The cmd "cpu detail" fetches uninitialized cpu feature information
and thus displays wrong / inconsitent details as below. FU540-C000 doesn't
have any microcode, yet the cmd display's it.
=> cpu detail
0: cpu@0 rv64imac
ID = 0, freq = 999.100 MHz: L1 cache, MMU, Microcode, Device ID
Microcode version 0x0
Device ID 0x0
1: cpu@1 rv64imafdc
ID = 1, freq = 999.100 MHz: L1 cache, MMU, Microcode, Device ID
Microcode version 0x0
Device ID 0x0
2: cpu@2 rv64imafdc
ID = 2, freq = 999.100 MHz: L1 cache, MMU, Microcode, Device ID
Microcode version 0x0
Device ID 0x0
3: cpu@3 rv64imafdc
ID = 3, freq = 999.100 MHz: L1 cache, MMU, Microcode, Device ID
Microcode version 0x0
Device ID 0x0
4: cpu@4 rv64imafdc
ID = 4, freq = 999.100 MHz: L1 cache, MMU, Microcode, Device ID
Microcode version 0x0
Device ID 0x0
The L1 cache or MMU entry seen above is also displayed inconsistently.
So initialize features to zero before fetching from device tree.
Additionally the conditional check to read "mmu-type" from device tree
is not rightly handled due to which the cpu feature doesn't include
CPU_FEAT_MMU even if it's corresponding entry is present in device tree.
We now see correct features as:
=> cpu detail
0: cpu@0 rv64imac
ID = 0, freq = 999.100 MHz
1: cpu@1 rv64imafdc
ID = 1, freq = 999.100 MHz: MMU
2: cpu@2 rv64imafdc
ID = 2, freq = 999.100 MHz: MMU
3: cpu@3 rv64imafdc
ID = 3, freq = 999.100 MHz: MMU
4: cpu@4 rv64imafdc
ID = 4, freq = 999.100 MHz: MMU
Signed-off-by: Sagar Shrikant Kadam <sagar.ka...@sifive.com>
Reviewed-by: Pragnesh Patel <pragnesh.pa...@sifive.com>
---
drivers/cpu/riscv_cpu.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/cpu/riscv_cpu.c b/drivers/cpu/riscv_cpu.c
index 76b0489..8c4b5e7 100644
--- a/drivers/cpu/riscv_cpu.c
+++ b/drivers/cpu/riscv_cpu.c
@@ -38,6 +38,8 @@ static int riscv_cpu_get_info(struct udevice *dev, struct
cpu_info *info)
/* Zero out the frequency, in case sizeof(ulong) != sizeof(u32) */
info->cpu_freq = 0;
+ /* Initialise cpu features before updating from device tree */
+ info->features = 0;
/* First try getting the frequency from the assigned clock */
ret = clk_get_by_index(dev, 0, &clk);
@@ -52,7 +54,7 @@ static int riscv_cpu_get_info(struct udevice *dev, struct
cpu_info *info)
dev_read_u32(dev, "clock-frequency", (u32 *)&info->cpu_freq);
mmu = dev_read_string(dev, "mmu-type");
- if (!mmu)
+ if (mmu)
info->features |= BIT(CPU_FEAT_MMU);
return 0;
--
2.7.4
