driver/ddr/fsl: Add workaround for faulty SPD

Some UDIMMs have faulty SPD with wrong mapping for DQ[36-39].
Using raw card spec in case this error is detected.

Signed-off-by: York Sun <yorksun@freescale.com>

diff --git a/drivers/ddr/fsl/ddr4_dimm_params.c b/drivers/ddr/fsl/ddr4_dimm_params.c
index 2418dca6ab9468c729ecd3bcccf81d1d69f05a31..aaddc8fa087d8583b81ce495f2a103ebd07e6845 100644 (file)
--- a/drivers/ddr/fsl/ddr4_dimm_params.c
+++ b/drivers/ddr/fsl/ddr4_dimm_params.c
@@ -126,6 +126,12 @@ ddr_compute_dimm_parameters(const generic_spd_eeprom_t *spd,
 {
        unsigned int retval;
        int i;
+       const u8 udimm_rc_e_dq[18] = {
+               0x0c, 0x2c, 0x15, 0x35, 0x15, 0x35, 0x0b, 0x2c, 0x15,
+               0x35, 0x0b, 0x35, 0x0b, 0x2c, 0x0b, 0x35, 0x15, 0x36
+       };
+       int spd_error = 0;
+       u8 *ptr;
 
        if (spd->mem_type) {
                if (spd->mem_type != SPD_MEMTYPE_DDR4) {
@@ -179,6 +185,22 @@ ddr_compute_dimm_parameters(const generic_spd_eeprom_t *spd,
                /* Unbuffered DIMMs */
                if (spd->mod_section.unbuffered.addr_mapping & 0x1)
                        pdimm->mirrored_dimm = 1;
+               if ((spd->mod_section.unbuffered.mod_height & 0xe0) == 0 &&
+                   (spd->mod_section.unbuffered.ref_raw_card == 0x04)) {
+                       /* Fix SPD error found on DIMMs with raw card E0 */
+                       for (i = 0; i < 18; i++) {
+                               if (spd->mapping[i] == udimm_rc_e_dq[i])
+                                       continue;
+                               spd_error = 1;
+                               debug("SPD byte %d: 0x%x, should be 0x%x\n",
+                                     60 + i, spd->mapping[i],
+                                     udimm_rc_e_dq[i]);
+                               ptr = (u8 *)&spd->mapping[i];
+                               *ptr = udimm_rc_e_dq[i];
+                       }
+                       if (spd_error)
+                               puts("SPD DQ mapping error fixed\n");
+               }
                break;
 
        default: