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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /drivers/soc/bcm/brcmstb/biuctrl.c | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/soc/bcm/brcmstb/biuctrl.c')
-rw-r--r-- | drivers/soc/bcm/brcmstb/biuctrl.c | 356 |
1 files changed, 356 insertions, 0 deletions
diff --git a/drivers/soc/bcm/brcmstb/biuctrl.c b/drivers/soc/bcm/brcmstb/biuctrl.c new file mode 100644 index 000000000..7f8dc302a --- /dev/null +++ b/drivers/soc/bcm/brcmstb/biuctrl.c @@ -0,0 +1,356 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Broadcom STB SoCs Bus Unit Interface controls + * + * Copyright (C) 2015, Broadcom Corporation + */ + +#define pr_fmt(fmt) "brcmstb: " KBUILD_MODNAME ": " fmt + +#include <linux/kernel.h> +#include <linux/io.h> +#include <linux/of_address.h> +#include <linux/syscore_ops.h> +#include <linux/soc/brcmstb/brcmstb.h> + +#define RACENPREF_MASK 0x3 +#define RACPREFINST_SHIFT 0 +#define RACENINST_SHIFT 2 +#define RACPREFDATA_SHIFT 4 +#define RACENDATA_SHIFT 6 +#define RAC_CPU_SHIFT 8 +#define RACCFG_MASK 0xff +#define DPREF_LINE_2_SHIFT 24 +#define DPREF_LINE_2_MASK 0xff + +/* Bitmask to enable instruction and data prefetching with a 256-bytes stride */ +#define RAC_DATA_INST_EN_MASK (1 << RACPREFINST_SHIFT | \ + RACENPREF_MASK << RACENINST_SHIFT | \ + 1 << RACPREFDATA_SHIFT | \ + RACENPREF_MASK << RACENDATA_SHIFT) + +#define CPU_CREDIT_REG_MCPx_WR_PAIRING_EN_MASK 0x70000000 +#define CPU_CREDIT_REG_MCPx_READ_CRED_MASK 0xf +#define CPU_CREDIT_REG_MCPx_WRITE_CRED_MASK 0xf +#define CPU_CREDIT_REG_MCPx_READ_CRED_SHIFT(x) ((x) * 8) +#define CPU_CREDIT_REG_MCPx_WRITE_CRED_SHIFT(x) (((x) * 8) + 4) + +#define CPU_MCP_FLOW_REG_MCPx_RDBUFF_CRED_SHIFT(x) ((x) * 8) +#define CPU_MCP_FLOW_REG_MCPx_RDBUFF_CRED_MASK 0xff + +#define CPU_WRITEBACK_CTRL_REG_WB_THROTTLE_THRESHOLD_MASK 0xf +#define CPU_WRITEBACK_CTRL_REG_WB_THROTTLE_TIMEOUT_MASK 0xf +#define CPU_WRITEBACK_CTRL_REG_WB_THROTTLE_TIMEOUT_SHIFT 4 +#define CPU_WRITEBACK_CTRL_REG_WB_THROTTLE_ENABLE BIT(8) + +static void __iomem *cpubiuctrl_base; +static bool mcp_wr_pairing_en; +static const int *cpubiuctrl_regs; + +enum cpubiuctrl_regs { + CPU_CREDIT_REG = 0, + CPU_MCP_FLOW_REG, + CPU_WRITEBACK_CTRL_REG, + RAC_CONFIG0_REG, + RAC_CONFIG1_REG, + NUM_CPU_BIUCTRL_REGS, +}; + +static inline u32 cbc_readl(int reg) +{ + int offset = cpubiuctrl_regs[reg]; + + if (offset == -1 || + (IS_ENABLED(CONFIG_CACHE_B15_RAC) && reg >= RAC_CONFIG0_REG)) + return (u32)-1; + + return readl_relaxed(cpubiuctrl_base + offset); +} + +static inline void cbc_writel(u32 val, int reg) +{ + int offset = cpubiuctrl_regs[reg]; + + if (offset == -1 || + (IS_ENABLED(CONFIG_CACHE_B15_RAC) && reg >= RAC_CONFIG0_REG)) + return; + + writel(val, cpubiuctrl_base + offset); +} + +static const int b15_cpubiuctrl_regs[] = { + [CPU_CREDIT_REG] = 0x184, + [CPU_MCP_FLOW_REG] = -1, + [CPU_WRITEBACK_CTRL_REG] = -1, + [RAC_CONFIG0_REG] = -1, + [RAC_CONFIG1_REG] = -1, +}; + +/* Odd cases, e.g: 7260A0 */ +static const int b53_cpubiuctrl_no_wb_regs[] = { + [CPU_CREDIT_REG] = 0x0b0, + [CPU_MCP_FLOW_REG] = 0x0b4, + [CPU_WRITEBACK_CTRL_REG] = -1, + [RAC_CONFIG0_REG] = 0x78, + [RAC_CONFIG1_REG] = 0x7c, +}; + +static const int b53_cpubiuctrl_regs[] = { + [CPU_CREDIT_REG] = 0x0b0, + [CPU_MCP_FLOW_REG] = 0x0b4, + [CPU_WRITEBACK_CTRL_REG] = 0x22c, + [RAC_CONFIG0_REG] = 0x78, + [RAC_CONFIG1_REG] = 0x7c, +}; + +static const int a72_cpubiuctrl_regs[] = { + [CPU_CREDIT_REG] = 0x18, + [CPU_MCP_FLOW_REG] = 0x1c, + [CPU_WRITEBACK_CTRL_REG] = 