dev/null +++ b/drivers/cache/ax45mp_cache.c @@ -0,0 +1,217 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * non-coherent cache functions for Andes AX45MP + * + * Copyright (C) 2023 Renesas Electronics Corp. + */ + +#include +#include +#include +#include +#include + +#include + +/* L2 cache registers */ +#define AX45MP_L2C_REG_CTL_OFFSET 0x8 + +#define AX45MP_L2C_REG_C0_CMD_OFFSET 0x40 +#define AX45MP_L2C_REG_C0_ACC_OFFSET 0x48 +#define AX45MP_L2C_REG_STATUS_OFFSET 0x80 + +/* D-cache operation */ +#define AX45MP_CCTL_L1D_VA_INVAL 0 /* Invalidate an L1 cache entry */ +#define AX45MP_CCTL_L1D_VA_WB 1 /* Write-back an L1 cache entry */ + +/* L2 CCTL status */ +#define AX45MP_CCTL_L2_STATUS_IDLE 0 + +/* L2 CCTL status cores mask */ +#define AX45MP_CCTL_L2_STATUS_C0_MASK 0xf + +/* L2 cache operation */ +#define AX45MP_CCTL_L2_PA_INVAL 0x8 /* Invalidate an L2 cache entry */ +#define AX45MP_CCTL_L2_PA_WB 0x9 /* Write-back an L2 cache entry */ + +#define AX45MP_L2C_REG_PER_CORE_OFFSET 0x10 +#define AX45MP_CCTL_L2_STATUS_PER_CORE_OFFSET 4 + +#define AX45MP_L2C_REG_CN_CMD_OFFSET(n) \ + (AX45MP_L2C_REG_C0_CMD_OFFSET + ((n) * AX45MP_L2C_REG_PER_CORE_OFFSET)) +#define AX45MP_L2C_REG_CN_ACC_OFFSET(n) \ + (AX45MP_L2C_REG_C0_ACC_OFFSET + ((n) * AX45MP_L2C_REG_PER_CORE_OFFSET)) +#define AX45MP_CCTL_L2_STATUS_CN_MASK(n) \ + (AX45MP_CCTL_L2_STATUS_C0_MASK << ((n) * AX45MP_CCTL_L2_STATUS_PER_CORE_OFFSET)) + +#define AX45MP_CCTL_REG_UCCTLBEGINADDR_NUM 0x80b +#define AX45MP_CCTL_REG_UCCTLCOMMAND_NUM 0x80c + +#define AX45MP_CACHE_LINE_SIZE 64 + +struct ax45mp_priv { + void __iomem *l2c_base; + u32 ax45mp_cache_line_size; +}; + +static struct ax45mp_priv ax45mp_priv; + +/* L2 Cache operations */ +static inline uint32_t ax45mp_cpu_l2c_get_cctl_status(void) +{ + return readl(ax45mp_priv.l2c_base + AX45MP_L2C_REG_STATUS_OFFSET); +} + +static void ax45mp_cpu_cache_operation(unsigned long start, unsigned long end, + unsigned int l1_op, unsigned int l2_op) +{ + unsigned long line_size = ax45mp_priv.ax45mp_cache_line_size; + void __iomem *base = ax45mp_priv.l2c_base; + int mhartid = smp_processor_id(); + unsigned long pa; + + while (end > start) { + csr_write(AX45MP_CCTL_REG_UCCTLBEGINADDR_NUM, start); + csr_write(AX45MP_CCTL_REG_UCCTLCOMMAND_NUM, l1_op); + + pa = virt_to_phys((void *)start); + writel(pa, base + AX45MP_L2C_REG_CN_ACC_OFFSET(mhartid)); + writel(l2_op, base + AX45MP_L2C_REG_CN_CMD_OFFSET(mhartid)); + while ((ax45mp_cpu_l2c_get_cctl_status() & + AX45MP_CCTL_L2_STATUS_CN_MASK(mhartid)) != + AX45MP_CCTL_L2_STATUS_IDLE) + ; + + start += line_size; + } +} + +/* Write-back L1 and L2 cache entry */ +static inline void ax45mp_cpu_dcache_wb_range(unsigned long start, unsigned long end) +{ + ax45mp_cpu_cache_operation(start, end, AX45MP_CCTL_L1D_VA_WB, + AX45MP_CCTL_L2_PA_WB); +} + +/* Invalidate the L1 and L2 cache entry */ +static inline void ax45mp_cpu_dcache_inval_range(unsigned long start, unsigned long end) +{ + ax45mp_cpu_cache_operation(start, end, AX45MP_CCTL_L1D_VA_INVAL, + AX45MP_CCTL_L2_PA_INVAL); +} + +static