[PATCH v2 05/22] EDAC/amd64: Remove early_channel_count()

From: Yazen Ghannam
Date: Fri Jan 27 2023 - 12:06:42 EST


The early_channel_count() function seems to have been useful in the past
for knowing how many EDAC mci structures to populate. However, this is no
longer needed as the maximum channel count for a system is used instead.

Remove the early_channel_count() helper functions and related code. Use the
size of the channel layer when iterating over channel structures.

Signed-off-by: Yazen Ghannam <yazen.ghannam@xxxxxxx>
---
Link:
https://lore.kernel.org/r/20220509145534.44912-1-yazen.ghannam@xxxxxxx

v1->v2:
* New in v2.

drivers/edac/amd64_edac.c | 116 +-------------------------------------
drivers/edac/amd64_edac.h | 2 -
2 files changed, 2 insertions(+), 116 deletions(-)

diff --git a/drivers/edac/amd64_edac.c b/drivers/edac/amd64_edac.c
index 352cbcda53f9..1c4bef1cdf28 100644
--- a/drivers/edac/amd64_edac.c
+++ b/drivers/edac/amd64_edac.c
@@ -1703,24 +1703,6 @@ static void determine_memory_type(struct amd64_pvt *pvt)
pvt->dram_type = (pvt->dclr0 & BIT(16)) ? MEM_DDR3 : MEM_RDDR3;
}

-/* Get the number of DCT channels the memory controller is using. */
-static int k8_early_channel_count(struct amd64_pvt *pvt)
-{
- int flag;
-
- if (pvt->ext_model >= K8_REV_F)
- /* RevF (NPT) and later */
- flag = pvt->dclr0 & WIDTH_128;
- else
- /* RevE and earlier */
- flag = pvt->dclr0 & REVE_WIDTH_128;
-
- /* not used */
- pvt->dclr1 = 0;
-
- return (flag) ? 2 : 1;
-}
-
/* On F10h and later ErrAddr is MC4_ADDR[47:1] */
static u64 get_error_address(struct amd64_pvt *pvt, struct mce *m)
{
@@ -1972,69 +1954,6 @@ static int k8_dbam_to_chip_select(struct amd64_pvt *pvt, u8 dct,
}
}

