[PATCH 07/21] amd64_edac: add sys addr to memory controller mapping helpers

From: Borislav Petkov
Date: Thu May 07 2009 - 09:52:21 EST


From: Doug Thompson <dougthompson@xxxxxxxxxxxx>

Reviewed-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>
Signed-off-by: Doug Thompson <dougthompson@xxxxxxxxxxxx>
Signed-off-by: Borislav Petkov <borislav.petkov@xxxxxxx>
---
drivers/edac/amd64_edac.c | 164 +++++++++++++++++++++++++++++++++++++++++++++
1 files changed, 164 insertions(+), 0 deletions(-)

diff --git a/drivers/edac/amd64_edac.c b/drivers/edac/amd64_edac.c
index df72ecc..44aa102 100644
--- a/drivers/edac/amd64_edac.c
+++ b/drivers/edac/amd64_edac.c
@@ -132,3 +132,167 @@ static int amd64_get_scrub_rate(struct mem_ctl_info *mci, u32 *bw)
return status;
}

+/*
+ * amd64_map_to_dcs_mask
+ *
+ * Map from a CSROW entry to the mask entry that operates on it
+ */
+static inline u32 amd64_map_to_dcs_mask(struct amd64_pvt *pvt, int csrow)
+{
+ return csrow >> (pvt->num_dcsm >> 3);
+}
+
+/*
+ * amd64_get_dct_base()
+ *
+ * getter function to return the 'base' address the i'th CS entry
+ * of the 'dct' DRAM controller
+ */
+static u32 amd64_get_dct_base(struct amd64_pvt *pvt, int dct, int csrow)
+{
+ if (dct == 0)
+ return pvt->dcsb0[csrow];
+ else
+ return pvt->dcsb1[csrow];
+}
+
+/*
+ * amd64_get_dct_mask()
+ *
+ * getter function to return the 'mask' address the i'th CS entry.
+ * This getter function is needed because there different number
+ * of DCSM registers on Rev E and prior vs Rev F and later
+ */
+static u32 amd64_get_dct_mask(struct amd64_pvt *pvt, int dct, int csrow)
+{
+ if (dct == 0)
+ return pvt->dcsm0[amd64_map_to_dcs_mask(pvt, csrow)];
+ else
+ return pvt->dcsm1[amd64_map_to_dcs_mask(pvt, csrow)];
+}
+
+
+/*
+ * amd64_get_base_and_limit()
+ *
+ * In *base and *limit, pass back the full 40-bit base and limit physical
+ * addresses for the node given by node_id. This information is obtained from
+ * DRAM Base (section 3.4.4.1) and DRAM Limit (section 3.4.4.2) registers. The
+ * base and limit addresses are of type SysAddr, as defined at the start of
+ * section 3.4.4 (p. 70). They are the lowest and highest physical addresses
+ * in the address range they represent.
+ */
+static void amd64_get_base_and_limit(struct amd64_pvt *pvt, int node_id,
+ u64 *base, u64 *limit)
+{
+ *base = pvt->dram_base[node_id];
+ *limit = pvt->dram_limit[node_id];
+}
+
+/*
+ * Return 1 if the SysAddr given by sys_addr matches the base/limit associated
+ * with node_id
+ */
+static int amd64_base_limit_match(struct amd64_pvt *pvt,
+ u64 sys_addr, int node_id)
+{
+ u64 base, limit, addr;
+
+ amd64_get_base_and_limit(pvt, node_id, &base, &limit);
+
+ /* The K8 treats this as a 40-bit value. However, bits 63-40 will be
+ * all ones if the most significant implemented address bit is 1.
+ * Here we discard bits 63-40. See section 3.4.2 of AMD publication
+ * 24592: AMD x86-64 Architecture Programmer's Manual Volume 1
+ * Application Programming.
+ */
+ addr = sys_addr & 0x000000ffffffffffull;
+
+ return (addr >= base) && (addr <= limit);
+}
+
+/* find_mc_by_sys_addr
+ *
+ * Attempt to map a SysAddr to a node.
+ *
+ * On success, return a pointer to the mem_ctl_info structure for
+ * the node that the SysAddr maps to.
+ *
+ * On failure, return NULL
+ */
+static struct mem_ctl_info *find_mc_by_sys_addr(struct mem_ctl_info *mci,
+ u64 sys_addr)
+{
+ struct amd64_pvt *pvt;
+ int node_id;
+ u32 intlv_en, bits;
+
+ /*
+ * Here we use the DRAM Base (section 3.4.4.1) and DRAM Limit (section
+ * 3.4.4.2) registers to map the SysAddr to a node ID.
+ */
+ pvt = mci->pvt_info;
+
+ /* The value of this field should be the same for all DRAM Base
+ * registers. Therefore we arbitrarily choose to read it from the
+ * register for node 0.
+ */
+ intlv_en = pvt->dram_IntlvEn[0];
+
+ if (intlv_en == 0) {
+ debugf2("%s(): node interleaving disabled\n", __func__);
+ for (node_id = 0; ; ) {
+ if (amd64_base_limit_match(pvt, sys_addr, node_id))
+ break;
+
+ if (++node_id >= DRAM_REG_COUNT) {
+ debugf2("%s(): sys_addr 0x%lx "
+ "does not match any node\n", __func__,
+ (unsigned long)sys_addr);
+ return NULL;
+ }
+ }
+
+ goto found;
+ }
+
+ if (unlikely((intlv_en != (0x01 << 8)) &&
+ (intlv_en != (0x03 << 8)) && (intlv_en != (0x07 << 8)))) {
+ amd64_printk(KERN_WARNING,
+ "%s(): junk value of 0x%x extracted from IntlvEn "
+ "field of DRAM Base Register for node 0: This "
+ "probably indicates a BIOS bug.\n", __func__,
+ intlv_en);
+ return NULL;
+ }
+
+ debugf2("%s(): node interleaving enabled\n", __func__);
+ bits = (((u32) sys_addr) >> 12) & intlv_en;
+
+ for (node_id = 0; ; ) {
+ if ((pvt->dram_limit[node_id] & intlv_en) == bits)
+ break; /* intlv_sel field matches */
+
+ if (++node_id >= DRAM_REG_COUNT) {
+ debugf2("%s(): sys_addr 0x%lx does not match any "
+ "node\n", __func__, (unsigned long)sys_addr);
+ return NULL;
+ }
+ }
+
+ /* sanity test for sys_addr */
+ if (unlikely(!amd64_base_limit_match(pvt, sys_addr, node_id))) {
+ amd64_printk(KERN_WARNING,
+ "%s(): sys_addr 0x%lx falls outside base/limit "
+ "address range for node %d with node interleaving "
+ "enabled.\n", __func__, (unsigned long)sys_addr,
+ node_id);
+ return NULL;
+ }
+
+found:
+ debugf2("%s(): sys_addr 0x%lx matches node %d\n", __func__,
+ (unsigned long)sys_addr, node_id);
+
+ return edac_mc_find(node_id);
+}
--
1.6.2.4


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