linux/drivers/soc/qcom/smem_dramc.c
Konrad Dybcio 1d234eeafc soc: qcom: smem: Expose DDR data from SMEM
Most modern Qualcomm platforms (>= SM8150) expose information about the
DDR memory present on the system via SMEM.

Details from this information is used in various scenarios, such as
multimedia drivers configuring the hardware based on the "Highest Bank
address Bit" (hbb), or the list of valid frequencies in validation
scenarios...

Add support for parsing v3-v7 version of the structs. Unforunately,
they are not versioned, so some elbow grease is necessary to determine
which one is present. See for reference:

ver 3: 1d11897d2c
ver 4: f6e9aa5492
ver 5: 617d3297ab
ver 5 with 6regions: d770e009f9
ver 6: 62659b557f
ver 7: 734d95599c

Reviewed-by: Bjorn Andersson <andersson@kernel.org>
Signed-off-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Link: 1d11897d2c
Link: https://lore.kernel.org/r/20260727-topic-smem_dramc-v5-2-66188b3e338d@oss.qualcomm.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
2026-07-30 17:05:46 -05:00

431 lines
11 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) Qualcomm Technologies, Inc. and/or its subsidiaries.
*/
#include <linux/debugfs.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/soc/qcom/smem.h>
#include <linux/units.h>
#include "smem.h"
#define SMEM_DDR_INFO_ID 603
#define MAX_DDR_FREQ_NUM_V3 13
#define MAX_DDR_FREQ_NUM_V5 14
#define MAX_CHAN_NUM 8
#define MAX_RANK_NUM 2
#define DDR_HBB_MIN 13
#define DDR_HBB_MAX 19
#define MAX_SHUB_ENTRIES 8
static struct smem_dram *__dram;
enum ddr_info_version {
INFO_UNKNOWN,
INFO_V3,
INFO_V3_WITH_14_FREQS,
INFO_V4,
INFO_V5,
INFO_V5_WITH_6_REGIONS,
INFO_V6, /* INFO_V6 seems to only have shipped with 6 DDR regions, unlike V7 */
INFO_V7,
INFO_V7_WITH_6_REGIONS,
};
struct smem_dram {
unsigned long frequencies[MAX_DDR_FREQ_NUM_V5];
u32 num_frequencies;
u8 hbb;
};
enum ddr_type {
DDR_TYPE_NODDR = 0,
DDR_TYPE_LPDDR1 = 1,
DDR_TYPE_LPDDR2 = 2,
DDR_TYPE_PCDDR2 = 3,
DDR_TYPE_PCDDR3 = 4,
DDR_TYPE_LPDDR3 = 5,
DDR_TYPE_LPDDR4 = 6,
DDR_TYPE_LPDDR4X = 7,
DDR_TYPE_LPDDR5 = 8,
DDR_TYPE_LPDDR5X = 9,
};
/* The data structures below are NOT __packed on purpose! */
/* Structs used across multiple versions */
struct ddr_part_details {
__le16 revision_id1;
__le16 revision_id2;
__le16 width;
__le16 density;
};
struct ddr_freq_table {
__le32 freq_khz;
u8 enabled;
};
/* V3 */
struct ddr_freq_plan_v3 {
struct ddr_freq_table ddr_freq[MAX_DDR_FREQ_NUM_V3];
u8 num_ddr_freqs;
phys_addr_t clk_period_address;
};
struct ddr_details_v3 {
u8 manufacturer_id;
u8 device_type;
