Re: [PATCH V4] edac, amd64_edac: Modify usage of amd64_read_dct_pci_cfg()

From: Borislav Petkov
Date: Mon Sep 15 2014 - 08:09:34 EST

On Tue, Sep 09, 2014 at 02:52:26PM -0500, Aravind Gopalakrishnan wrote:
> Rationale behind this change:
> - F2x1xx addresses were stopped from being mapped explicitly to DCT1
> from F15h (OR) onwards. They use _dct[0:1] mechanism to access the
> registers. So we should move away from using address ranges to select
> DCT for these families.
> - On newer processors, the address ranges used to indicate DCT1 (0x140,
> 0x1a0) have different meanings than what is assumed currently.
>
> Changes introduced:
> - amd64_read_dct_pci_cfg() now takes in dct value and uses it for
> 'selecting the dct'
> - Update usage of the function. Keep in mind that different families
> have specific handling requirements
> - Remove [k8|f10]_read_dct_pci_cfg() as they don't do much different
> from amd64_read_pci_cfg()
> - Move the k8 specific check to amd64_read_pci_cfg
> - Remove f15_read_dct_pci_cfg() and move logic to amd64_read_dct_pci_cfg()
> - Remove now needless .read_dct_pci_cfg
>
> Testing:
> - Tested on Fam 10h; Fam15h Models: 00h, 30h; Fam16h using 'EDAC_DEBUG'
> and mce_amd_inj
> - driver obtains info from F2x registers and caches it in pvt
> structures correctly
> - ECC decoding works fine
>
> Signed-off-by: Aravind Gopalakrishnan <aravind.gopalakrishnan@xxxxxxx>
> ---
> Change in V4:
> - move amd64_read_dct_pci_cfg() to amd64_edac.c and save exporting
> f15h_select_dct() in the process
>
> Changes in V3:
> - per Boris suggestion
> - move dct selection logic to amd64_read_dct_pci_cfg()
> - remove f15_read_dct_pci_cfg() and move logic to amd64_read_dct_pci_cfg()
> - misc
> - modify logic in amd64_read_dct_pci_cfg() to keep in mind the specific
> read handling requirements of different families. Previous version had
> failed to do that.
>
> Changes in V2: (per Boris suggestion)
> - Hide family checks in amd64_read_dct_pci_cfg()
> - Use pvt structure for family checks and not boot_cpu_data
>
> drivers/edac/amd64_edac.c | 138 +++++++++++++++++++++++-----------------------
> drivers/edac/amd64_edac.h | 5 --
> 2 files changed, 68 insertions(+), 75 deletions(-)
>
> diff --git a/drivers/edac/amd64_edac.c b/drivers/edac/amd64_edac.c
> index f8bf000..b39d1b0 100644
> --- a/drivers/edac/amd64_edac.c
> +++ b/drivers/edac/amd64_edac.c
> @@ -87,35 +87,6 @@ int __amd64_write_pci_cfg_dword(struct pci_dev *pdev, int offset,
> }
>
> /*
> - *
> - * Depending on the family, F2 DCT reads need special handling:
> - *
> - * K8: has a single DCT only
> - *
> - * F10h: each DCT has its own set of regs
> - * DCT0 -> F2x040..
> - * DCT1 -> F2x140..
> - *
> - * F15h: we select which DCT we access using F1x10C[DctCfgSel]
> - *
> - * F16h: has only 1 DCT
> - */
> -static int k8_read_dct_pci_cfg(struct amd64_pvt *pvt, int addr, u32 *val,
> - const char *func)
> -{
> - if (addr >= 0x100)
> - return -EINVAL;
> -
> - return __amd64_read_pci_cfg_dword(pvt->F2, addr, val, func);
> -}
> -
> -static int f10_read_dct_pci_cfg(struct amd64_pvt *pvt, int addr, u32 *val,
> - const char *func)
> -{
> - return __amd64_read_pci_cfg_dword(pvt->F2, addr, val, func);
> -}
> -
> -/*
> * Select DCT to which PCI cfg accesses are routed
> */
> static void f15h_select_dct(struct amd64_pvt *pvt, u8 dct)
> @@ -123,25 +94,51 @@ static void f15h_select_dct(struct amd64_pvt *pvt, u8 dct)
> u32 reg = 0;
>
> amd64_read_pci_cfg(pvt->F1, DCT_CFG_SEL, &reg);
> - reg &= (pvt->model >= 0x30) ? ~3 : ~1;
> + reg &= (pvt->model == 0x30) ? ~3 : ~1;
> reg |= dct;
> amd64_write_pci_cfg(pvt->F1, DCT_CFG_SEL, reg);
> }
>
> -static int f15_read_dct_pci_cfg(struct amd64_pvt *pvt, int addr, u32 *val,
> - const char *func)
> +/*
> + *
> + * Depending on the family, F2 DCT reads need special handling:
> + *
> + * K8: has a single DCT only and no address offsets >= 0x100
> + *
> + * F10h: each DCT has its own set of regs
> + * DCT0 -> F2x040..
> + * DCT1 -> F2x140..
> + *
> + * F16h: has only 1 DCT
> + */
> +static inline int amd64_read_dct_pci_cfg(struct amd64_pvt *pvt, u8 dct,
> + int offset, u32 *val)
> {
> - u8 dct = 0;
> + if (pvt->fam == 0xf) {
> + if (dct || offset >= 0x100)
> + return -EINVAL;
> + } else if (pvt->fam == 0x10 && dct) {
> + /*
> + * Note: If ganging is enabled, barring the regs
> + * F2x[1,0]98 and F2x[1,0]9C; reads reads to F2x1xx

