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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /drivers/soc/bcm/brcmstb/biuctrl.c
parentInitial commit. (diff)
downloadlinux-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.c356
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);