[PATCH v6 04/11] mtd: intel-dg: implement access functions

Alexander Usyskin
2025-03-02T14:21:02Z

Implement read(), erase() and write() functions.

CC: Lucas De Marchi <lucas.demarchi@intel.com>
CC: Rodrigo Vivi <rodrigo.vivi@intel.com>
Acked-by: Miquel Raynal <miquel.raynal@bootlin.com>
Co-developed-by: Tomas Winkler <tomasw@gmail.com>
Signed-off-by: Tomas Winkler <tomasw@gmail.com>
Co-developed-by: Vitaly Lubart <lubvital@gmail.com>
Signed-off-by: Vitaly Lubart <lubvital@gmail.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
---
drivers/mtd/devices/mtd_intel_dg.c | 197 +++++++++++++++++++++++++++++
1 file changed, 197 insertions(+)

diff --git a/drivers/mtd/devices/mtd_intel_dg.c b/drivers/mtd/devices/mtd_intel_dg.c
index ba1c720e717b..6f67cf966d05 100644
--- a/drivers/mtd/devices/mtd_intel_dg.c
+++ b/drivers/mtd/devices/mtd_intel_dg.c
@@ -5,13 +5,16 @@

#include <linux/bitfield.h>
#include <linux/bits.h>
+#include <linux/delay.h>
#include <linux/device.h>
#include <linux/intel_dg_nvm_aux.h>
#include <linux/io.h>
+#include <linux/io-64-nonatomic-lo-hi.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/string.h>
#include <linux/slab.h>
+#include <linux/sizes.h>
#include <linux/types.h>

struct intel_dg_nvm {
@@ -91,6 +94,33 @@ static inline u32 idg_nvm_read32(struct intel_dg_nvm *nvm, u32 address)
return ioread32(base + NVM_TRIGGER_REG);
}

+static inline u64 idg_nvm_read64(struct intel_dg_nvm *nvm, u32 address)
+{
+ void __iomem *base = nvm->base;
+
+ iowrite32(address, base + NVM_ADDRESS_REG);
+
+ return readq(base + NVM_TRIGGER_REG);
+}
+
+static void idg_nvm_write32(struct intel_dg_nvm *nvm, u32 address, u32 data)
+{
+ void __iomem *base = nvm->base;
+
+ iowrite32(address, base + NVM_ADDRESS_REG);
+
+ iowrite32(data, base + NVM_TRIGGER_REG);
+}
+
+static void idg_nvm_write64(struct intel_dg_nvm *nvm, u32 address, u64 data)
+{
+ void __iomem *base = nvm->base;
+
+ iowrite32(address, base + NVM_ADDRESS_REG);
+
+ writeq(data, base + NVM_TRIGGER_REG);
+}
+
static int idg_nvm_get_access_map(struct intel_dg_nvm *nvm, u32 *access_map)
{
u32 flmap1;
@@ -147,6 +177,173 @@ static int idg_nvm_is_valid(struct intel_dg_nvm *nvm)
return 0;
}

