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[1/2] target/arm/tcg: increase cache level for cpu=max

Message ID 20240823125446.721-2-alireza.sanaee@huawei.com (mailing list archive)
State New, archived
Headers show
Series Specifying cache topology on ARM | expand

Commit Message

Alireza Sanaee Aug. 23, 2024, 12:54 p.m. UTC
This patch addresses cache description in the `aarch64_max_tcg_initfn`
function. It introduces three layers of caches and modifies the cache
description registers accordingly. Additionally, a new function is added
to handle cache description when CCIDX is disabled. The CCIDX remains
disabled for cpu=max configuration.

TODO: I am planning to send a separate patch using this cache
description function for the rest of the CPU types. This is a
starting point to test L3 caches for cpu=max.

Signed-off-by: Alireza Sanaee <alireza.sanaee@huawei.com>
---
 target/arm/tcg/cpu64.c | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)
diff mbox series

Patch

diff --git a/target/arm/tcg/cpu64.c b/target/arm/tcg/cpu64.c
index fe232eb306..f2b6fb6d84 100644
--- a/target/arm/tcg/cpu64.c
+++ b/target/arm/tcg/cpu64.c
@@ -55,6 +55,32 @@  static uint64_t make_ccsidr64(unsigned assoc, unsigned linesize,
          | (lg_linesize - 4);
 }
 
+static uint64_t make_ccsidr32(unsigned assoc, unsigned linesize,
+                              unsigned cachesize)
+{
+    unsigned lg_linesize = ctz32(linesize);
+    unsigned sets;
+
+    /*
+     * The 32-bit CCSIDR_EL1 format is:
+     *   [27:13] number of sets - 1
+     *   [12:3]  associativity - 1
+     *   [2:0]   log2(linesize) - 4
+     *           so 0 == 16 bytes, 1 == 32 bytes, 2 == 64 bytes, etc
+     */
+    assert(assoc != 0);
+    assert(is_power_of_2(linesize));
+    assert(lg_linesize >= 4 && lg_linesize <= 7 + 4);
+
+    /* sets * associativity * linesize == cachesize. */
+    sets = cachesize / (assoc * linesize);
+    assert(cachesize % (assoc * linesize) == 0);
+
+    return ((uint64_t)(sets - 1) << 13)
+         | ((assoc - 1) << 3)
+         | (lg_linesize - 4);
+}
+
 static void aarch64_a35_initfn(Object *obj)
 {
     ARMCPU *cpu = ARM_CPU(obj);
@@ -1086,6 +1112,15 @@  void aarch64_max_tcg_initfn(Object *obj)
     uint64_t t;
     uint32_t u;
 
+    /*
+     * Expanded cache set
+     */
+    cpu->clidr = 0x8200123; /* 4 4 3 in 3 bit fields */
+    cpu->ccsidr[0] = make_ccsidr32(4, 64, 64 * KiB); /* 64KB L1 dcache */
+    cpu->ccsidr[1] = cpu->ccsidr[0];                 /* 64KB L1 icache */
+    cpu->ccsidr[2] = make_ccsidr32(8, 64, 1 * MiB);  /* 1MB L2 unified cache */
+    cpu->ccsidr[4] = make_ccsidr32(8, 64, 2 * MiB);  /* 2MB L3 unified cache */
+
     /*
      * Unset ARM_FEATURE_BACKCOMPAT_CNTFRQ, which we would otherwise default
      * to because we started with aarch64_a57_initfn(). A 'max' CPU might