MIPS: Netlogic: Read memory from DRAM BARs

Read the memory from the Bridge DRAM BARs, if it is not passed in
from the device tree. This will allow us to remove memory configuration
from built in device trees.

Signed-off-by: Jayachandran C <jchandra@broadcom.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/5743/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

4 files changed, 65 insertions, 0 deletions

diff --git a/arch/mips/include/asm/netlogic/xlp-hal/bridge.h b/arch/mips/include/asm/netlogic/xlp-hal/bridge.h
index 790f0f1e55c6..4e8eacb9588a 100644
--- a/arch/mips/include/asm/netlogic/xlp-hal/bridge.h
+++ b/arch/mips/include/asm/netlogic/xlp-hal/bridge.h
@@ -88,6 +88,7 @@
 #define BRIDGE_DRAM_LIMIT6              0x22
 #define BRIDGE_DRAM_LIMIT7              0x23
 
+#define BRIDGE_DRAM_NODE_TRANSLN(i)     (0x24 + (i))
 #define BRIDGE_DRAM_NODE_TRANSLN0       0x24
 #define BRIDGE_DRAM_NODE_TRANSLN1       0x25
 #define BRIDGE_DRAM_NODE_TRANSLN2       0x26
@@ -96,6 +97,8 @@
 #define BRIDGE_DRAM_NODE_TRANSLN5       0x29
 #define BRIDGE_DRAM_NODE_TRANSLN6       0x2a
 #define BRIDGE_DRAM_NODE_TRANSLN7       0x2b
+
+#define BRIDGE_DRAM_CHNL_TRANSLN(i)     (0x2c + (i))
 #define BRIDGE_DRAM_CHNL_TRANSLN0       0x2c
 #define BRIDGE_DRAM_CHNL_TRANSLN1       0x2d
 #define BRIDGE_DRAM_CHNL_TRANSLN2       0x2e
@@ -104,6 +107,7 @@
 #define BRIDGE_DRAM_CHNL_TRANSLN5       0x31
 #define BRIDGE_DRAM_CHNL_TRANSLN6       0x32
 #define BRIDGE_DRAM_CHNL_TRANSLN7       0x33
+
 #define BRIDGE_PCIEMEM_BASE0            0x34
 #define BRIDGE_PCIEMEM_BASE1            0x35
 #define BRIDGE_PCIEMEM_BASE2            0x36
diff --git a/arch/mips/include/asm/netlogic/xlp-hal/xlp.h b/arch/mips/include/asm/netlogic/xlp-hal/xlp.h
index f4ea0f7f3965..d59cdd69496b 100644
--- a/arch/mips/include/asm/netlogic/xlp-hal/xlp.h
+++ b/arch/mips/include/asm/netlogic/xlp-hal/xlp.h
@@ -59,6 +59,9 @@ void xlp_wakeup_secondary_cpus(void);
 
 void xlp_mmu_init(void);
 void nlm_hal_init(void);
+int xlp_get_dram_map(int n, uint64_t *dram_map);
+
+/* Device tree related */
 void *xlp_dt_init(void *fdtp);
 
 #endif /* !__ASSEMBLY__ */
diff --git a/arch/mips/netlogic/xlp/nlm_hal.c b/arch/mips/netlogic/xlp/nlm_hal.c
index 87560e4db35f..6f2c21008ddb 100644
--- a/arch/mips/netlogic/xlp/nlm_hal.c
+++ b/arch/mips/netlogic/xlp/nlm_hal.c
@@ -44,6 +44,7 @@
 #include <asm/netlogic/haldefs.h>
 #include <asm/netlogic/xlp-hal/iomap.h>
 #include <asm/netlogic/xlp-hal/xlp.h>
+#include <asm/netlogic/xlp-hal/bridge.h>
 #include <asm/netlogic/xlp-hal/pic.h>
 #include <asm/netlogic/xlp-hal/sys.h>
 
@@ -142,3 +143,37 @@ unsigned int nlm_get_cpu_frequency(void)
 {
         return nlm_get_core_frequency(0, 0);
 }
+
+/*
+ * Fills upto 8 pairs of entries containing the DRAM map of a node
+ * if n < 0, get dram map for all nodes
+ */
+int xlp_get_dram_map(int n, uint64_t *dram_map)
+{
+        uint64_t bridgebase, base, lim;
+        uint32_t val;
+        int i, node, rv;
+
+        /* Look only at mapping on Node 0, we don't handle crazy configs */
+        bridgebase = nlm_get_bridge_regbase(0);
+        rv = 0;
+        for (i = 0; i < 8; i++) {
+                val = nlm_read_bridge_reg(bridgebase,
+                                        BRIDGE_DRAM_NODE_TRANSLN(i));
+                node = (val >> 1) & 0x3;
+                if (n >= 0 && n != node)
+                        continue;
+                val = nlm_read_bridge_reg(bridgebase, BRIDGE_DRAM_BAR(i));
+                val = (val >>  12) & 0xfffff;
+                base = (uint64_t) val << 20;
+                val = nlm_read_bridge_reg(bridgebase, BRIDGE_DRAM_LIMIT(i));
+                val = (val >>  12) & 0xfffff;
+                if (val == 0)   /* BAR not used */
+                        continue;
+                lim = ((uint64_t)val + 1) << 20;
+                dram_map[rv] = base;
+                dram_map[rv + 1] = lim;
+                rv += 2;
+        }
+        return rv;
+}
diff --git a/arch/mips/netlogic/xlp/setup.c b/arch/mips/netlogic/xlp/setup.c
index 7b638f7be491..7718368e4598 100644
--- a/arch/mips/netlogic/xlp/setup.c
+++ b/arch/mips/netlogic/xlp/setup.c
@@ -73,6 +73,23 @@ static void nlm_fixup_mem(void)
         }
 }
 
+static void __init xlp_init_mem_from_bars(void)
+{
+        uint64_t map[16];
+        int i, n;
+
+        n = xlp_get_dram_map(-1, map);  /* -1: info for all nodes */
+        for (i = 0; i < n; i += 2) {
+                /* exclude 0x1000_0000-0x2000_0000, u-boot device */
+                if (map[i] <= 0x10000000 && map[i+1] > 0x10000000)
+                        map[i+1] = 0x10000000;
+                if (map[i] > 0x10000000 && map[i] < 0x20000000)
+                        map[i] = 0x20000000;
+
+                add_memory_region(map[i], map[i+1] - map[i], BOOT_MEM_RAM);
+        }
+}
+
 void __init plat_mem_setup(void)
 {
         panic_timeout   = 5;
@@ -82,6 +99,12 @@ void __init plat_mem_setup(void)
 
         /* memory and bootargs from DT */
         early_init_devtree(initial_boot_params);
+
+        if (boot_mem_map.nr_map == 0) {
+                pr_info("Using DRAM BARs for memory map.\n");
+                xlp_init_mem_from_bars();
+        }
+        /* Calculate and setup wired entries for mapped kernel */
         nlm_fixup_mem();
 }