From: David Gibson <david@gibson.dropbear.id.au>
To: qemu-devel@nongnu.org, groug@kaod.org, philmd@redhat.com, clg@kaod.org
Cc: lvivier@redhat.com, aik@ozlabs.ru,
Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>,
qemu-ppc@nongnu.org, paulus@samba.org,
David Gibson <david@gibson.dropbear.id.au>
Subject: [PATCH v2 08/10] target/ppc: Streamline calculation of RMA limit from LPCR[RMLS]
Date: Tue, 7 Jan 2020 15:48:25 +1100 [thread overview]
Message-ID: <20200107044827.471355-9-david@gibson.dropbear.id.au> (raw)
In-Reply-To: <20200107044827.471355-1-david@gibson.dropbear.id.au>
Currently we use a big switch statement in ppc_hash64_update_rmls() to work
out what the right RMA limit is based on the LPCR[RMLS] field. There's no
formula for this - it's just an arbitrary mapping defined by the existing
CPU implementations - but we can make it a bit more readable by using a
lookup table rather than a switch. In addition we can use the MiB/GiB
symbols to make it a bit clearer.
While there we add a bit of clarity and rationale to the comment about
what happens if the LPCR[RMLS] doesn't contain a valid value.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
target/ppc/mmu-hash64.c | 71 ++++++++++++++++++++---------------------
1 file changed, 35 insertions(+), 36 deletions(-)
diff --git a/target/ppc/mmu-hash64.c b/target/ppc/mmu-hash64.c
index 127b7250ae..bb9ebeaf48 100644
--- a/target/ppc/mmu-hash64.c
+++ b/target/ppc/mmu-hash64.c
@@ -18,6 +18,7 @@
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "qemu/osdep.h"
+#include "qemu/units.h"
#include "cpu.h"
#include "exec/exec-all.h"
#include "exec/helper-proto.h"
@@ -755,6 +756,39 @@ static void ppc_hash64_set_c(PowerPCCPU *cpu, hwaddr ptex, uint64_t pte1)
stb_phys(CPU(cpu)->as, base + offset, (pte1 & 0xff) | 0x80);
}
+static target_ulong rmls_limit(PowerPCCPU *cpu)
+{
+ CPUPPCState *env = &cpu->env;
+ /*
+ * This is the full 4 bits encoding of POWER8. Previous
+ * CPUs only support a subset of these but the filtering
+ * is done when writing LPCR
+ */
+ const target_ulong rma_sizes[] = {
+ [0] = 0,
+ [1] = 16 * GiB,
+ [2] = 1 * GiB,
+ [3] = 64 * MiB,
+ [4] = 256 * MiB,
+ [5] = 0,
+ [6] = 0,
+ [7] = 128 * MiB,
+ [8] = 32 * MiB,
+ };
+ target_ulong rmls = (env->spr[SPR_LPCR] & LPCR_RMLS) >> LPCR_RMLS_SHIFT;
+
+ if (rmls < ARRAY_SIZE(rma_sizes)) {
+ return rma_sizes[rmls];
+ } else {
+ /*
+ * Bad value, so the OS has shot itself in the foot. Return a
+ * 0-sized RMA which we expect to trigger an immediate DSI or
+ * ISI
+ */
+ return 0;
+ }
+}
+
int ppc_hash64_handle_mmu_fault(PowerPCCPU *cpu, vaddr eaddr,
int rwx, int mmu_idx)
{
@@ -1004,41 +1038,6 @@ void ppc_hash64_tlb_flush_hpte(PowerPCCPU *cpu, target_ulong ptex,
cpu->env.tlb_need_flush = TLB_NEED_GLOBAL_FLUSH | TLB_NEED_LOCAL_FLUSH;
}
-static void ppc_hash64_update_rmls(PowerPCCPU *cpu)
-{
- CPUPPCState *env = &cpu->env;
- uint64_t lpcr = env->spr[SPR_LPCR];
-
- /*
- * This is the full 4 bits encoding of POWER8. Previous
- * CPUs only support a subset of these but the filtering
