Merge tag 'arm-multiplatform-5.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc

Pull ARMv4T/v5 multiplatform support from Arnd Bergmann:
 "This series has been 12 years in the making, it mostly finishes the
  work that was started with the founding of Linaro to clean up platform
  support in the kernel.

  The largest change here is a cleanup of the omap1 platform, which is
  the final ARM machine type to get converted to the common-clk
  subsystem. All the omap1 specific drivers are now made independent of
  the mach/*.h headers to allow the platform to be part of a generic
  ARMv4/v5 multiplatform kernel.

  The last bit that enables this support is still missing here while we
  wait for some last dependencies to make it into the mainline kernel
  through other subsystems.

  The s3c24xx, ixp4xx, iop32x, ep93xx and dove platforms were all almost
  at the point of allowing multiplatform kernels, this work gets
  completed here along with a few additional cleanup. At the same time,
  the s3c24xx and s3c64xx are now deprecated and expected to get removed
  in the future.

  The PXA and OMAP1 bits are in a separate branch because of
  dependencies. Once both branches are merged, only the three Intel
  StrongARM platforms (RiscPC, Footbridge/NetWinder and StrongARM1100)
  need separate kernels, and there are no plans to include these"

* tag 'arm-multiplatform-5.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc: (61 commits)
  ARM: ixp4xx: Consolidate Kconfig fixing issue
  ARM: versatile: Add missing of_node_put in dcscb_init
  ARM: config: Refresh IXP4xx config after multiplatform
  ARM: omap1: add back omap_set_dma_priority() stub
  ARM: omap: fix missing declaration warnings
  ARM: omap: fix address space warnings from sparse
  ARM: spear: remove include/mach/ subdirectory
  ARM: davinci: remove include/mach/ subdirectory
  ARM: omap2: remove include/mach/ subdirectory
  integrator: remove empty ap_init_early()
  ARM: s3c: fix include path
  MAINTAINERS: omap1: Add Janusz as an additional maintainer
  ARM: omap1: htc_herald: fix typos in comments
  ARM: OMAP1: fix typos in comments
  ARM: OMAP1: clock: Remove noop code
  ARM: OMAP1: clock: Remove unused code
  ARM: OMAP1: clock: Fix UART rate reporting algorithm
  ARM: OMAP1: clock: Fix early UART rate issues
  ARM: OMAP1: Prepare for conversion of OMAP1 clocks to CCF
  ARM: omap1: fix build with no SoC selected
  ...

1 files changed, 261 insertions, 0 deletions

diff --git a/arch/arm/mach-versatile/tc2_pm.c b/arch/arm/mach-versatile/tc2_pm.c
new file mode 100644
index 000000000000..0fe78da0c109
--- /dev/null
+++ b/arch/arm/mach-versatile/tc2_pm.c
@@ -0,0 +1,261 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Created by:	Nicolas Pitre, October 2012
+ * Copyright:	(C) 2012-2013  Linaro Limited
+ *
+ * Some portions of this file were originally written by Achin Gupta
+ * Copyright:   (C) 2012  ARM Limited
+ */
+
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/errno.h>
+#include <linux/irqchip/arm-gic.h>
+
+#include <asm/mcpm.h>
+#include <asm/proc-fns.h>
+#include <asm/cacheflush.h>
+#include <asm/cputype.h>
+#include <asm/cp15.h>
+
+#include <linux/arm-cci.h>
+
+#include "spc.h"
+
+/* SCC conf registers */
+#define RESET_CTRL		0x018
+#define RESET_A15_NCORERESET(cpu)	(1 << (2 + (cpu)))
+#define RESET_A7_NCORERESET(cpu)	(1 << (16 + (cpu)))
+
+#define A15_CONF		0x400
+#define A7_CONF			0x500
+#define SYS_INFO		0x700
+#define SPC_BASE		0xb00
+
+static void __iomem *scc;
+
+#define TC2_CLUSTERS			2
+#define TC2_MAX_CPUS_PER_CLUSTER	3
+
+static unsigned int tc2_nr_cpus[TC2_CLUSTERS];
+
+static int tc2_pm_cpu_powerup(unsigned int cpu, unsigned int cluster)
+{
+	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
+	if (cluster >= TC2_CLUSTERS || cpu >= tc2_nr_cpus[cluster])
+		return -EINVAL;
+	ve_spc_set_resume_addr(cluster, cpu,
+			       __pa_symbol(mcpm_entry_point));
+	ve_spc_cpu_wakeup_irq(cluster, cpu, true);
+	return 0;
+}
+
+static int tc2_pm_cluster_powerup(unsigned int cluster)
+{
+	pr_debug("%s: cluster %u\n", __func__, cluster);
+	if (cluster >= TC2_CLUSTERS)
+		return -EINVAL;
+	ve_spc_powerdown(cluster, false);
+	return 0;
+}
+
+static void tc2_pm_cpu_powerdown_prepare(unsigned int cpu, unsigned int cluster)
+{
+	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
+	BUG_ON(cluster >= TC2_CLUSTERS || cpu >= TC2_MAX_CPUS_PER_CLUSTER);
+	ve_spc_cpu_wakeup_irq(cluster, cpu, true);
+	/*
+	 * If the CPU is committed to power down, make sure
+	 * the power controller will be in charge of waking it
+	 * up upon IRQ, ie IRQ lines are cut from GIC CPU IF
+	 * to the CPU by disabling the GIC CPU IF to prevent wfi
+	 * from completing execution behind power controller back
+	 */
+	gic_cpu_if_down(0);
+}
+
+static void tc2_pm_cluster_powerdown_prepare(unsigned int cluster)
+{
+	pr_debug("%s: cluster %u\n", __func__, cluster);
+	BUG_ON(cluster >= TC2_CLUSTERS);
+	ve_spc_powerdown(cluster, true);
+	ve_spc_global_wakeup_irq(true);
+}
+
+static void tc2_pm_cpu_cache_disable(void)
+{
+	v7_exit_coherency_flush(louis);
+}
+
+static void tc2_pm_cluster_cache_disable(void)
+{
+	if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A15) {
+		/*
+		 * On the Cortex-A15 we need to disable
+		 * L2 prefetching before flushing the cache.
+		 */
+		asm volatile(
+		"mcr	p15, 1, %0, c15, c0, 3 \n\t"
+		"isb	\n\t"
+		"dsb	"
+		: : "r" (0x400) );
+	}
+
+	v7_exit_coherency_flush(all);
+	cci_disable_port_by_cpu(read_cpuid_mpidr());
+}
+
+static int tc2_core_in_reset(unsigned int cpu, unsigned int cluster)
+{
+	u32 mask = cluster ?
+		  RESET_A7_NCORERESET(cpu)
+		: RESET_A15_NCORERESET(cpu);
+
+	return !(readl_relaxed(scc + RESET_CTRL) & mask);
+}
+
+#define POLL_MSEC 10
+#define TIMEOUT_MSEC 1000
+
+static int tc2_pm_wait_for_powerdown(unsigned int cpu, unsigned int cluster)
+{
+	unsigned tries;
+
+	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
+	BUG_ON(cluster >= TC2_CLUSTERS || cpu >= TC2_MAX_CPUS_PER_CLUSTER);
+
+	for (tries = 0; tries < TIMEOUT_MSEC / POLL_MSEC; ++tries) {
+		pr_debug("%s(cpu=%u, cluster=%u): RESET_CTRL = 0x%08X\n",
+			 __func__, cpu, cluster,
+			 readl_relaxed(scc + RESET_CTRL));
+
+		/*
+		 * We need the CPU to reach WFI, but the power
