linux-kernel - [PATCH 20/22] ARM: sun8i: Add SMP support for the Allwinner A23

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 23 May 2014 15:51:23 +0800
From:	Chen-Yu Tsai <wens@...e.org>
To:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	Samuel Ortiz <sameo@...ux.intel.com>,
	Lee Jones <lee.jones@...aro.org>,
	Maxime Ripard <maxime.ripard@...e-electrons.com>,
	Rob Herring <robh+dt@...nel.org>,
	Mike Turquette <mturquette@...aro.org>,
	Emilio Lopez <emilio@...pez.com.ar>,
	Linus Walleij <linus.walleij@...aro.org>
Cc:	Chen-Yu Tsai <wens@...e.org>, linux-serial@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org, devicetree@...r.kernel.org,
	linux-kernel@...r.kernel.org, Hans de Goede <hdegoede@...hat.com>,
	Boris BREZILLON <boris.brezillon@...e-electrons.com>,
	Luc Verhaegen <libv@...net.be>
Subject: [PATCH 20/22] ARM: sun8i: Add SMP support for the Allwinner A23

The A23 is a dual Cortex-A7. Add the logic to use the IPs used to
control the CPU configuration and the CPU power so that we can
bring up secondary CPUs at boot.

Signed-off-by: Chen-Yu Tsai <wens@...e.org>
---
 arch/arm/mach-sunxi/platsmp.c | 69 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 69 insertions(+)

diff --git a/arch/arm/mach-sunxi/platsmp.c b/arch/arm/mach-sunxi/platsmp.c
index c53077b..688faaf 100644
--- a/arch/arm/mach-sunxi/platsmp.c
+++ b/arch/arm/mach-sunxi/platsmp.c
@@ -121,3 +121,72 @@ struct smp_operations sun6i_smp_ops __initdata = {
 	.smp_boot_secondary	= sun6i_smp_boot_secondary,
 };
 CPU_METHOD_OF_DECLARE(sun6i_smp, "allwinner,sun6i-a31", &sun6i_smp_ops);
+
+static void __init sun8i_smp_prepare_cpus(unsigned int max_cpus)
+{
+	struct device_node *node;
+
+	node = of_find_compatible_node(NULL, NULL, "allwinner,sun8i-a23-prcm");
+	if (!node) {
+		pr_err("Missing A23 PRCM node in the device tree\n");
+		return;
+	}
+
+	prcm_membase = of_iomap(node, 0);
+	if (!prcm_membase) {
+		pr_err("Couldn't map A23 PRCM registers\n");
+		return;
+	}
+
+	node = of_find_compatible_node(NULL, NULL,
+				       "allwinner,sun8i-a23-cpuconfig");
+	if (!node) {
+		pr_err("Missing A23 CPU config node in the device tree\n");
+		return;
+	}
+
+	cpucfg_membase = of_iomap(node, 0);
+	if (!cpucfg_membase)
+		pr_err("Couldn't map A23 CPU config registers\n");
+
+}
+
+static int sun8i_smp_boot_secondary(unsigned int cpu,
+				    struct task_struct *idle)
+{
+	u32 reg;
+
+	if (!(prcm_membase && cpucfg_membase))
+		return -EFAULT;
+
+	spin_lock(&cpu_lock);
+
+	/* Set CPU boot address */
+	writel(virt_to_phys(secondary_startup),
+	       cpucfg_membase + CPUCFG_PRIVATE0_REG);
+
+	/* Assert the CPU core in reset */
+	writel(0, cpucfg_membase + CPUCFG_CPU_RST_CTRL_REG(cpu));
+
+	/* Assert the L1 cache in reset */
+	reg = readl(cpucfg_membase + CPUCFG_GEN_CTRL_REG);
+	writel(reg & ~BIT(cpu), cpucfg_membase + CPUCFG_GEN_CTRL_REG);
+
+	/* Clear CPU power-off gating */
+	reg = readl(prcm_membase + PRCM_CPU_PWROFF_REG);
+	writel(reg & ~BIT(cpu), prcm_membase + PRCM_CPU_PWROFF_REG);
+	mdelay(1);
+
+	/* Deassert the CPU core reset */
+	writel(3, cpucfg_membase + CPUCFG_CPU_RST_CTRL_REG(cpu));
+
+	spin_unlock(&cpu_lock);
+
+	return 0;
+}
+
+struct smp_operations sun8i_smp_ops __initdata = {
+	.smp_prepare_cpus	= sun8i_smp_prepare_cpus,
+	.smp_boot_secondary	= sun8i_smp_boot_secondary,
+};
+CPU_METHOD_OF_DECLARE(sun8i_smp, "allwinner,sun8i-a23", &sun8i_smp_ops);
-- 
2.0.0.rc2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/