+__maybe_unused
+static unsigned int idg_nvm_get_region(const struct intel_dg_nvm *nvm, loff_t from)
+{
+ unsigned int i;
+
+ for (i = 0; i < nvm->nregions; i++) {
+ if ((nvm->regions[i].offset + nvm->regions[i].size - 1) > from &&
+ nvm->regions[i].offset <= from &&
+ nvm->regions[i].size != 0)
+ break;
+ }
+
+ return i;
+}
+
+static ssize_t idg_nvm_rewrite_partial(struct intel_dg_nvm *nvm, loff_t to,
+ loff_t offset, size_t len, const u32 *newdata)
+{
+ u32 data = idg_nvm_read32(nvm, to);
+
+ if (idg_nvm_error(nvm))
+ return -EIO;
+
+ memcpy((u8 *)&data + offset, newdata, len);
+
+ idg_nvm_write32(nvm, to, data);
+ if (idg_nvm_error(nvm))
+ return -EIO;
+
+ return len;
+}
+
+__maybe_unused
+static ssize_t idg_write(struct intel_dg_nvm *nvm, u8 region,
+ loff_t to, size_t len, const unsigned char *buf)
+{
+ size_t i;
+ size_t len8;
+ size_t len4;
+ size_t to4;
+ size_t to_shift;
+ size_t len_s = len;
+ ssize_t ret;
+
+ idg_nvm_set_region_id(nvm, region);
+
+ to4 = ALIGN_DOWN(to, sizeof(u32));
+ to_shift = min(sizeof(u32) - ((size_t)to - to4), len);
+ if (to - to4) {
+ ret = idg_nvm_rewrite_partial(nvm, to4, to - to4, to_shift, (uint32_t *)&buf[0]);
+ if (ret < 0)
+ return ret;
+
+ buf += to_shift;
+ to += to_shift;
+ len_s -= to_shift;
+ }
+
+ len8 = ALIGN_DOWN(len_s, sizeof(u64));
+ for (i = 0; i < len8; i += sizeof(u64)) {
+ u64 data;
+
+ memcpy(&data, &buf[i], sizeof(u64));
+ idg_nvm_write64(nvm, to + i, data);
+ if (idg_nvm_error(nvm))
+ return -EIO;
+ }
+
+ len4 = len_s - len8;
+ if (len4 >= sizeof(u32)) {
+ u32 data;
+
+ memcpy(&data, &buf[i], sizeof(u32));
+ idg_nvm_write32(nvm, to + i, data);
+ if (idg_nvm_error(nvm))
+ return -EIO;
+ i += sizeof(u32);
+ len4 -= sizeof(u32);
+ }
+
+ if (len4 > 0) {
+ ret = idg_nvm_rewrite_partial(nvm, to + i, 0, len4, (uint32_t *)&buf[i]);
+ if (ret < 0)
+ return ret;
+ }
+
+ return len;
+}
+
+__maybe_unused
+static ssize_t idg_read(struct intel_dg_nvm *nvm, u8 region,
+ loff_t from, size_t len, unsigned char *buf)
+{
+ size_t i;
+ size_t len8;
+ size_t len4;
+ size_t from4;
+ size_t from_shift;
+ size_t len_s = len;
+
+ idg_nvm_set_region_id(nvm, region);
+
+ from4 = ALIGN_DOWN(from, sizeof(u32));
+ from_shift = min(sizeof(u32) - ((size_t)from - from4), len);
+
+ if (from - from4) {
+ u32 data = idg_nvm_read32(nvm, from4);
+
+ if (idg_nvm_error(nvm))
+ return -EIO;
+ memcpy(&buf[0], (u8 *)&data + (from - from4), from_shift);
+ len_s -= from_shift;
+ buf += from_shift;
+ from += from_shift;
+ }
+
+ len8 = ALIGN_DOWN(len_s, sizeof(u64));
+ for (i = 0; i < len8; i += sizeof(u64)) {
+ u64 data = idg_nvm_read64(nvm, from + i);
+
+ if (idg_nvm_error(nvm))
+ return -EIO;
+
+ memcpy(&buf[i], &data, sizeof(data));
+ }
+
+ len4 = len_s - len8;
+ if (len4 >= sizeof(u32)) {
+ u32 data = idg_nvm_read32(nvm, from + i);
+
+ if (idg_nvm_error(nvm))
+ return -EIO;
+ memcpy(&buf[i], &data, sizeof(data));
+ i += sizeof(u32);
+ len4 -= sizeof(u32);
+ }
+
+ if (len4 > 0) {
+ u32 data = idg_nvm_read32(nvm, from + i);
+
+ if (idg_nvm_error(nvm))
+ return -EIO;
+ memcpy(&buf[i], &data, len4);
+ }
+
+ return len;
+}
+
+__maybe_unused
+static ssize_t
+idg_erase(struct intel_dg_nvm *nvm, u8 region, loff_t from, u64 len, u64 *fail_addr)
+{
+ u64 i;
+ const u32 block = 0x10;
+ void __iomem *base = nvm->base;
+
+ for (i = 0; i < len; i += SZ_4K) {
+ iowrite32(from + i, base + NVM_ADDRESS_REG);
+ iowrite32(region << 24 | block, base + NVM_ERASE_REG);
+ /* Since the writes are via sguint
+ * we cannot do back to back erases.
+ */
+ msleep(50);
+ }
+ return len;
+}
+
static int intel_dg_nvm_init(struct intel_dg_nvm *nvm, struct device *device)
{
int ret;
--
2.43.0