struct ddr_part_details ddr_params[MAX_CHAN_NUM];
struct ddr_freq_plan_v3 ddr_freq_tbl;
u8 num_channels;
};
/* Some V3 structs have an additional frequency level */
struct ddr_freq_plan_v3_14freqs {
struct ddr_freq_table ddr_freq[MAX_DDR_FREQ_NUM_V3 + 1];
u8 num_ddr_freqs;
phys_addr_t clk_period_address;
};
struct ddr_details_v3_14freqs {
u8 manufacturer_id;
u8 device_type;
struct ddr_part_details ddr_params[MAX_CHAN_NUM];
struct ddr_freq_plan_v3_14freqs ddr_freq_tbl;
u8 num_channels;
};
/* V4 */
struct ddr_details_v4 {
u8 manufacturer_id;
u8 device_type;
struct ddr_part_details ddr_params[MAX_CHAN_NUM];
struct ddr_freq_plan_v3 ddr_freq_tbl;
u8 num_channels;
u8 num_ranks[MAX_CHAN_NUM];
u8 highest_bank_addr_bit[MAX_CHAN_NUM][MAX_RANK_NUM];
};
/* V5 */
struct shub_freq_table {
u8 enable;
__le32 freq_khz;
};
struct shub_freq_plan_entry {
u8 num_shub_freqs;
struct shub_freq_table shub_freq[MAX_SHUB_ENTRIES];
};
struct ddr_xbl2quantum_smem_data {
phys_addr_t ssr_cookie_addr;
__le32 reserved[10];
};
struct ddr_freq_plan_v5 {
struct ddr_freq_table ddr_freq[MAX_DDR_FREQ_NUM_V5];
u8 num_ddr_freqs;
phys_addr_t clk_period_address;
__le32 max_nom_ddr_freq;
};
struct ddr_region_v5 {
__le64 start_address;
__le64 size;
__le64 mem_controller_address;
__le32 granule_size; /* MiB */
u8 ddr_rank;
#define DDR_RANK_0 BIT(0)
#define DDR_RANK_1 BIT(1)
u8 segments_start_index;
__le64 segments_start_offset;
};
struct ddr_regions_v5 {
__le32 ddr_region_num; /* We expect this to always be 4 or 6 */
__le64 ddr_rank0_size;
__le64 ddr_rank1_size;
__le64 ddr_cs0_start_addr;
__le64 ddr_cs1_start_addr;
__le32 highest_bank_addr_bit;
struct ddr_region_v5 ddr_region[] __counted_by_le(ddr_region_num);
};
struct ddr_details_v5 {
u8 manufacturer_id;
u8 device_type;
struct ddr_part_details ddr_params[MAX_CHAN_NUM];
struct ddr_freq_plan_v5 ddr_freq_tbl;
u8 num_channels;
u8 _padding;
struct ddr_regions_v5 ddr_regions;
};
/* V6 */
struct ddr_misc_info_v6 {
__le32 dsf_version;
__le32 reserved[10];
};
/* V7 */
struct ddr_details_v7 {
u8 manufacturer_id;
u8 device_type;
struct ddr_part_details ddr_params[MAX_CHAN_NUM];
struct ddr_freq_plan_v5 ddr_freq_tbl;
u8 num_channels;
u8 sct_config;
struct ddr_regions_v5 ddr_regions;
};
/**
* qcom_smem_dram_get_hbb(): Get the Highest bank address bit
*
* Context: Check qcom_smem_is_available() before calling this function.
* Because __dram * is initialized by smem_dram_parse(), which is in turn
* called from * qcom_smem_probe(), __dram will only be NULL if the data
* couldn't have been found/interpreted correctly.
*
* Return: highest bank bit on success, -ENODATA on failure.