Why aren't we dealing with those registers here then?

Btw, let's do this function with a switch-case, for better
readability:

static inline int amd64_read_dct_pci_cfg(struct amd64_pvt *pvt, u8 dct,
int offset, u32 *val)
{
switch (pvt->fam) {
case 0xf:
if (dct || offset >= 0x100)
return -EINVAL;
break;

case 0x10:
if (dct) {
/*
* Note: If ganging is enabled, barring the regs
* F2x[1,0]98 and F2x[1,0]9C; reads reads to F2x1xx
* return 0. (cf. Section 2.8.1 F10h BKDG)
*/
if (dct_ganging_enabled(pvt))
return 0;

offset += 0x100;
}
break;

case 0x15:
/*
* F15h: F2x1xx addresses do not map explicitly to DCT1.
* We should select which DCT we access using F1x10C[DctCfgSel]
*/
dct = (dct && pvt->model == 0x30) ? 3 : dct;
f15h_select_dct(pvt, dct);
break;

case 0x16:
if (dct)
return -EINVAL;
break;

default:
break;
}
return amd64_read_pci_cfg(pvt->F2, offset, val);
}


> + * return 0. (cf. Section 2.8.1 F10h BKDG)
> + */
> + if (dct_ganging_enabled(pvt))
> + return 0;
>
> - /* For F15 M30h, the second dct is DCT 3, refer to BKDG Section 2.10 */
> - if (addr >= 0x140 && addr <= 0x1a0) {
> - dct = (pvt->model >= 0x30) ? 3 : 1;
> - addr -= 0x100;
> - }
> + offset += 0x100;
> + } else if (pvt->fam == 0x15) {
> + /*
> + * F15h: F2x1xx addresses do not map explicitly to DCT1.
> + * We should select which DCT we access using F1x10C[DctCfgSel]
> + */
> + dct = (dct && pvt->model == 0x30) ? 3 : dct;
> + f15h_select_dct(pvt, dct);
>
> - f15h_select_dct(pvt, dct);
> + } else if (pvt->fam == 0x16 && dct)
> + return -EINVAL;
>
> - return __amd64_read_pci_cfg_dword(pvt->F2, addr, val, func);
> + return amd64_read_pci_cfg(pvt->F2, offset, val);
> }
>

...