0x20, + [RAC_CONFIG0_REG] = 0x08, + [RAC_CONFIG1_REG] = 0x0c, +}; + +static int __init mcp_write_pairing_set(void) +{ + u32 creds = 0; + + if (!cpubiuctrl_base) + return -1; + + creds = cbc_readl(CPU_CREDIT_REG); + if (mcp_wr_pairing_en) { + pr_info("MCP: Enabling write pairing\n"); + cbc_writel(creds | CPU_CREDIT_REG_MCPx_WR_PAIRING_EN_MASK, + CPU_CREDIT_REG); + } else if (creds & CPU_CREDIT_REG_MCPx_WR_PAIRING_EN_MASK) { + pr_info("MCP: Disabling write pairing\n"); + cbc_writel(creds & ~CPU_CREDIT_REG_MCPx_WR_PAIRING_EN_MASK, + CPU_CREDIT_REG); + } else { + pr_info("MCP: Write pairing already disabled\n"); + } + + return 0; +} + +static const u32 a72_b53_mach_compat[] = { + 0x7211, + 0x7216, + 0x72164, + 0x72165, + 0x7255, + 0x7260, + 0x7268, + 0x7271, + 0x7278, +}; + +/* The read-ahead cache present in the Brahma-B53 CPU is a special piece of + * hardware after the integrated L2 cache of the B53 CPU complex whose purpose + * is to prefetch instruction and/or data with a line size of either 64 bytes + * or 256 bytes. The rationale is that the data-bus of the CPU interface is + * optimized for 256-byte transactions, and enabling the read-ahead cache + * provides a significant performance boost (typically twice the performance + * for a memcpy benchmark application). + * + * The read-ahead cache is transparent for Virtual Address cache maintenance + * operations: IC IVAU, DC IVAC, DC CVAC, DC CVAU and DC CIVAC. So no special + * handling is needed for the DMA API above and beyond what is included in the + * arm64 implementation. + * + * In addition, since the Point of Unification is typically between L1 and L2 + * for the Brahma-B53 processor no special read-ahead cache handling is needed + * for the IC IALLU and IC IALLUIS cache maintenance operations. + * + * However, it is not possible to specify the cache level (L3) for the cache + * maintenance instructions operating by set/way to operate on the read-ahead + * cache. The read-ahead cache will maintain coherency when inner cache lines + * are cleaned by set/way, but if it is necessary to invalidate inner cache + * lines by set/way to maintain coherency with system masters operating on + * shared memory that does not have hardware support for coherency, then it + * will also be necessary to explicitly invalidate the read-ahead cache. + */ +static void __init a72_b53_rac_enable_all(struct device_node *np) +{ + unsigned int cpu; + u32 enable = 0, pref_dist, shift; + + if (IS_ENABLED(CONFIG_CACHE_B15_RAC)) + return; + + if (WARN(num_possible_cpus() > 4, "RAC only supports 4 CPUs\n")) + return; + + pref_dist = cbc_readl(RAC_CONFIG1_REG); + for_each_possible_cpu(cpu) { + shift = cpu * RAC_CPU_SHIFT + RACPREFDATA_SHIFT; + enable |= RAC_DATA_INST_EN_MASK << (cpu * RAC_CPU_SHIFT); + if (cpubiuctrl_regs == a72_cpubiuctrl_regs) { + enable &= ~(RACENPREF_MASK << shift); + enable |= 3 << shift; + pref_dist |= 1 << (cpu + DPREF_LINE_2_SHIFT); + } + } + + cbc_writel(enable, RAC_CONFIG0_REG); + cbc_writel(pref_dist, RAC_CONFIG1_REG); + + pr_info("%pOF: Broadcom %s read-ahead cache\n", + np, cpubiuctrl_regs == a72_cpubiuctrl_regs ? + "Cortex-A72" : "Brahma-B53"); +} + +static void __init mcp_a72_b53_set(void) +{ + unsigned int i; + u32 reg; + + reg = brcmstb_get_family_id(); + + for (i = 0; i < ARRAY_SIZE(a72_b53_mach_compat); i++) { + if (BRCM_ID(reg) == a72_b53_mach_compat[i]) + break; + } + + if (i == ARRAY_SIZE(a72_b53_mach_compat)) + return; + + /* Set all 3 MCP interfaces to 8 credits */ + reg = cbc_readl(CPU_CREDIT_REG); + for (i = 0; i < 3; i++) { + reg &= ~(CPU_CREDIT_REG_MCPx_WRITE_CRED_MASK << + CPU_CREDIT_REG_MCPx_WRITE_CRED_SHIFT(i)); + reg &= ~(CPU_CREDIT_REG_MCPx_READ_CRED_MASK << + CPU_CREDIT_REG_MCPx_READ_CRED_SHIFT(i)); + reg |= 8 << CPU_CREDIT_REG_MCPx_WRITE_CRED_SHIFT(i); + reg |= 8 << CPU_CREDIT_REG_MCPx_READ_CRED_SHIFT(i); + } + cbc_writel(reg, CPU_CREDIT_REG); + + /* Max out the number of in-flight Jwords reads on the MCP interface */ + reg = cbc_readl(CPU_MCP_FLOW_REG); + for (i = 0; i < 3; i++) + reg |= CPU_MCP_FLOW_REG_MCPx_RDBUFF_CRED_MASK << + CPU_MCP_FLOW_REG_MCPx_RDBUFF_CRED_SHIFT(i); + cbc_writel(reg, CPU_MCP_FLOW_REG); + + /* Enable writeback throttling, set timeout to 128 cycles, 256 cycles + * threshold + */ + reg = cbc_readl(CPU_WRITEBACK_CTRL_REG); + reg |= CPU_WRITEBACK_CTRL_REG_WB_THROTTLE_ENABLE; + reg &= ~CPU_WRITEBACK_CTRL_REG_WB_THROTTLE_THRESHOLD_MASK; + reg &= ~(CPU_WRITEBACK_CTRL_REG_WB_THROTTLE_TIMEOUT_MASK << + CPU_WRITEBACK_CTRL_REG_WB_THROTTLE_TIMEOUT_SHIFT); + reg |= 8; + reg |= 7 << CPU_WRITEBACK_CTRL_REG_WB_THROTTLE_TIMEOUT_SHIFT; + cbc_writel(reg, CPU_WRITEBACK_CTRL_REG); +} + +static int __init setup_hifcpubiuctrl_regs(struct device_node *np) +{ + struct device_node *cpu_dn; + u32 family_id; + int ret = 0; + + cpubiuctrl_base = of_iomap(np, 0); + if (!cpubiuctrl_base) { + pr_err("failed to remap BIU control base\n"); + ret = -ENOMEM; + goto out; + } + + mcp_wr_pairing_en = of_property_read_bool(np, "brcm,write-pairing"); + + cpu_dn = of_get_cpu_node(0, NULL); + if (!cpu_dn) { + pr_err("failed to obtain CPU device node\n"); + ret = -ENODEV; + goto out; + } + + if (of_device_is_compatible(cpu_dn, "brcm,brahma-b15")) + cpubiuctrl_regs = b15_cpubiuctrl_regs; + else if (of_device_is_compatible(cpu_dn, "brcm,brahma-b53")) + cpubiuctrl_regs = b53_cpubiuctrl_regs; + else if (of_device_is_compatible(cpu_dn, "arm,cortex-a72")) + cpubiuctrl_regs = a72_cpubiuctrl_regs; + else { + pr_err("unsupported CPU\n"); + ret = -EINVAL; + } + of_node_put(cpu_dn); + + family_id = brcmstb_get_family_id(); + if (BRCM_ID(family_id) == 0x7260 && BRCM_REV(family_id) == 0) + cpubiuctrl_regs = b53_cpubiuctrl_no_wb_regs; +out: + of_node_put(np); + return ret; +} + +#ifdef CONFIG_PM_SLEEP +static u32 cpubiuctrl_reg_save[NUM_CPU_BIUCTRL_REGS]; + +static int brcmstb_cpu_credit_reg_suspend(void) +{ + unsigned int i; + + if (!cpubiuctrl_base) + return 0; + + for (i = 0; i < NUM_CPU_BIUCTRL_REGS; i++) + cpubiuctrl_reg_save[i] = cbc_readl(i); + + return 0; +} + +static void brcmstb_cpu_credit_reg_resume(void) +{ + unsigned int i; + + if (!cpubiuctrl_base) + return; + + for (i = 0; i < NUM_CPU_BIUCTRL_REGS; i++) + cbc_writel(cpubiuctrl_reg_save[i], i); +} + +static struct syscore_ops brcmstb_cpu_credit_syscore_ops = { + .suspend = brcmstb_cpu_credit_reg_suspend, + .resume = brcmstb_cpu_credit_reg_resume, +}; +#endif + + +static int __init brcmstb_biuctrl_init(void) +{ + struct device_node *np; + int ret; + + /* We might be running on a multi-platform kernel, don't make this a + * fatal error, just bail out early + */ + np = of_find_compatible_node(NULL, NULL, "brcm,brcmstb-cpu-biu-ctrl"); + if (!np) + return 0; + + ret = setup_hifcpubiuctrl_regs(np); + if (ret) + return ret; + + ret = mcp_write_pairing_set(); + if (ret) { + pr_err("MCP: Unable to disable write pairing!\n"); + return ret; + } + + a72_b53_rac_enable_all(np); + mcp_a72_b53_set(); +#ifdef CONFIG_PM_SLEEP + register_syscore_ops(&brcmstb_cpu_credit_syscore_ops); +#endif + return 0; +} +early_initcall(brcmstb_biuctrl_init); |