ARM: sun8i: smp: Add support for A83T

Add the support for A83T.

A83T SoC has an additional register than A80 to handle CPU configurations:
R_CPUS_CFG. Information about the register comes from Allwinner's BSP
driver.
An important difference is the Power Off Gating register for clusters
which is BIT(4) in case of SUN9I-A80 and BIT(0) in case of SUN8I-A83T.
There is also a bit swap between sun8i-a83t and sun9i-a80 that must be
handled.
Signed-off-by: Mylène Josserand <mylene.josserand@bootlin.com>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
Signed-off-by: Maxime Ripard <maxime.ripard@bootlin.com>

arch/arm/mach-sunxi/Kconfig

@@ -51,7 +51,7 @@ config MACH_SUN9I
 config ARCH_SUNXI_MC_SMP
 	bool
 	depends on SMP
-	default MACH_SUN9I
+	default MACH_SUN9I || MACH_SUN8I
 	select ARM_CCI400_PORT_CTRL
 	select ARM_CPU_SUSPEND
 

arch/arm/mach-sunxi/mc_smp.c

@@ -55,22 +55,31 @@
 #define CPUCFG_CX_RST_CTRL_L2_RST	BIT(8)
 #define CPUCFG_CX_RST_CTRL_CX_RST(n)	BIT(4 + (n))
 #define CPUCFG_CX_RST_CTRL_CORE_RST(n)	BIT(n)
+#define CPUCFG_CX_RST_CTRL_CORE_RST_ALL	(0xf << 0)
 
 #define PRCM_CPU_PO_RST_CTRL(c)		(0x4 + 0x4 * (c))
 #define PRCM_CPU_PO_RST_CTRL_CORE(n)	BIT(n)
 #define PRCM_CPU_PO_RST_CTRL_CORE_ALL	0xf
 #define PRCM_PWROFF_GATING_REG(c)	(0x100 + 0x4 * (c))
+/* The power off register for clusters are different from a80 and a83t */
+#define PRCM_PWROFF_GATING_REG_CLUSTER_SUN8I	BIT(0)
 #define PRCM_PWROFF_GATING_REG_CLUSTER_SUN9I	BIT(4)
 #define PRCM_PWROFF_GATING_REG_CORE(n)	BIT(n)
 #define PRCM_PWR_SWITCH_REG(c, cpu)	(0x140 + 0x10 * (c) + 0x4 * (cpu))
 #define PRCM_CPU_SOFT_ENTRY_REG		0x164
 
+/* R_CPUCFG registers, specific to sun8i-a83t */
+#define R_CPUCFG_CLUSTER_PO_RST_CTRL(c)	(0x30 + (c) * 0x4)
+#define R_CPUCFG_CLUSTER_PO_RST_CTRL_CORE(n)	BIT(n)
+#define R_CPUCFG_CPU_SOFT_ENTRY_REG		0x01a4
+
 #define CPU0_SUPPORT_HOTPLUG_MAGIC0	0xFA50392F
 #define CPU0_SUPPORT_HOTPLUG_MAGIC1	0x790DCA3A
 
 static void __iomem *cpucfg_base;
 static void __iomem *prcm_base;
 static void __iomem *sram_b_smp_base;
+static void __iomem *r_cpucfg_base;
 
 extern void sunxi_mc_smp_secondary_startup(void);
 extern void sunxi_mc_smp_resume(void);
@@ -161,6 +170,16 @@ static int sunxi_cpu_powerup(unsigned int cpu, unsigned int cluster)
 	reg &= ~PRCM_CPU_PO_RST_CTRL_CORE(cpu);
 	writel(reg, prcm_base + PRCM_CPU_PO_RST_CTRL(cluster));
 
+	if (is_a83t) {
+		/* assert cpu power-on reset */
+		reg  = readl(r_cpucfg_base +
+			     R_CPUCFG_CLUSTER_PO_RST_CTRL(cluster));
+		reg &= ~(R_CPUCFG_CLUSTER_PO_RST_CTRL_CORE(cpu));
+		writel(reg, r_cpucfg_base +
+		       R_CPUCFG_CLUSTER_PO_RST_CTRL(cluster));
+		udelay(10);
+	}
+
 	/* Cortex-A7: hold L1 reset disable signal low */
 	if (!sunxi_core_is_cortex_a15(cpu, cluster)) {
 		reg = readl(cpucfg_base + CPUCFG_CX_CTRL_REG0(cluster));
@@ -184,17 +203,38 @@ static int sunxi_cpu_powerup(unsigned int cpu, unsigned int cluster)
 	/* open power switch */
 	sunxi_cpu_power_switch_set(cpu, cluster, true);
 
+	/* Handle A83T bit swap */
+	if (is_a83t) {
+		if (cpu == 0)
+			cpu = 4;
+	}
+
 	/* clear processor power gate */
 	reg = readl(prcm_base + PRCM_PWROFF_GATING_REG(cluster));
 	reg &= ~PRCM_PWROFF_GATING_REG_CORE(cpu);
 	writel(reg, prcm_base + PRCM_PWROFF_GATING_REG(cluster));
 	udelay(20);
 
