>-----Original Message----- >From: Sagar Kadam <sagar.ka...@sifive.com> >Sent: 26 May 2020 22:39 >To: u-boot@lists.denx.de; r...@andestech.com; lu...@denx.de >Cc: ja...@amarulasolutions.com; bmeng...@gmail.com; Pragnesh Patel ><pragnesh.pa...@sifive.com>; sean...@gmail.com; Sagar Kadam ><sagar.ka...@sifive.com> >Subject: [PATCH v2 3/4] riscv: cpu: fixes to display proper CPU features > >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> >--- > drivers/cpu/riscv_cpu.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-)
Reviewed-by: Pragnesh Patel <pragnesh.pa...@sifive.com> > >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
