[PATCH] ARM: B15: Update to support Brahma-B53

From: Florian Fainelli
Date: Fri Feb 23 2018 - 15:41:24 EST


The B53 CPU design supports up to 8 processors, which moved the RAC_FLUSH_REG
offset 0x4 bytes below to make room for a RAC_CONFIG2_REG to control RAC
settings for CPU4-7.

Lookup the processor type (B15 or B53) and adjust the RAC_FLUSH_REG offset
accordingly, if we do not know the processor, bail out.

Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
---
arch/arm/mm/cache-b15-rac.c | 30 ++++++++++++++++++++++++++----
1 file changed, 26 insertions(+), 4 deletions(-)

diff --git a/arch/arm/mm/cache-b15-rac.c b/arch/arm/mm/cache-b15-rac.c
index d9586ba2e63c..c6ed14840c3c 100644
--- a/arch/arm/mm/cache-b15-rac.c
+++ b/arch/arm/mm/cache-b15-rac.c
@@ -33,7 +33,10 @@ extern void v7_flush_kern_cache_all(void);
#define RAC_CPU_SHIFT (8)
#define RACCFG_MASK (0xff)
#define RAC_CONFIG1_REG (0x7c)
-#define RAC_FLUSH_REG (0x80)
+/* Brahma-B15 is a quad-core only design */
+#define B15_RAC_FLUSH_REG (0x80)
+/* Brahma-B53 is an octo-core design */
+#define B53_RAC_FLUSH_REG (0x84)
#define FLUSH_RAC (1 << 0)

/* Bitmask to enable instruction and data prefetching with a 256-bytes stride */
@@ -52,6 +55,7 @@ static void __iomem *b15_rac_base;
static DEFINE_SPINLOCK(rac_lock);

static u32 rac_config0_reg;
+static u32 rac_flush_offset;

/* Initialization flag to avoid checking for b15_rac_base, and to prevent
* multi-platform kernels from crashing here as well.
@@ -70,14 +74,14 @@ static inline void __b15_rac_flush(void)
{
u32 reg;

- __raw_writel(FLUSH_RAC, b15_rac_base + RAC_FLUSH_REG);
+ __raw_writel(FLUSH_RAC, b15_rac_base + rac_flush_offset);
do {
/* This dmb() is required to force the Bus Interface Unit
* to clean oustanding writes, and forces an idle cycle
* to be inserted.
*/
dmb();
- reg = __raw_readl(b15_rac_base + RAC_FLUSH_REG);
+ reg = __raw_readl(b15_rac_base + rac_flush_offset);
} while (reg & FLUSH_RAC);
}

@@ -287,7 +291,7 @@ static struct syscore_ops b15_rac_syscore_ops = {

static int __init b15_rac_init(void)
{
- struct device_node *dn;
+ struct device_node *dn, *cpu_dn;
int ret = 0, cpu;
u32 reg, en_mask = 0;

@@ -305,6 +309,24 @@ static int __init b15_rac_init(void)
goto out;
}

+ cpu_dn = of_get_cpu_node(0, NULL);
+ if (!cpu_dn) {
+ ret = -ENODEV;
+ goto out;
+ }
+
+ if (of_device_is_compatible(cpu_dn, "brcm,brahma-b15"))
+ rac_flush_offset = B15_RAC_FLUSH_REG;
+ else if (of_device_is_compatible(cpu_dn, "brcm,brahma-b53"))
+ rac_flush_offset = B53_RAC_FLUSH_REG;
+ else {
+ pr_err("Unsupported CPU\n");
+ of_node_put(cpu_dn);
+ ret = -EINVAL;
+ goto out;
+ }
+ of_node_put(cpu_dn);
+
ret = register_reboot_notifier(&b15_rac_reboot_nb);
if (ret) {
pr_err("failed to register reboot notifier\n");
--
2.14.1