-/*
- * Get the number of DCT channels in use.
- *
- * Return:
- * number of Memory Channels in operation
- * Pass back:
- * contents of the DCL0_LOW register
- */
-static int f1x_early_channel_count(struct amd64_pvt *pvt)
-{
- int i, j, channels = 0;
-
- /* On F10h, if we are in 128 bit mode, then we are using 2 channels */
- if (pvt->fam == 0x10 && (pvt->dclr0 & WIDTH_128))
- return 2;
-
- /*
- * Need to check if in unganged mode: In such, there are 2 channels,
- * but they are not in 128 bit mode and thus the above 'dclr0' status
- * bit will be OFF.
- *
- * Need to check DCT0[0] and DCT1[0] to see if only one of them has
- * their CSEnable bit on. If so, then SINGLE DIMM case.
- */
- edac_dbg(0, "Data width is not 128 bits - need more decoding\n");
-
- /*
- * Check DRAM Bank Address Mapping values for each DIMM to see if there
- * is more than just one DIMM present in unganged mode. Need to check
- * both controllers since DIMMs can be placed in either one.
- */
- for (i = 0; i < 2; i++) {
- u32 dbam = (i ? pvt->dbam1 : pvt->dbam0);
-
- for (j = 0; j < 4; j++) {
- if (DBAM_DIMM(j, dbam) > 0) {
- channels++;
- break;
- }
- }
- }
-
- if (channels > 2)
- channels = 2;
-
- amd64_info("MCT channel count: %d\n", channels);
-
- return channels;
-}
-
-static int f17_early_channel_count(struct amd64_pvt *pvt)
-{
- int i, channels = 0;
-
- /* SDP Control bit 31 (SdpInit) is clear for unused UMC channels */
- for_each_umc(i)
- channels += !!(pvt->umc[i].sdp_ctrl & UMC_SDP_INIT);
-
- amd64_info("MCT channel count: %d\n", channels);
-
- return channels;
-}
-
static int ddr3_cs_size(unsigned i, bool dct_width)
{
unsigned shift = 0;
@@ -2829,7 +2748,6 @@ static struct amd64_family_type family_types[] = {
.f2_id = PCI_DEVICE_ID_AMD_K8_NB_MEMCTL,
.max_mcs = 2,
.ops = {
- .early_channel_count = k8_early_channel_count,
.map_sysaddr_to_csrow = k8_map_sysaddr_to_csrow,
.dbam_to_cs = k8_dbam_to_chip_select,
}
@@ -2840,7 +2758,6 @@ static struct amd64_family_type family_types[] = {
.f2_id = PCI_DEVICE_ID_AMD_10H_NB_DRAM,
.max_mcs = 2,
.ops = {
- .early_channel_count = f1x_early_channel_count,
.map_sysaddr_to_csrow = f1x_map_sysaddr_to_csrow,
.dbam_to_cs = f10_dbam_to_chip_select,
}
@@ -2851,7 +2768,6 @@ static struct amd64_family_type family_types[] = {
.f2_id = PCI_DEVICE_ID_AMD_15H_NB_F2,
.max_mcs = 2,
.ops = {
- .early_channel_count = f1x_early_channel_count,
.map_sysaddr_to_csrow = f1x_map_sysaddr_to_csrow,
.dbam_to_cs = f15_dbam_to_chip_select,
}
@@ -2862,7 +2778,6 @@ static struct amd64_family_type family_types[] = {
.f2_id = PCI_DEVICE_ID_AMD_15H_M30H_NB_F2,
.max_mcs = 2,
.ops = {
- .early_channel_count = f1x_early_channel_count,
.map_sysaddr_to_csrow = f1x_map_sysaddr_to_csrow,
.dbam_to_cs = f16_dbam_to_chip_select,
}
@@ -2873,7 +2788,6 @@ static struct amd64_family_type family_types[] = {
.f2_id = PCI_DEVICE_ID_AMD_15H_M60H_NB_F2,
.max_mcs = 2,
.ops = {
- .early_channel_count = f1x_early_channel_count,
.map_sysaddr_to_csrow = f1x_map_sysaddr_to_csrow,
.dbam_to_cs = f15_m60h_dbam_to_chip_select,
}
@@ -2884,7 +2798,6 @@ static struct amd64_family_type family_types[] = {
.f2_id = PCI_DEVICE_ID_AMD_16H_NB_F2,
.max_mcs = 2,
.ops = {
- .early_channel_count = f1x_early_channel_count,
.map_sysaddr_to_csrow = f1x_map_sysaddr_to_csrow,
.dbam_to_cs = f16_dbam_to_chip_select,
}
@@ -2895,7 +2808,6 @@ static struct amd64_family_type family_types[] = {
.f2_id = PCI_DEVICE_ID_AMD_16H_M30H_NB_F2,
.max_mcs = 2,
.ops = {
- .early_channel_count = f1x_early_channel_count,
.map_sysaddr_to_csrow = f1x_map_sysaddr_to_csrow,
.dbam_to_cs = f16_dbam_to_chip_select,
}
@@ -2904,7 +2816,6 @@ static struct amd64_family_type family_types[] = {
.ctl_name = "F17h",
.max_mcs = 2,
.ops = {
- .early_channel_count = f17_early_channel_count,
.dbam_to_cs = f17_addr_mask_to_cs_size,
}
},
@@ -2912,7 +2823,6 @@ static struct amd64_family_type family_types[] = {
.ctl_name = "F17h_M10h",
.max_mcs = 2,
.ops = {
- .early_channel_count = f17_early_channel_count,
.dbam_to_cs = f17_addr_mask_to_cs_size,
}
},
@@ -2920,7 +2830,6 @@ static struct amd64_family_type family_types[] = {
.ctl_name = "F17h_M30h",
.max_mcs = 8,
.ops = {
- .early_channel_count = f17_early_channel_count,
.dbam_to_cs = f17_addr_mask_to_cs_size,
}
},
@@ -2928,7 +2837,6 @@ static struct amd64_family_type family_types[] = {
.ctl_name = "F17h_M60h",
.max_mcs = 2,
.ops = {
- .early_channel_count = f17_early_channel_count,
.dbam_to_cs = f17_addr_mask_to_cs_size,
}
},
@@ -2936,7 +2844,6 @@ static struct amd64_family_type family_types[] = {
.ctl_name = "F17h_M70h",
.max_mcs = 2,
.ops = {
- .early_channel_count = f17_early_channel_count,
.dbam_to_cs = f17_addr_mask_to_cs_size,
}
},
@@ -2944,7 +2851,6 @@ static struct amd64_family_type family_types[] = {
.ctl_name = "F19h",
.max_mcs = 8,
.ops = {
- .early_channel_count = f17_early_channel_count,
.dbam_to_cs = f17_addr_mask_to_cs_size,
}
},
@@ -2953,7 +2859,6 @@ static struct amd64_family_type family_types[] = {
.max_mcs = 12,
.flags.zn_regs_v2 = 1,
.ops = {
- .early_channel_count = f17_early_channel_count,
.dbam_to_cs = f17_addr_mask_to_cs_size,
}
},
@@ -2961,7 +2866,6 @@ static struct amd64_family_type family_types[] = {
.ctl_name = "F19h_M50h",
.max_mcs = 2,
.ops = {
- .early_channel_count = f17_early_channel_count,
.dbam_to_cs = f17_addr_mask_to_cs_size,
}
},
@@ -3620,7 +3524,7 @@ static int init_csrows(struct mem_ctl_info *mci)
: EDAC_SECDED;
}