void ax45mp_dma_cache_inv(phys_addr_t paddr, size_t size) +{ + unsigned long start = (unsigned long)phys_to_virt(paddr); + unsigned long end = start + size; + unsigned long line_size; + unsigned long flags; + + if (unlikely(start == end)) + return; + + line_size = ax45mp_priv.ax45mp_cache_line_size; + + start = start & (~(line_size - 1)); + end = ((end + line_size - 1) & (~(line_size - 1))); + + local_irq_save(flags); + + ax45mp_cpu_dcache_inval_range(start, end); + + local_irq_restore(flags); +} + +static void ax45mp_dma_cache_wback(phys_addr_t paddr, size_t size) +{ + unsigned long start = (unsigned long)phys_to_virt(paddr); + unsigned long end = start + size; + unsigned long line_size; + unsigned long flags; + + if (unlikely(start == end)) + return; + + line_size = ax45mp_priv.ax45mp_cache_line_size; + start = start & (~(line_size - 1)); + end = ((end + line_size - 1) & (~(line_size - 1))); + local_irq_save(flags); + ax45mp_cpu_dcache_wb_range(start, end); + local_irq_restore(flags); +} + +static void ax45mp_dma_cache_wback_inv(phys_addr_t paddr, size_t size) +{ + ax45mp_dma_cache_wback(paddr, size); + ax45mp_dma_cache_inv(paddr, size); +} + +static int ax45mp_get_l2_line_size(struct device_node *np) +{ + int ret; + + ret = of_property_read_u32(np, "cache-line-size", &ax45mp_priv.ax45mp_cache_line_size); + if (ret) { + pr_err("Failed to get cache-line-size, defaulting to 64 bytes\n"); + return ret; + } + + if (ax45mp_priv.ax45mp_cache_line_size != AX45MP_CACHE_LINE_SIZE) { + pr_err("Expected cache-line-size to be 64 bytes (found:%u)\n", + ax45mp_priv.ax45mp_cache_line_size); + return -EINVAL; + } + + return 0; +} + +static const struct riscv_nonstd_cache_ops ax45mp_cmo_ops __initdata = { + .wback = &ax45mp_dma_cache_wback, + .inv = &ax45mp_dma_cache_inv, + .wback_inv = &ax45mp_dma_cache_wback_inv, +}; + +static const struct of_device_id ax45mp_cache_ids[] = { + { .compatible = "andestech,ax45mp-cache" }, + { /* sentinel */ } +}; + +static int __init ax45mp_cache_init(void) +{ + struct resource res; + int ret; + + struct device_node *np __free(device_node) = + of_find_matching_node(NULL, ax45mp_cache_ids); + if (!of_device_is_available(np)) + return -ENODEV; + + ret = of_address_to_resource(np, 0, &res); + if (ret) + return ret; + + /* + * If IOCP is present on the Andes AX45MP core riscv_cbom_block_size + * will be 0 for sure, so we can definitely rely on it. If + * riscv_cbom_block_size = 0 we don't need to handle CMO using SW any + * more so we just return success here and only if its being set we + * continue further in the probe path. + */ + if (!riscv_cbom_block_size) + return 0; + + ax45mp_priv.l2c_base = ioremap(res.start, resource_size(&res)); + if (!ax45mp_priv.l2c_base) + return -ENOMEM; + + ret = ax45mp_get_l2_line_size(np); + if (ret) { + iounmap(ax45mp_priv.l2c_base); + return ret; + } + + riscv_noncoherent_register_cache_ops(&ax45mp_cmo_ops); + + return 0; +} +early_initcall(ax45mp_cache_init); -- cgit v1.3.1