> @@ -768,16 +765,17 @@ static void read_dct_base_mask(struct amd64_pvt *pvt)
> u32 *base0 = &pvt->csels[0].csbases[cs];
> u32 *base1 = &pvt->csels[1].csbases[cs];
>
> - if (!amd64_read_dct_pci_cfg(pvt, reg0, base0))
> + if (!amd64_read_dct_pci_cfg(pvt, 0, reg0, base0))
> edac_dbg(0, " DCSB0[%d]=0x%08x reg: F2x%x\n",
> cs, *base0, reg0);
>
> - if (pvt->fam == 0xf || dct_ganging_enabled(pvt))
> + if (pvt->fam == 0xf)
> continue;
>
> - if (!amd64_read_dct_pci_cfg(pvt, reg1, base1))
> + if (!amd64_read_dct_pci_cfg(pvt, 1, reg0, base1))
> edac_dbg(0, " DCSB1[%d]=0x%08x reg: F2x%x\n",
> - cs, *base1, reg1);
> + cs, *base1, (pvt->fam == 0x10) ? reg1
> + : reg0);
> }
>
> for_each_chip_select_mask(cs, 0, pvt) {
> @@ -786,16 +784,17 @@ static void read_dct_base_mask(struct amd64_pvt *pvt)
> u32 *mask0 = &pvt->csels[0].csmasks[cs];
> u32 *mask1 = &pvt->csels[1].csmasks[cs];
>
> - if (!amd64_read_dct_pci_cfg(pvt, reg0, mask0))
> + if (!amd64_read_dct_pci_cfg(pvt, 0, reg0, mask0))
> edac_dbg(0, " DCSM0[%d]=0x%08x reg: F2x%x\n",
> cs, *mask0, reg0);
>
> - if (pvt->fam == 0xf || dct_ganging_enabled(pvt))
> + if (pvt->fam == 0xf)
> continue;
>
> - if (!amd64_read_dct_pci_cfg(pvt, reg1, mask1))
> + if (!amd64_read_dct_pci_cfg(pvt, 1, reg0, mask1))
> edac_dbg(0, " DCSM1[%d]=0x%08x reg: F2x%x\n",
> - cs, *mask1, reg1);
> + cs, *mask1, (pvt->fam == 0x10) ? reg1
> + : reg0);
> }
> }
>
> @@ -1198,7 +1197,7 @@ static void read_dram_ctl_register(struct amd64_pvt *pvt)
> if (pvt->fam == 0xf)
> return;
>
> - if (!amd64_read_dct_pci_cfg(pvt, DCT_SEL_LO, &pvt->dct_sel_lo)) {
> + if (!amd64_read_pci_cfg(pvt->F2, DCT_SEL_LO, &pvt->dct_sel_lo)) {
> edac_dbg(0, "F2x110 (DCTSelLow): 0x%08x, High range addrs at: 0x%x\n",
> pvt->dct_sel_lo, dct_sel_baseaddr(pvt));
>
> @@ -1219,7 +1218,7 @@ static void read_dram_ctl_register(struct amd64_pvt *pvt)
> dct_sel_interleave_addr(pvt));
> }
>
> - amd64_read_dct_pci_cfg(pvt, DCT_SEL_HI, &pvt->dct_sel_hi);
> + amd64_read_pci_cfg(pvt->F2, DCT_SEL_HI, &pvt->dct_sel_hi);
> }
>
> /*
> @@ -1430,7 +1429,7 @@ static u64 f1x_swap_interleaved_region(struct amd64_pvt *pvt, u64 sys_addr)
> return sys_addr;
> }
>
> - amd64_read_dct_pci_cfg(pvt, SWAP_INTLV_REG, &swap_reg);
> + amd64_read_pci_cfg(pvt->F2, SWAP_INTLV_REG, &swap_reg);
>
> if (!(swap_reg & 0x1))
> return sys_addr;
> @@ -1723,9 +1722,16 @@ static void debug_display_dimm_sizes(struct amd64_pvt *pvt, u8 ctrl)
> WARN_ON(ctrl != 0);
> }
>
> - dbam = (ctrl && !dct_ganging_enabled(pvt)) ? pvt->dbam1 : pvt->dbam0;
> - dcsb = (ctrl && !dct_ganging_enabled(pvt)) ? pvt->csels[1].csbases
> - : pvt->csels[0].csbases;
> + if (pvt->fam == 0x10) {
> + dbam = (ctrl && !dct_ganging_enabled(pvt)) ? pvt->dbam1
> + : pvt->dbam0;
> + dcsb = (ctrl && !dct_ganging_enabled(pvt)) ?
> + pvt->csels[1].csbases :
> + pvt->csels[0].csbases;
> + } else if (ctrl) {
> + dbam = pvt->dbam0;
> + dcsb = pvt->csels[1].csbases;
> + }
>
> edac_dbg(1, "F2x%d80 (DRAM Bank Address Mapping): 0x%08x\n",
> ctrl, dbam);
> @@ -1760,7 +1766,6 @@ static struct amd64_family_type family_types[] = {
> .early_channel_count = k8_early_channel_count,
> .map_sysaddr_to_csrow = k8_map_sysaddr_to_csrow,
> .dbam_to_cs = k8_dbam_to_chip_select,
> - .read_dct_pci_cfg = k8_read_dct_pci_cfg,
> }
> },
> [F10_CPUS] = {
> @@ -1771,7 +1776,6 @@ static struct amd64_family_type family_types[] = {
> .early_channel_count = f1x_early_channel_count,
> .map_sysaddr_to_csrow = f1x_map_sysaddr_to_csrow,
> .dbam_to_cs = f10_dbam_to_chip_select,
> - .read_dct_pci_cfg = f10_read_dct_pci_cfg,
> }
> },
> [F15_CPUS] = {
> @@ -1782,7 +1786,6 @@ static struct amd64_family_type family_types[] = {
> .early_channel_count = f1x_early_channel_count,
> .map_sysaddr_to_csrow = f1x_map_sysaddr_to_csrow,
> .dbam_to_cs = f15_dbam_to_chip_select,
> - .read_dct_pci_cfg = f15_read_dct_pci_cfg,
> }
> },
> [F15_M30H_CPUS] = {
> @@ -1793,7 +1796,6 @@ static struct amd64_family_type family_types[] = {
> .early_channel_count = f1x_early_channel_count,
> .map_sysaddr_to_csrow = f1x_map_sysaddr_to_csrow,
> .dbam_to_cs = f16_dbam_to_chip_select,
> - .read_dct_pci_cfg = f15_read_dct_pci_cfg,
> }
> },
> [F16_CPUS] = {
> @@ -1804,7 +1806,6 @@ static struct amd64_family_type family_types[] = {
> .early_channel_count = f1x_early_channel_count,
> .map_sysaddr_to_csrow = f1x_map_sysaddr_to_csrow,
> .dbam_to_cs = f16_dbam_to_chip_select,
> - .read_dct_pci_cfg = f10_read_dct_pci_cfg,
> }
> },
> [F16_M30H_CPUS] = {
> @@ -1815,7 +1816,6 @@ static struct amd64_family_type family_types[] = {
> .early_channel_count = f1x_early_channel_count,
> .map_sysaddr_to_csrow = f1x_map_sysaddr_to_csrow,
> .dbam_to_cs = f16_dbam_to_chip_select,
> - .read_dct_pci_cfg = f10_read_dct_pci_cfg,
> }
> },
> };
> @@ -2148,25 +2148,23 @@ static void read_mc_regs(struct amd64_pvt *pvt)
> read_dct_base_mask(pvt);
>
> amd64_read_pci_cfg(pvt->F1, DHAR, &pvt->dhar);
> - amd64_read_dct_pci_cfg(pvt, DBAM0, &pvt->dbam0);
> + amd64_read_dct_pci_cfg(pvt, 0, DBAM0, &pvt->dbam0);
>
> amd64_read_pci_cfg(pvt->F3, F10_ONLINE_SPARE, &pvt->online_spare);
>
> - amd64_read_dct_pci_cfg(pvt, DCLR0, &pvt->dclr0);
> - amd64_read_dct_pci_cfg(pvt, DCHR0, &pvt->dchr0);
> -
> - if (!dct_ganging_enabled(pvt)) {
> - amd64_read_dct_pci_cfg(pvt, DCLR1, &pvt->dclr1);
> - amd64_read_dct_pci_cfg(pvt, DCHR1, &pvt->dchr1);
> - }
> + amd64_read_dct_pci_cfg(pvt, 0, DCLR0, &pvt->dclr0);
> + amd64_read_dct_pci_cfg(pvt, 0, DCHR0, &pvt->dchr0);
>
> pvt->ecc_sym_sz = 4;
>
> if (pvt->fam >= 0x10) {
> + amd64_read_dct_pci_cfg(pvt, 1, DCLR0, &pvt->dclr1);
> + amd64_read_dct_pci_cfg(pvt, 1, DCHR0, &pvt->dchr1);

