RISC-V: Remove CLINT related code from timer and arch

Right now the RISC-V timer driver is convoluted to support:
1. Linux RISC-V S-mode (with MMU) where it will use TIME CSR for
   clocksource and SBI timer calls for clockevent device.
2. Linux RISC-V M-mode (without MMU) where it will use CLINT MMIO
   counter register for clocksource and CLINT MMIO compare register
   for clockevent device.

We now have a separate CLINT timer driver which also provide CLINT
based IPI operations so let's remove CLINT MMIO related code from
arch/riscv directory and RISC-V timer driver.

Signed-off-by: Anup Patel <anup.patel@wdc.com>
Tested-by: Emil Renner Berhing <kernel@esmil.dk>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>

5 files changed, 1 insertions, 68 deletions

diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile
index a5287ab9f7f2..dc93710f0b2f 100644
--- a/arch/riscv/kernel/Makefile
+++ b/arch/riscv/kernel/Makefile
@@ -31,7 +31,7 @@ obj-y	+= cacheinfo.o
 obj-y	+= patch.o
 obj-$(CONFIG_MMU) += vdso.o vdso/
 
-obj-$(CONFIG_RISCV_M_MODE)	+= clint.o traps_misaligned.o
+obj-$(CONFIG_RISCV_M_MODE)	+= traps_misaligned.o
 obj-$(CONFIG_FPU)		+= fpu.o
 obj-$(CONFIG_SMP)		+= smpboot.o
 obj-$(CONFIG_SMP)		+= smp.o
diff --git a/arch/riscv/kernel/clint.c b/arch/riscv/kernel/clint.c
deleted file mode 100644
index a9845ee023e2..000000000000
--- a/arch/riscv/kernel/clint.c
+++ /dev/null
@@ -1,63 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright (c) 2019 Christoph Hellwig.
- */
-
-#include <linux/io.h>
-#include <linux/of_address.h>
-#include <linux/smp.h>
-#include <linux/types.h>
-#include <asm/clint.h>
-#include <asm/csr.h>
-#include <asm/timex.h>
-
-/*
- * This is the layout used by the SiFive clint, which is also shared by the qemu
- * virt platform, and the Kendryte KD210 at least.
- */
-#define CLINT_IPI_OFF		0
-#define CLINT_TIME_CMP_OFF	0x4000
-#define CLINT_TIME_VAL_OFF	0xbff8
-
-u32 __iomem *clint_ipi_base;
-
-static void clint_send_ipi(const struct cpumask *target)
-{
-	unsigned int cpu;
-
-	for_each_cpu(cpu, target)
-		writel(1, clint_ipi_base + cpuid_to_hartid_map(cpu));
-}
-
-static void clint_clear_ipi(void)
-{
-	writel(0, clint_ipi_base + cpuid_to_hartid_map(smp_processor_id()));
-}
-
-static struct riscv_ipi_ops clint_ipi_ops = {
-	.ipi_inject = clint_send_ipi,
-	.ipi_clear = clint_clear_ipi,
-};
-
-void clint_init_boot_cpu(void)
-{
-	struct device_node *np;
-	void __iomem *base;
-
-	np = of_find_compatible_node(NULL, NULL, "riscv,clint0");
-	if (!np) {
-		panic("clint not found");
-		return;
-	}
-
-	base = of_iomap(np, 0);
-	if (!base)
-		panic("could not map CLINT");
-
-	clint_ipi_base = base + CLINT_IPI_OFF;
-	riscv_time_cmp = base + CLINT_TIME_CMP_OFF;
-	riscv_time_val = base + CLINT_TIME_VAL_OFF;
-
-	clint_clear_ipi();
-	riscv_set_ipi_ops(&clint_ipi_ops);
-}
diff --git a/arch/riscv/kernel/setup.c b/arch/riscv/kernel/setup.c
index f04373be54a6..2c6dd329312b 100644
--- a/arch/riscv/kernel/setup.c
+++ b/arch/riscv/kernel/setup.c
@@ -18,7 +18,6 @@
 #include <linux/swiotlb.h>
 #include <linux/smp.h>
 
-#include <asm/clint.h>
 #include <asm/cpu_ops.h>
 #include <asm/setup.h>
 #include <asm/sections.h>
@@ -79,7 +78,6 @@ void __init setup_arch(char **cmdline_p)
 #else
 	unflatten_device_tree();
 #endif
-	clint_init_boot_cpu();
 
 #ifdef CONFIG_SWIOTLB
 	swiotlb_init(1);
diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
index cf9acb43604c..ea028d9e0d24 100644
--- a/arch/riscv/kernel/smp.c
+++ b/arch/riscv/kernel/smp.c
@@ -18,7 +18,6 @@
 #include <linux/delay.h>
 #include <linux/irq_work.h>
 
-#include <asm/clint.h>
 #include <asm/sbi.h>
 #include <asm/tlbflush.h>
 #include <asm/cacheflush.h>
diff --git a/arch/riscv/kernel/smpboot.c b/arch/riscv/kernel/smpboot.c
index 12033d71ba0c..96167d55ed98 100644
--- a/arch/riscv/kernel/smpboot.c
+++ b/arch/riscv/kernel/smpboot.c
@@ -24,7 +24,6 @@
 #include <linux/of.h>
 #include <linux/sched/task_stack.h>
 #include <linux/sched/mm.h>
-#include <asm/clint.h>
 #include <asm/cpu_ops.h>
 #include <asm/irq.h>
 #include <asm/mmu_context.h>