nds32: Remove the architecture

The nds32 architecture, also known as AndeStar V3, is a custom 32-bit
RISC target designed by Andes Technologies. Support was added to the
kernel in 2016 as the replacement RISC-V based V5 processors were
already announced, and maintained by (current or former) Andes
employees.

As explained by Alan Kao, new customers are now all using RISC-V,
and all known nds32 users are already on longterm stable kernels
provided by Andes, with no development work going into mainline
support any more.

While the port is still in a reasonably good shape, it only gets
worse over time without active maintainers, so it seems best
to remove it before it becomes unusable. As always, if it turns
out that there are mainline users after all, and they volunteer
to maintain the port in the future, the removal can be reverted.

Link: https://lore.kernel.org/linux-mm/YhdWNLUhk+x9RAzU@yamatobi.andestech.com/
Link: https://lore.kernel.org/lkml/20220302065213.82702-1-alankao@andestech.com/
Link: https://www.andestech.com/en/products-solutions/andestar-architecture/
Signed-off-by: Alan Kao <alankao@andestech.com>
[arnd: rewrite changelog to provide more background]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 0 insertions, 80 deletions

diff --git a/arch/nds32/kernel/pm.c b/arch/nds32/kernel/pm.c
deleted file mode 100644
index e25700e125d8..000000000000
--- a/arch/nds32/kernel/pm.c
+++ /dev/null
@@ -1,80 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-// Copyright (C) 2008-2017 Andes Technology Corporation
-
-#include <linux/init.h>
-#include <linux/suspend.h>
-#include <linux/device.h>
-#include <linux/printk.h>
-#include <asm/suspend.h>
-#include <nds32_intrinsic.h>
-
-unsigned int resume_addr;
-unsigned int *phy_addr_sp_tmp;
-
-static void nds32_suspend2ram(void)
-{
-	pgd_t *pgdv;
-	p4d_t *p4dv;
-	pud_t *pudv;
-	pmd_t *pmdv;
-	pte_t *ptev;
-
-	pgdv = (pgd_t *)__va((__nds32__mfsr(NDS32_SR_L1_PPTB) &
-		L1_PPTB_mskBASE)) + pgd_index((unsigned int)cpu_resume);
-
-	p4dv = p4d_offset(pgdv, (unsigned int)cpu_resume);
-	pudv = pud_offset(p4dv, (unsigned int)cpu_resume);
-	pmdv = pmd_offset(pudv, (unsigned int)cpu_resume);
-	ptev = pte_offset_map(pmdv, (unsigned int)cpu_resume);
-
-	resume_addr = ((*ptev) & TLB_DATA_mskPPN)
-			| ((unsigned int)cpu_resume & 0x00000fff);
-
-	suspend2ram();
-}
-
-static void nds32_suspend_cpu(void)
-{
-	while (!(__nds32__mfsr(NDS32_SR_INT_PEND) & wake_mask))
-		__asm__ volatile ("standby no_wake_grant\n\t");
-}
-
-static int nds32_pm_valid(suspend_state_t state)
-{
-	switch (state) {
-	case PM_SUSPEND_ON:
-	case PM_SUSPEND_STANDBY:
-	case PM_SUSPEND_MEM:
-		return 1;
-	default:
-		return 0;
-	}
-}
-
-static int nds32_pm_enter(suspend_state_t state)
-{
-	pr_debug("%s:state:%d\n", __func__, state);
-	switch (state) {
-	case PM_SUSPEND_STANDBY:
-		nds32_suspend_cpu();
-		return 0;
-	case PM_SUSPEND_MEM:
-		nds32_suspend2ram();
-		return 0;
-	default:
-		return -EINVAL;
-	}
-}
-
-static const struct platform_suspend_ops nds32_pm_ops = {
-	.valid = nds32_pm_valid,
-	.enter = nds32_pm_enter,
-};
-
-static int __init nds32_pm_init(void)
-{
-	pr_debug("Enter %s\n", __func__);
-	suspend_set_ops(&nds32_pm_ops);
-	return 0;
-}
-late_initcall(nds32_pm_init);