This doesn't look equivalent - above we're checking whether we're ganged
now you're doing it for >= F10h. Why?

Because only F10h supports ganging?

> +
> amd64_read_pci_cfg(pvt->F3, EXT_NB_MCA_CFG, &tmp);
> + /* F16h has only DCT0, so no need to read dbam1 */
> if (pvt->fam != 0x16)
> - /* F16h has only DCT0 */
> - amd64_read_dct_pci_cfg(pvt, DBAM1, &pvt->dbam1);
> + amd64_read_dct_pci_cfg(pvt, 1, DBAM0, &pvt->dbam1);
>
> /* F10h, revD and later can do x8 ECC too */
> if ((pvt->fam > 0x10 || pvt->model > 7) && tmp & BIT(25))
> diff --git a/drivers/edac/amd64_edac.h b/drivers/edac/amd64_edac.h
> index d903e0c..55fb594 100644
> --- a/drivers/edac/amd64_edac.h
> +++ b/drivers/edac/amd64_edac.h
> @@ -481,8 +481,6 @@ struct low_ops {
> 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, unsigned cs_mode);
> - int (*read_dct_pci_cfg) (struct amd64_pvt *pvt, int offset,
> - u32 *val, const char *func);
> };
>
> struct amd64_family_type {
> @@ -502,9 +500,6 @@ int __amd64_write_pci_cfg_dword(struct pci_dev *pdev, int offset,
> #define amd64_write_pci_cfg(pdev, offset, val) \
> __amd64_write_pci_cfg_dword(pdev, offset, val, __func__)
>
> -#define amd64_read_dct_pci_cfg(pvt, offset, val) \
> - pvt->ops->read_dct_pci_cfg(pvt, offset, val, __func__)
> -
> int amd64_get_dram_hole_info(struct mem_ctl_info *mci, u64 *hole_base,
> u64 *hole_offset, u64 *hole_size);
>
> --
> 2.0.3
>
>

--
Regards/Gruss,
Boris.
--
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