+	/* Handle A83T bit swap */
+	if (is_a83t) {
+		if (cpu == 4)
+			cpu = 0;
+	}
+
 	/* de-assert processor power-on reset */
 	reg = readl(prcm_base + PRCM_CPU_PO_RST_CTRL(cluster));
 	reg |= PRCM_CPU_PO_RST_CTRL_CORE(cpu);
 	writel(reg, prcm_base + PRCM_CPU_PO_RST_CTRL(cluster));
 
+	if (is_a83t) {
+		reg  = readl(r_cpucfg_base +
+			     R_CPUCFG_CLUSTER_PO_RST_CTRL(cluster));
+		reg |= R_CPUCFG_CLUSTER_PO_RST_CTRL_CORE(cpu);
+		writel(reg, r_cpucfg_base +
+		       R_CPUCFG_CLUSTER_PO_RST_CTRL(cluster));
+		udelay(10);
+	}
+
 	/* de-assert all processor resets */
 	reg = readl(cpucfg_base + CPUCFG_CX_RST_CTRL(cluster));
 	reg |= CPUCFG_CX_RST_CTRL_DBG_RST(cpu);
@@ -216,6 +256,14 @@ static int sunxi_cluster_powerup(unsigned int cluster)
 	if (cluster >= SUNXI_NR_CLUSTERS)
 		return -EINVAL;
 
+	/* For A83T, assert cluster cores resets */
+	if (is_a83t) {
+		reg = readl(cpucfg_base + CPUCFG_CX_RST_CTRL(cluster));
+		reg &= ~CPUCFG_CX_RST_CTRL_CORE_RST_ALL;   /* Core Reset    */
+		writel(reg, cpucfg_base + CPUCFG_CX_RST_CTRL(cluster));
+		udelay(10);
+	}
+
 	/* assert ACINACTM */
 	reg = readl(cpucfg_base + CPUCFG_CX_CTRL_REG1(cluster));
 	reg |= CPUCFG_CX_CTRL_REG1_ACINACTM;
@@ -226,6 +274,16 @@ static int sunxi_cluster_powerup(unsigned int cluster)
 	reg &= ~PRCM_CPU_PO_RST_CTRL_CORE_ALL;
 	writel(reg, prcm_base + PRCM_CPU_PO_RST_CTRL(cluster));
 
+	/* assert cluster cores resets */
+	if (is_a83t) {
+		reg  = readl(r_cpucfg_base +
+			     R_CPUCFG_CLUSTER_PO_RST_CTRL(cluster));
+		reg &= ~CPUCFG_CX_RST_CTRL_CORE_RST_ALL;
+		writel(reg, r_cpucfg_base +
+		       R_CPUCFG_CLUSTER_PO_RST_CTRL(cluster));
+		udelay(10);
+	}
+
 	/* assert cluster resets */
 	reg = readl(cpucfg_base + CPUCFG_CX_RST_CTRL(cluster));
 	reg &= ~CPUCFG_CX_RST_CTRL_DBG_SOC_RST;
@@ -256,6 +314,9 @@ static int sunxi_cluster_powerup(unsigned int cluster)
 
 	/* clear cluster power gate */
 	reg = readl(prcm_base + PRCM_PWROFF_GATING_REG(cluster));
+	if (is_a83t)
+		reg &= ~PRCM_PWROFF_GATING_REG_CLUSTER_SUN8I;
+	else
 		reg &= ~PRCM_PWROFF_GATING_REG_CLUSTER_SUN9I;
 	writel(reg, prcm_base + PRCM_PWROFF_GATING_REG(cluster));
 	udelay(20);
@@ -453,6 +514,9 @@ static int sunxi_cluster_powerdown(unsigned int cluster)
 	/* gate cluster power */
 	pr_debug("%s: gate cluster power\n", __func__);
 	reg = readl(prcm_base + PRCM_PWROFF_GATING_REG(cluster));
+	if (is_a83t)
+		reg |= PRCM_PWROFF_GATING_REG_CLUSTER_SUN8I;
+	else
 		reg |= PRCM_PWROFF_GATING_REG_CLUSTER_SUN9I;
 	writel(reg, prcm_base + PRCM_PWROFF_GATING_REG(cluster));
 	udelay(20);
@@ -535,8 +599,12 @@ static int sunxi_mc_smp_cpu_kill(unsigned int l_cpu)
 	return !ret;
 }
 
-static bool sunxi_mc_smp_cpu_can_disable(unsigned int __unused)
+static bool sunxi_mc_smp_cpu_can_disable(unsigned int cpu)
 {
+	/* CPU0 hotplug not handled for sun8i-a83t */
+	if (is_a83t)
+		if (cpu == 0)
+			return false;
 	return true;
 }
 #endif
@@ -619,6 +687,7 @@ struct sunxi_mc_smp_nodes {
 	struct device_node *prcm_node;
 	struct device_node *cpucfg_node;
 	struct device_node *sram_node;
+	struct device_node *r_cpucfg_node;
 };
 
