ARM: l2c: trial at enabling some Cortex-A9 optimisations

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

diff --git a/arch/arm/include/asm/hardware/cache-l2x0.h b/arch/arm/include/asm/hardware/cache-l2x0.h
index 84bbd31b89103d0b7de8ea9546919562c60591bf..3a5ec1c25659a0cd9a01763d98bfd7088d47bc50 100644 (file)
--- a/arch/arm/include/asm/hardware/cache-l2x0.h
+++ b/arch/arm/include/asm/hardware/cache-l2x0.h
@@ -134,6 +134,14 @@
 
 #define L310_ADDR_FILTER_EN            1
 
+#define L310_PREFETCH_CTRL_OFFSET_MASK         0x1f
+#define L310_PREFETCH_CTRL_DBL_LINEFILL_INCR   BIT(23)
+#define L310_PREFETCH_CTRL_PREFETCH_DROP       BIT(24)
+#define L310_PREFETCH_CTRL_DBL_LINEFILL_WRAP   BIT(27)
+#define L310_PREFETCH_CTRL_DATA_PREFETCH       BIT(28)
+#define L310_PREFETCH_CTRL_INSTR_PREFETCH      BIT(29)
+#define L310_PREFETCH_CTRL_DBL_LINEFILL                BIT(30)
+
 #define L2X0_CTRL_EN                   1
 
 #define L2X0_WAY_SIZE_SHIFT            3

diff --git a/arch/arm/mm/cache-l2x0.c b/arch/arm/mm/cache-l2x0.c
index e99a0ffd22d16854e7612595a70abb0819d4b146..efc5cabf70e082afed33c03f37cef0013a9e426a 100644 (file)
--- a/arch/arm/mm/cache-l2x0.c
+++ b/arch/arm/mm/cache-l2x0.c
@@ -16,14 +16,17 @@
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
+#include <linux/cpu.h>
 #include <linux/err.h>
 #include <linux/init.h>
+#include <linux/smp.h>
 #include <linux/spinlock.h>
 #include <linux/io.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
 
 #include <asm/cacheflush.h>
+#include <asm/cp15.h>
 #include <asm/cputype.h>
 #include <asm/hardware/cache-l2x0.h>
 #include "cache-tauros3.h"
@@ -639,7 +642,24 @@ static void l2c310_resume(void)
                                      L310_POWER_CTRL);
 
                l2c_enable(base, l2x0_saved_regs.aux_ctrl, 8);
+
+               /* Re-enable full-line-of-zeros for Cortex-A9 */
+               if (l2x0_saved_regs.aux_ctrl & L310_AUX_CTRL_FULL_LINE_ZERO)
+                       set_auxcr(get_auxcr() | BIT(3) | BIT(2) | BIT(1));
+       }
+}
+
+static int l2c310_cpu_enable_flz(struct notifier_block *nb, unsigned long act, void *data)
+{
+       switch (act & ~CPU_TASKS_FROZEN) {
+       case CPU_STARTING:
+               set_auxcr(get_auxcr() | BIT(3) | BIT(2) | BIT(1));
+               break;
+       case CPU_DYING:
+               set_auxcr(get_auxcr() & ~(BIT(3) | BIT(2) | BIT(1)));
+               break;
        }
+       return NOTIFY_OK;
 }
 
 static void __init l2c310_enable(void __iomem *base, u32 aux, unsigned num_lock)
@@ -657,6 +677,36 @@ static void __init l2c310_enable(void __iomem *base, u32 aux, unsigned num_lock)
                }
        }
 