- * is done when writing LPCR
- */
- switch ((lpcr & LPCR_RMLS) >> LPCR_RMLS_SHIFT) {
- case 0x8: /* 32MB */
- env->rmls = 0x2000000ull;
- break;
- case 0x3: /* 64MB */
- env->rmls = 0x4000000ull;
- break;
- case 0x7: /* 128MB */
- env->rmls = 0x8000000ull;
- break;
- case 0x4: /* 256MB */
- env->rmls = 0x10000000ull;
- break;
- case 0x2: /* 1GB */
- env->rmls = 0x40000000ull;
- break;
- case 0x1: /* 16GB */
- env->rmls = 0x400000000ull;
- break;
- default:
- /* What to do here ??? */
- env->rmls = 0;
- }
-}
-
static void ppc_hash64_update_vrma(PowerPCCPU *cpu)
{
CPUPPCState *env = &cpu->env;
@@ -1097,7 +1096,7 @@ void ppc_store_lpcr(PowerPCCPU *cpu, target_ulong val)
CPUPPCState *env = &cpu->env;
env->spr[SPR_LPCR] = val & pcc->lpcr_mask;
- ppc_hash64_update_rmls(cpu);
+ env->rmls = rmls_limit(cpu);
ppc_hash64_update_vrma(cpu);
}
--
2.24.1
next prev parent reply other threads:[~2020-01-07 5:07 UTC|newest]
Thread overview: 38+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-07 4:48 [PATCH v2 00/10] target/ppc: Correct some errors with real mode handling David Gibson
2020-01-07 4:48 ` [PATCH v2 01/10] ppc: Drop PPC_EMULATE_32BITS_HYPV stub David Gibson
2020-01-07 12:52 ` Cédric Le Goater
2020-01-07 17:05 ` Greg Kurz
2020-01-07 4:48 ` [PATCH v2 02/10] ppc: Remove stub of PPC970 HID4 implementation David Gibson
2020-01-07 12:51 ` Cédric Le Goater
2020-01-07 17:32 ` Greg Kurz
2020-01-07 17:36 ` Greg Kurz
2020-01-07 18:05 ` BALATON Zoltan
2020-01-08 1:09 ` David Gibson
2020-01-08 8:29 ` Thomas Huth
2020-01-08 1:08 ` David Gibson
2020-01-08 8:11 ` Greg Kurz
2020-01-08 2:17 ` Paul Mackerras
2020-01-08 13:35 ` Greg Kurz
2020-01-07 4:48 ` [PATCH v2 03/10] target/ppc: Correct handling of real mode accesses with vhyp on hash MMU David Gibson
2020-01-14 10:22 ` Cédric Le Goater
2020-01-07 4:48 ` [PATCH v2 04/10] target/ppc: Introduce ppc_hash64_use_vrma() helper David Gibson
2020-01-07 13:24 ` Cédric Le Goater
2020-01-07 4:48 ` [PATCH v2 05/10] spapr, ppc: Remove VPM0/RMLS hacks for POWER9 David Gibson
2020-01-07 14:35 ` Cédric Le Goater
2020-01-09 7:33 ` Alexey Kardashevskiy
2020-01-13 3:38 ` David Gibson
2020-01-07 4:48 ` [PATCH v2 06/10] target/ppc: Remove RMOR register from POWER9 & POWER10 David Gibson
2020-01-07 13:39 ` Cédric Le Goater
2020-01-07 4:48 ` [PATCH v2 07/10] target/ppc: Use class fields to simplify LPCR masking David Gibson
2020-01-07 13:41 ` Cédric Le Goater
2020-01-07 4:48 ` David Gibson [this message]
2020-01-07 13:43 ` [PATCH v2 08/10] target/ppc: Streamline calculation of RMA limit from LPCR[RMLS] Cédric Le Goater
2020-01-07 4:48 ` [PATCH v2 09/10] target/ppc: Correct RMLS table David Gibson
2020-01-07 14:21 ` Cédric Le Goater
2020-01-08 1:06 ` David Gibson
2020-01-08 8:29 ` Cédric Le Goater
2020-01-09 7:46 ` Alexey Kardashevskiy
2020-01-13 3:46 ` David Gibson
2020-01-08 8:28 ` Cédric Le Goater
2020-01-07 4:48 ` [PATCH v2 10/10] target/ppc: Only calculate RMLS derived RMA limit on demand David Gibson
2020-01-08 8:31 ` Cédric Le Goater
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