 /* This structure holds SoC-specific bits tied to an enable-method string. */
@@ -633,6 +702,7 @@ static void __init sunxi_mc_smp_put_nodes(struct sunxi_mc_smp_nodes *nodes)
 	of_node_put(nodes->prcm_node);
 	of_node_put(nodes->cpucfg_node);
 	of_node_put(nodes->sram_node);
+	of_node_put(nodes->r_cpucfg_node);
 	memset(nodes, 0, sizeof(*nodes));
 }
 
@@ -662,11 +732,42 @@ static int __init sun9i_a80_get_smp_nodes(struct sunxi_mc_smp_nodes *nodes)
 	return 0;
 }
 
+static int __init sun8i_a83t_get_smp_nodes(struct sunxi_mc_smp_nodes *nodes)
+{
+	nodes->prcm_node = of_find_compatible_node(NULL, NULL,
+						   "allwinner,sun8i-a83t-r-ccu");
+	if (!nodes->prcm_node) {
+		pr_err("%s: PRCM not available\n", __func__);
+		return -ENODEV;
+	}
+
+	nodes->cpucfg_node = of_find_compatible_node(NULL, NULL,
+						     "allwinner,sun8i-a83t-cpucfg");
+	if (!nodes->cpucfg_node) {
+		pr_err("%s: CPUCFG not available\n", __func__);
+		return -ENODEV;
+	}
+
+	nodes->r_cpucfg_node = of_find_compatible_node(NULL, NULL,
+						       "allwinner,sun8i-a83t-r-cpucfg");
+	if (!nodes->r_cpucfg_node) {
+		pr_err("%s: RCPUCFG not available\n", __func__);
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
 static const struct sunxi_mc_smp_data sunxi_mc_smp_data[] __initconst = {
 	{
 		.enable_method	= "allwinner,sun9i-a80-smp",
 		.get_smp_nodes	= sun9i_a80_get_smp_nodes,
 	},
+	{
+		.enable_method	= "allwinner,sun8i-a83t-smp",
+		.get_smp_nodes	= sun8i_a83t_get_smp_nodes,
+		.is_a83t	= true,
+	},
 };
 
 static int __init sunxi_mc_smp_init(void)
@@ -674,6 +775,7 @@ static int __init sunxi_mc_smp_init(void)
 	struct sunxi_mc_smp_nodes nodes = { 0 };
 	struct device_node *node;
 	struct resource res;
+	void __iomem *addr;
 	int i, ret;
 
 	/*
@@ -738,6 +840,16 @@ static int __init sunxi_mc_smp_init(void)
 		goto err_unmap_prcm;
 	}
 
+	if (is_a83t) {
+		r_cpucfg_base = of_io_request_and_map(nodes.r_cpucfg_node,
+						      0, "sunxi-mc-smp");
+		if (IS_ERR(r_cpucfg_base)) {
+			ret = PTR_ERR(r_cpucfg_base);
+			pr_err("%s: failed to map R-CPUCFG registers\n",
+			       __func__);
+			goto err_unmap_release_cpucfg;
+		}
+	} else {
 		sram_b_smp_base = of_io_request_and_map(nodes.sram_node, 0,
 							"sunxi-mc-smp");
 		if (IS_ERR(sram_b_smp_base)) {
@@ -745,21 +857,25 @@ static int __init sunxi_mc_smp_init(void)
 			pr_err("%s: failed to map secure SRAM\n", __func__);
 			goto err_unmap_release_cpucfg;
 		}
+	}
 
 	/* Configure CCI-400 for boot cluster */
 	ret = sunxi_mc_smp_loopback();
 	if (ret) {
 		pr_err("%s: failed to configure boot cluster: %d\n",
 		       __func__, ret);
-		goto err_unmap_release_secure_sram;
+		goto err_unmap_release_sram_rcpucfg;
 	}
 
 	/* We don't need the device nodes anymore */
 	sunxi_mc_smp_put_nodes(&nodes);
 
 	/* Set the hardware entry point address */
-	writel(__pa_symbol(sunxi_mc_smp_secondary_startup),
-	       prcm_base + PRCM_CPU_SOFT_ENTRY_REG);
+	if (is_a83t)
+		addr = r_cpucfg_base + R_CPUCFG_CPU_SOFT_ENTRY_REG;
+	else
+		addr = prcm_base + PRCM_CPU_SOFT_ENTRY_REG;
+	writel(__pa_symbol(sunxi_mc_smp_secondary_startup), addr);
 
 	/* Actually enable multi cluster SMP */
 	smp_set_ops(&sunxi_mc_smp_smp_ops);
@@ -768,9 +884,14 @@ static int __init sunxi_mc_smp_init(void)
 
 	return 0;
 
-err_unmap_release_secure_sram:
+err_unmap_release_sram_rcpucfg:
+	if (is_a83t) {
+		iounmap(r_cpucfg_base);
+		of_address_to_resource(nodes.r_cpucfg_node, 0, &res);
+	} else {
 		iounmap(sram_b_smp_base);
 		of_address_to_resource(nodes.sram_node, 0, &res);
+	}
 	release_mem_region(res.start, resource_size(&res));
 err_unmap_release_cpucfg:
 	iounmap(cpucfg_base);