*/
int qcom_smem_dram_get_hbb(void)
{
if (!__dram || !__dram->hbb)
return -ENODATA;
if (__dram->hbb < DDR_HBB_MIN || __dram->hbb > DDR_HBB_MAX)
return -ENODATA;
return __dram->hbb;
}
EXPORT_SYMBOL_GPL(qcom_smem_dram_get_hbb);
static void smem_dram_parse_v3_data(struct smem_dram *dram, void *data)
{
struct ddr_details_v3 *details = data;
for (int i = 0; i < MAX_DDR_FREQ_NUM_V3; i++) {
struct ddr_freq_table *freq_entry = &details->ddr_freq_tbl.ddr_freq[i];
if (freq_entry->freq_khz && freq_entry->enabled) {
u32 freq_khz = le32_to_cpu(freq_entry->freq_khz);
dram->frequencies[dram->num_frequencies++] = 1000 * freq_khz;
}
}
}
static void smem_dram_parse_v3_14freqs_data(struct smem_dram *dram, void *data)
{
struct ddr_details_v3_14freqs *details = data;
for (int i = 0; i < MAX_DDR_FREQ_NUM_V3 + 1; i++) {
struct ddr_freq_table *freq_entry = &details->ddr_freq_tbl.ddr_freq[i];
if (freq_entry->freq_khz && freq_entry->enabled)
dram->frequencies[dram->num_frequencies++] = 1000 * freq_entry->freq_khz;
}
}
static void smem_dram_parse_v4_data(struct smem_dram *dram, void *data)
{
struct ddr_details_v4 *details = data;
/* Rank 0 channel 0 entry holds the correct value */
dram->hbb = details->highest_bank_addr_bit[0][0];
for (int i = 0; i < MAX_DDR_FREQ_NUM_V3; i++) {
struct ddr_freq_table *freq_entry = &details->ddr_freq_tbl.ddr_freq[i];
if (freq_entry->freq_khz && freq_entry->enabled) {
u32 freq_khz = le32_to_cpu(freq_entry->freq_khz);
dram->frequencies[dram->num_frequencies++] = 1000 * freq_khz;
}
}
}
static void smem_dram_parse_v5_data(struct smem_dram *dram, void *data)
{
struct ddr_details_v5 *details = data;
struct ddr_regions_v5 *region = &details->ddr_regions;
dram->hbb = le32_to_cpu(region[0].highest_bank_addr_bit);
for (int i = 0; i < MAX_DDR_FREQ_NUM_V5; i++) {
struct ddr_freq_table *freq_entry = &details->ddr_freq_tbl.ddr_freq[i];
if (freq_entry->freq_khz && freq_entry->enabled) {
u32 freq_khz = le32_to_cpu(freq_entry->freq_khz);
dram->frequencies[dram->num_frequencies++] = 1000 * freq_khz;
}
}
}
static void smem_dram_parse_v7_data(struct smem_dram *dram, void *data)
{
struct ddr_details_v7 *details = data;
struct ddr_regions_v5 *region = &details->ddr_regions;
dram->hbb = le32_to_cpu(region[0].highest_bank_addr_bit);
for (int i = 0; i < MAX_DDR_FREQ_NUM_V5; i++) {
struct ddr_freq_table *freq_entry = &details->ddr_freq_tbl.ddr_freq[i];
if (freq_entry->freq_khz && freq_entry->enabled) {
u32 freq_khz = le32_to_cpu(freq_entry->freq_khz);
dram->frequencies[dram->num_frequencies++] = 1000 * freq_khz;
}
}
}
/* The structure contains no version field, so we have to perform some guesswork.. */
static int smem_dram_infer_struct_version(size_t size)
{
/* Some early versions provided less bytes of less useful data */
if (size < sizeof(struct ddr_details_v3))
return -EINVAL;
if (size == sizeof(struct ddr_details_v3))
return INFO_V3;
if (size == sizeof(struct ddr_details_v3_14freqs))
return INFO_V3_WITH_14_FREQS;
if (size == sizeof(struct ddr_details_v4))
return INFO_V4;
if (size == sizeof(struct ddr_details_v5) +
4 * sizeof(struct ddr_region_v5))
