xref: /openbmc/linux/arch/arm/mm/l2c-l2x0-resume.S (revision 3cf3cdea)
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * L2C-310 early resume code.  This can be used by platforms to restore
4 * the settings of their L2 cache controller before restoring the
5 * processor state.
6 *
7 * This code can only be used to if you are running in the secure world.
8 */
9#include <linux/linkage.h>
10#include <asm/assembler.h>
11#include <asm/hardware/cache-l2x0.h>
12
13	.text
14
15ENTRY(l2c310_early_resume)
16	adr	r0, 1f
17	ldr	r2, [r0]
18	add	r0, r2, r0
19
20	ldmia	r0, {r1, r2, r3, r4, r5, r6, r7, r8}
21	@ r1 = phys address of L2C-310 controller
22	@ r2 = aux_ctrl
23	@ r3 = tag_latency
24	@ r4 = data_latency
25	@ r5 = filter_start
26	@ r6 = filter_end
27	@ r7 = prefetch_ctrl
28	@ r8 = pwr_ctrl
29
30	@ Check that the address has been initialised
31	teq	r1, #0
32	reteq	lr
33
34	@ The prefetch and power control registers are revision dependent
35	@ and can be written whether or not the L2 cache is enabled
36	ldr	r0, [r1, #L2X0_CACHE_ID]
37	and	r0, r0, #L2X0_CACHE_ID_RTL_MASK
38	cmp	r0, #L310_CACHE_ID_RTL_R2P0
39	strcs	r7, [r1, #L310_PREFETCH_CTRL]
40	cmp	r0, #L310_CACHE_ID_RTL_R3P0
41	strcs	r8, [r1, #L310_POWER_CTRL]
42
43	@ Don't setup the L2 cache if it is already enabled
44	ldr	r0, [r1, #L2X0_CTRL]
45	tst	r0, #L2X0_CTRL_EN
46	retne	lr
47
48	str	r3, [r1, #L310_TAG_LATENCY_CTRL]
49	str	r4, [r1, #L310_DATA_LATENCY_CTRL]
50	str	r6, [r1, #L310_ADDR_FILTER_END]
51	str	r5, [r1, #L310_ADDR_FILTER_START]
52
53	str	r2, [r1, #L2X0_AUX_CTRL]
54	mov	r9, #L2X0_CTRL_EN
55	str	r9, [r1, #L2X0_CTRL]
56	ret	lr
57ENDPROC(l2c310_early_resume)
58
59	.align
601:	.long	l2x0_saved_regs - .
61