+		 * controller may put the cluster in reset and
+		 * power it off as soon as that happens, before
+		 * we have a chance to see STANDBYWFI.
+		 *
+		 * So we need to check for both conditions:
+		 */
+		if (tc2_core_in_reset(cpu, cluster) ||
+		    ve_spc_cpu_in_wfi(cpu, cluster))
+			return 0; /* success: the CPU is halted */
+
+		/* Otherwise, wait and retry: */
+		msleep(POLL_MSEC);
+	}
+
+	return -ETIMEDOUT; /* timeout */
+}
+
+static void tc2_pm_cpu_suspend_prepare(unsigned int cpu, unsigned int cluster)
+{
+	ve_spc_set_resume_addr(cluster, cpu, __pa_symbol(mcpm_entry_point));
+}
+
+static void tc2_pm_cpu_is_up(unsigned int cpu, unsigned int cluster)
+{
+	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
+	BUG_ON(cluster >= TC2_CLUSTERS || cpu >= TC2_MAX_CPUS_PER_CLUSTER);
+	ve_spc_cpu_wakeup_irq(cluster, cpu, false);
+	ve_spc_set_resume_addr(cluster, cpu, 0);
+}
+
+static void tc2_pm_cluster_is_up(unsigned int cluster)
+{
+	pr_debug("%s: cluster %u\n", __func__, cluster);
+	BUG_ON(cluster >= TC2_CLUSTERS);
+	ve_spc_powerdown(cluster, false);
+	ve_spc_global_wakeup_irq(false);
+}
+
+static const struct mcpm_platform_ops tc2_pm_power_ops = {
+	.cpu_powerup		= tc2_pm_cpu_powerup,
+	.cluster_powerup	= tc2_pm_cluster_powerup,
+	.cpu_suspend_prepare	= tc2_pm_cpu_suspend_prepare,
+	.cpu_powerdown_prepare	= tc2_pm_cpu_powerdown_prepare,
+	.cluster_powerdown_prepare = tc2_pm_cluster_powerdown_prepare,
+	.cpu_cache_disable	= tc2_pm_cpu_cache_disable,
+	.cluster_cache_disable	= tc2_pm_cluster_cache_disable,
+	.wait_for_powerdown	= tc2_pm_wait_for_powerdown,
+	.cpu_is_up		= tc2_pm_cpu_is_up,
+	.cluster_is_up		= tc2_pm_cluster_is_up,
+};
+
+/*
+ * Enable cluster-level coherency, in preparation for turning on the MMU.
+ */
+static void __naked tc2_pm_power_up_setup(unsigned int affinity_level)
+{
+	asm volatile (" \n"
+"	cmp	r0, #1 \n"
+"	bxne	lr \n"
+"	b	cci_enable_port_for_self ");
+}
+
+static int __init tc2_pm_init(void)
+{
+	unsigned int mpidr, cpu, cluster;
+	int ret, irq;
+	u32 a15_cluster_id, a7_cluster_id, sys_info;
+	struct device_node *np;
+
+	/*
+	 * The power management-related features are hidden behind
+	 * SCC registers. We need to extract runtime information like
+	 * cluster ids and number of CPUs really available in clusters.
+	 */
+	np = of_find_compatible_node(NULL, NULL,
+			"arm,vexpress-scc,v2p-ca15_a7");
+	scc = of_iomap(np, 0);
+	if (!scc)
+		return -ENODEV;
+
+	a15_cluster_id = readl_relaxed(scc + A15_CONF) & 0xf;
+	a7_cluster_id = readl_relaxed(scc + A7_CONF) & 0xf;
+	if (a15_cluster_id >= TC2_CLUSTERS || a7_cluster_id >= TC2_CLUSTERS)
+		return -EINVAL;
+
+	sys_info = readl_relaxed(scc + SYS_INFO);
+	tc2_nr_cpus[a15_cluster_id] = (sys_info >> 16) & 0xf;
+	tc2_nr_cpus[a7_cluster_id] = (sys_info >> 20) & 0xf;
+
+	irq = irq_of_parse_and_map(np, 0);
+
+	/*
+	 * A subset of the SCC registers is also used to communicate
+	 * with the SPC (power controller). We need to be able to
+	 * drive it very early in the boot process to power up
+	 * processors, so we initialize the SPC driver here.
+	 */
+	ret = ve_spc_init(scc + SPC_BASE, a15_cluster_id, irq);
+	if (ret)
+		return ret;
+
+	if (!cci_probed())
+		return -ENODEV;
+
+	mpidr = read_cpuid_mpidr();
+	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
+	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
+	if (cluster >= TC2_CLUSTERS || cpu >= tc2_nr_cpus[cluster]) {
+		pr_err("%s: boot CPU is out of bound!\n", __func__);
+		return -EINVAL;
+	}
+
+	ret = mcpm_platform_register(&tc2_pm_power_ops);
+	if (!ret) {
+		mcpm_sync_init(tc2_pm_power_up_setup);
+		/* test if we can (re)enable the CCI on our own */
+		BUG_ON(mcpm_loopback(tc2_pm_cluster_cache_disable) != 0);
+		pr_info("TC2 power management initialized\n");
+	}
+	return ret;
+}
+
+early_initcall(tc2_pm_init);