return INFO_V5;
if (size == sizeof(struct ddr_details_v5) +
4 * sizeof(struct ddr_region_v5) +
sizeof(struct ddr_xbl2quantum_smem_data) +
sizeof(struct shub_freq_plan_entry))
return INFO_V5;
if (size == sizeof(struct ddr_details_v5) +
6 * sizeof(struct ddr_region_v5))
return INFO_V5_WITH_6_REGIONS;
if (size == sizeof(struct ddr_details_v5) +
6 * sizeof(struct ddr_region_v5) +
sizeof(struct ddr_xbl2quantum_smem_data) +
sizeof(struct shub_freq_plan_entry))
return INFO_V5_WITH_6_REGIONS;
if (size == sizeof(struct ddr_details_v5) +
6 * sizeof(struct ddr_region_v5) +
sizeof(struct ddr_misc_info_v6) +
sizeof(struct shub_freq_plan_entry))
return INFO_V6;
if (size == sizeof(struct ddr_details_v7) +
4 * sizeof(struct ddr_region_v5) +
sizeof(struct ddr_misc_info_v6) +
sizeof(struct shub_freq_plan_entry))
return INFO_V7;
if (size == sizeof(struct ddr_details_v7) +
6 * sizeof(struct ddr_region_v5) +
sizeof(struct ddr_misc_info_v6) +
sizeof(struct shub_freq_plan_entry))
return INFO_V7_WITH_6_REGIONS;
return INFO_UNKNOWN;
}
static int smem_dram_frequencies_show(struct seq_file *s, void *unused)
{
struct smem_dram *dram = s->private;
for (int i = 0; i < dram->num_frequencies; i++)
seq_printf(s, "%lu\n", dram->frequencies[i]);
return 0;
}
DEFINE_SHOW_ATTRIBUTE(smem_dram_frequencies);
static int smem_hbb_show(struct seq_file *s, void *unused)
{
struct smem_dram *dram = s->private;
if (!dram->hbb)
return -EINVAL;
seq_printf(s, "%d\n", dram->hbb);
return 0;
}
DEFINE_SHOW_ATTRIBUTE(smem_hbb);
struct dentry *smem_dram_parse(struct qcom_smem *smem, struct device *dev)
{
struct dentry *debugfs_dir;
enum ddr_info_version ver;
struct smem_dram *dram;
size_t actual_size;
void *data;
/* No need to check qcom_smem_is_available(), this func is called by the SMEM driver */
data = __qcom_smem_get(smem, QCOM_SMEM_HOST_ANY, SMEM_DDR_INFO_ID, &actual_size);
if (IS_ERR_OR_NULL(data))
return ERR_PTR(-ENODATA);
ver = smem_dram_infer_struct_version(actual_size);
if (ver < 0) {
/* Some SoCs don't provide data that's useful for us */
return ERR_PTR(-ENODATA);
} else if (ver == INFO_UNKNOWN) {
/* In other cases, we may not have added support for a newer struct revision */
dev_err(dev, "Found an unknown type of DRAM info struct (size = %zu)\n",
actual_size);
return ERR_PTR(-EINVAL);
}
dram = devm_kzalloc(dev, sizeof(*dram), GFP_KERNEL);
if (!dram)
return ERR_PTR(-ENOMEM);
switch (ver) {
case INFO_V3:
smem_dram_parse_v3_data(dram, data);
break;
case INFO_V3_WITH_14_FREQS:
smem_dram_parse_v3_14freqs_data(dram, data);
break;
case INFO_V4:
smem_dram_parse_v4_data(dram, data);
break;
case INFO_V5:
case INFO_V5_WITH_6_REGIONS:
case INFO_V6:
smem_dram_parse_v5_data(dram, data);
break;
case INFO_V7:
case INFO_V7_WITH_6_REGIONS:
smem_dram_parse_v7_data(dram, data);
break;
default:
return ERR_PTR(-EINVAL);
}
debugfs_dir = debugfs_create_dir("qcom_smem", NULL);
debugfs_create_file("dram_frequencies", 0444, debugfs_dir, dram,
&smem_dram_frequencies_fops);
debugfs_create_file("hbb", 0444, debugfs_dir, dram, &smem_hbb_fops);
__dram = dram;
return debugfs_dir;
}