+       if (cortex_a9) {
+               u32 aux_cur = readl_relaxed(base + L2X0_AUX_CTRL);
+               u32 acr = get_auxcr();
+
+               pr_debug("Cortex-A9 ACR=0x%08x\n", acr);
+
+               if (acr & BIT(3) && !(aux_cur & L310_AUX_CTRL_FULL_LINE_ZERO))
+                       pr_err("L2C-310: full line of zeros enabled in Cortex-A9 but not L2C-310 - invalid\n");
+
+               if (aux & L310_AUX_CTRL_FULL_LINE_ZERO && !(acr & BIT(3)))
+                       pr_err("L2C-310: enabling full line of zeros but not enabled in Cortex-A9\n");
+
+               if (!(aux & L310_AUX_CTRL_FULL_LINE_ZERO) && !outer_cache.write_sec) {
+                       aux |= L310_AUX_CTRL_FULL_LINE_ZERO;
+                       pr_info("L2C-310 full line of zeros enabled for Cortex-A9\n");
+               }
+       } else if (aux & (L310_AUX_CTRL_FULL_LINE_ZERO | L310_AUX_CTRL_EARLY_BRESP)) {
+               pr_err("L2C-310: disabling Cortex-A9 specific feature bits\n");
+               aux &= ~(L310_AUX_CTRL_FULL_LINE_ZERO | L310_AUX_CTRL_EARLY_BRESP);
+       }
+
+       if (aux & (L310_AUX_CTRL_DATA_PREFETCH | L310_AUX_CTRL_INSTR_PREFETCH)) {
+               u32 prefetch = readl_relaxed(base + L310_PREFETCH_CTRL);
+
+               pr_info("L2C-310 %s%s prefetch enabled, offset %u lines\n",
+                       aux & L310_AUX_CTRL_INSTR_PREFETCH ? "I" : "",
+                       aux & L310_AUX_CTRL_DATA_PREFETCH ? "D" : "",
+                       1 + (prefetch & L310_PREFETCH_CTRL_OFFSET_MASK));
+       }
+
        /* r3p0 or later has power control register */
        if (rev >= L310_CACHE_ID_RTL_R3P0) {
                u32 power_ctrl;
@@ -677,6 +727,11 @@ static void __init l2c310_enable(void __iomem *base, u32 aux, unsigned num_lock)
        aux |= L310_AUX_CTRL_NS_LOCKDOWN;
 
        l2c_enable(base, aux, num_lock);
+
+       if (aux & L310_AUX_CTRL_FULL_LINE_ZERO) {
+               set_auxcr(get_auxcr() | BIT(3) | BIT(2) | BIT(1));
+               cpu_notifier(l2c310_cpu_enable_flz, 0);
+       }
 }
 
 static void __init l2c310_fixup(void __iomem *base, u32 cache_id,
@@ -732,6 +787,18 @@ static void __init l2c310_fixup(void __iomem *base, u32 cache_id,
        }
 }
 
+static void l2c310_disable(void)
+{
+       /*
+        * If full-line-of-zeros is enabled, we must first disable it in the
+        * Cortex-A9 auxiliary control register before disabling the L2 cache.
+        */
+       if (l2x0_saved_regs.aux_ctrl & L310_AUX_CTRL_FULL_LINE_ZERO)
+               set_auxcr(get_auxcr() & ~(BIT(3) | BIT(2) | BIT(1)));
+
+       l2c_disable();
+}
+
 static const struct l2c_init_data l2c310_init_fns __initconst = {
        .type = "L2C-310",
        .way_size_0 = SZ_8K,
@@ -744,7 +811,7 @@ static const struct l2c_init_data l2c310_init_fns __initconst = {
                .clean_range = l2c210_clean_range,
                .flush_range = l2c210_flush_range,
                .flush_all = l2c210_flush_all,
-               .disable = l2c_disable,
+               .disable = l2c310_disable,
                .sync = l2c210_sync,
                .resume = l2c310_resume,
        },
@@ -995,7 +1062,7 @@ static const struct l2c_init_data of_l2c310_data __initconst = {
                .clean_range = l2c210_clean_range,
                .flush_range = l2c210_flush_range,
                .flush_all   = l2c210_flush_all,
-               .disable     = l2c_disable,
+               .disable     = l2c310_disable,
                .sync        = l2c210_sync,
                .resume      = l2c310_resume,
        },
@@ -1342,7 +1409,7 @@ static const struct l2c_init_data of_bcm_l2x0_data __initconst = {
                .clean_range = bcm_clean_range,
                .flush_range = bcm_flush_range,
                .flush_all   = l2c210_flush_all,
-               .disable     = l2c_disable,
+               .disable     = l2c310_disable,
                .sync        = l2c210_sync,
                .resume      = l2c310_resume,
        },