- for (j = 0; j < pvt->channel_count; j++) {
+ for (j = 0; j < fam_type->max_mcs; j++) {
dimm = csrow->channels[j]->dimm;
dimm->mtype = pvt->dram_type;
dimm->edac_mode = edac_mode;
@@ -4057,28 +3961,12 @@ static int init_one_instance(struct amd64_pvt *pvt)
{
struct mem_ctl_info *mci = NULL;
struct edac_mc_layer layers[2];
- int ret = -EINVAL;
+ int ret = -ENOMEM;

- /*
- * We need to determine how many memory channels there are. Then use
- * that information for calculating the size of the dynamic instance
- * tables in the 'mci' structure.
- */
- pvt->channel_count = pvt->ops->early_channel_count(pvt);
- if (pvt->channel_count < 0)
- return ret;
-
- ret = -ENOMEM;
layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
layers[0].size = pvt->csels[0].b_cnt;
layers[0].is_virt_csrow = true;
layers[1].type = EDAC_MC_LAYER_CHANNEL;
-
- /*
- * Always allocate two channels since we can have setups with DIMMs on
- * only one channel. Also, this simplifies handling later for the price
- * of a couple of KBs tops.
- */
layers[1].size = fam_type->max_mcs;
layers[1].is_virt_csrow = false;

diff --git a/drivers/edac/amd64_edac.h b/drivers/edac/amd64_edac.h
index 398fb58dacbf..e4329dff8cf2 100644
--- a/drivers/edac/amd64_edac.h
+++ b/drivers/edac/amd64_edac.h
@@ -346,7 +346,6 @@ struct amd64_pvt {
u8 stepping; /* ... stepping */

int ext_model; /* extended model value of this node */
- int channel_count;

/* Raw registers */
u32 dclr0; /* DRAM Configuration Low DCT0 reg */
@@ -466,7 +465,6 @@ struct ecc_settings {
* functions and per device encoding/decoding logic.
*/
struct low_ops {
- int (*early_channel_count) (struct amd64_pvt *pvt);
void (*map_sysaddr_to_csrow) (struct mem_ctl_info *mci, u64 sys_addr,
struct err_info *);
int (*dbam_to_cs) (struct amd64_pvt *pvt, u8 dct,
--
2.25.1